cyproconazole (ISO); (2RS,3RS;2RS,3SR)-2-(4-chlorophenyl)-3-cyclopropyl-1-(1H-1,2,4-triazol-1-yl)butan-2-ol

Toxicity to terrestrial plants

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

toxicity to terrestrial plants: long-term

Type of information:

experimental study

Adequacy of study:

key study

Study period:

23 May 1996 - 28 May 1997

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EPA OPP 122-1 (Terrestrial Plant Toxicity Tier I (seedling emergence))

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPP 123-1 (Seedling Emergence Tier II)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

On both application days, samples for the analytical confirmation of test concentrations were collected by pouring from each spray mixture. Triplicate samples of the 18 and 280 g a.i./A spray mixtures were collected to determine the homogeneity of the spray mixtures, one sample was collected from each of the other spray mixtures. Chemical analysis by gas chromatography of the spray mixture samples, as well as matrix blanks and fortifications, was performed by the test facility according to methodology supplied by the Sponsor.

Vehicle:

no

Details on preparation and application of test substrate:

- Preparation of Spray Mixtures: Spray mixtures for each of the five test concentrations (18, 35, 70, 140, and 280 g a.i./acre test substance, nominal) were prepared from the test substance on July 9, 1996 and October 7, 1996. On each day, a 3700 ppm a.i. (nominal) solution of the test substance was prepared by diluting the test substance in well water purified by reverse osmosis, followed with mixing by inversion. The 3700 ppm a.i. solution served as the spray mixture for the 280 g a.i./ acre application rate treatment group. Spray mixtures for the remaining treatment groups were prepared by diluting aliquots of the 3700 ppm a.i. solution with well water purified by reverse osmosis.

- Application of Spray Mixtures: A pressurised spray applicator was used to spray the soil surface in pots in order to simulate inadvertent direct application or the occurrence of off-target drift resulting from the use of actual field application equipment. The applicator consisted of a pressurised 80 mL polyethylene spray bottle that contained the spray mixture and a boom with 2 spray nozzles. These parts were connected by various hoses and connectors, and were all mounted on a moveable frame. An external source of compressed carbon dioxide was attached to the applicator and set at 20 psi to force the contents of the spray bottle through the hoses and ultimately out of the applicator via the spray nozzles. A system of valves was used to control the pressurisation of the spray bottle and the movement of fluids through the applicator. The applicator was designed to deliver the entire contents of the spray bottle during an application.
Pots containing soil and seeds were placed in a galvanised water tank that served as a protected area for spraying. The vertical walls of the tank reduced interference from air currents, contained the spray within a small area, and supported the frame of the applicator. The applicator was placed across the open top of the water tank with the boom and nozzles suspended over the bottom of the tank. The spray nozzles were suspended approximately 30 cm above the growth pots during delivery of the spray mixture. The tank was lined with an absorbent material (cat litter) to help contain over-spray.
The test substance application in this study was designed to represent four concurrent applications of the test substance at the maximum label rate. Since the label rate indicates an aerial field spray volume of 5 gallons per acre, spray mixtures for this study were applied at a volume of 20 gallons/acre. The target spray mixtures for the five treatment groups corresponded to application rates of 18, 35, 70, 140, and 280 g a.i./acre of the test substance, respectively. The maximum proposed application rate for the test substance is 70 g a.i./acre, with a maximum of four applications per year. Applications were made to the control first, followed by applications of spray mixtures from lowest to highest concentration. Applications were made on July 9, 1996, and October 7, 1996.

Species:

Phaseolus vulgaris

Plant group:

Dicotyledonae (dicots)

Details on test organisms:

- Common name: Bean
- Family: Fabaceae

Species:

Brassica oleracea var. capitata

Plant group:

Dicotyledonae (dicots)

Details on test organisms:

- Common name: Cabbage
- Family: Cruciferae

Species:

Daucus carota

Plant group:

Dicotyledonae (dicots)

Details on test organisms:

- Common name: Carrot
- Family: Umbelliferae

Species:

Zea mays

Plant group:

Monocotyledonae (monocots)

Details on test organisms:

- Common name: Corn
- Family: Gramineae

Species:

Lactuca sativa

Plant group:

Dicotyledonae (dicots)

Details on test organisms:

- Common name: Lettuce
- Family: Compositae

Species:

Allium cepa

Plant group:

Monocotyledonae (monocots)

Details on test organisms:

- Common name: Onion
- Family: Amaryllidaceae

Species:

Lolium perenne

Plant group:

Monocotyledonae (monocots)

Details on test organisms:

- Common name: Rye Grass
- Family: Gramineae

Species:

Glycine max (G. soja)

Plant group:

Dicotyledonae (dicots)

Details on test organisms:

- Common name: Soybean
- Family: Leguminosae

Species:

Lycopersicon esculentum

Plant group:

Dicotyledonae (dicots)

Details on test organisms:

- Common name: Tomato
- Family: Solanaceae

Species:

Triticum aestivum

Plant group:

Monocotyledonae (monocots)

Details on test organisms:

- Common name: Wheat
- Family: Poaceae

Test type:

seedling emergence toxicity test

Study type:

laboratory study

Substrate type:

artificial soil

Limit test:

no

Total exposure duration:

14 d

Test temperature:

19.4 - 27.8 °C

pH:

7.7

Moisture:

44% - 96% (Relative Humidity)

Details on test conditions:

TEST SYSTEM
- Test container: Growth pot
- No. of seeds per container: 10
- No. of replicates per treatment group: 4
- No. of replicates per control: 4
- Planting of Seeds; Seeds were planted in plastic pots (approximately 16 cm in diameter and 12 cm deep) on the day of test substance application. A template was used to gently compact the soil and leave ten uniform holes for planting. One indiscriminately selected seed was then planted in each hole, for a total of ten seeds in each pot. Holes were then closed by slightly depressing the soil surface.

SOURCE AND PROPERTIES OF SUBSTRATE (if soil)
- % sand: 90%
- % silt: 5%
- % clay: 5%
- pH: 7.7
- Soil taxonomic classification: Sandy loam (sand, clay, and peat mixed in a 50:4:5 ratio (w:w:w))
- Organic matter (%): 1.41%
- Pesticide and Metal Screening of Well Water and Soil: The well water and soil used for plant studies were periodically screened for pesticide and metals. No analytes were measured at levels that were expected to have an impact on the study.

GROWTH CONDITIONS
- Watering of Seedlings: Water lost through transpiration and evaporation was replaced by sub-irrigation with well water from the greenhouse facility. Seedlings were sub-irrigated to minimize the potential for the leaching of the test substance through the soil. Sub-irrigation trays were filled to a predetermined depth to help standardize the amount of water delivered to each tray.

EFFECT PARAMETERS MEASURED
Observations on Day 10 were made to document seedling emergence. Observations on Day 14 were made to document seedling emergence and growth, and to determine changes in the general condition of seedlings following the application of the test substance. Observations consisted of noting whether emergence had or had not occurred and assessing the condition of each seedling. Emergence was defined as the presence of visible plant tissue at the surface of the soil. Seedling condition was described by noting the presence or absence of possible signs of phytotoxicity such as colour changes, necrosis, leaf curling, chlorosis, plant lodging or plant stunting. Each emerged seedling was then assigned a numerical score that described the plant condition.
The growth of emerged seedlings was evaluated by assessing the height, fresh weight, and dry weight of living seedlings at test termination. Seedling height was measured with a ruler to the nearest whole centimetre from the surface of the soil to either the apical meristem (bean, soybean, and tomato) or the tip of the tallest leaf of the seedling (all other species). Seedling fresh weight was measured at test termination by clipping the seedling stem at soil level and weighing the above-ground (shoot) portion of all living seedlings within a replicate as a group. The resulting weight was divided by the number of seedlings included in the measurement in order to determine the mean shoot fresh weight. Shoots then were placed in a drying oven and dried to a constant weight at approximately 70°C. When dry, the shoots were re-weighed, and the mean shoot dry weight was determined.

Nominal and measured concentrations:

Spray mixtures prepared on July 9, 1996 (applied to the Tier I tests for bean, carrot, corn, lettuce, soybean, and wheat, and Tier II tests for cabbage, rye grass, and tomato)
- Nominal concentration: 0, 18, 35, 70, 140, and 280 g a.i./acre (coressponding to 0, 231, 463, 925, 1850 and 3700 mg a.i./L, respectively)
- Measured concentration: 0 (negative control), 17, 30, 68, 98, and 290 g a.i./ acre

Spray mixtures prepared on October 7, 1996 (applied to the Tier I test for onion and Tier II test for lettuce)
- Nominal concentration: 0, 18, 35, 70, 140, and 280 g a.i./acre (coressponding to 0, 231, 463, 925, 1850 and 3700 mg a.i./L, respectively)
- Measured concentration: 0 (negative concentration), 16, 32, 66, 140, and 260 g a.i./ acre.

Reference substance (positive control):

no

Key result

Species:

Brassica oleracea var. capitata

Duration:

14 d

Dose descriptor:

NOEC

Effect conc.:

0.115 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

other: Emergence, Survival and Growth

Remarks on result:

other: Originally reported as 35 g a.i./acre

Key result

Species:

other: Lactuca sativa and Lycopersicon esculentum

Duration:

14 d

Dose descriptor:

NOEC

Effect conc.:

0.115 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

other: Condition

Remarks on result:

other: Originally reported as 35 g a.i./acre

Key result

Species:

other: Brassica oleracea var. capitata, Lactuca sativa and Lycopersicon esculentum

Duration:

14 d

Dose descriptor:

EC50

Effect conc.:

> 0.92 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

other: Emergence Survival and Growth

Remarks on result:

other: Originally reported as > 280 g a.i./acre.

Species:

other: Phaseolus vulgaris, Daucus carota, Zea mays, Allium cepa, Lolium perenne, Glycine max and Triticum aestivum

Duration:

14 d

Dose descriptor:

NOEC

Effect conc.:

0.92 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

other: Emergence, Survival and Growth

Remarks on result:

other: Originally reported as 280 g a.i./acre

Details on results:

An overview of the results is provided in Table 3 – Table 10 in ‘Any other information on results incl. tables’.

TIER I TESTS
There were no apparent treatment related effects upon bean, carrot, corn, onion, soybean, or wheat seedlings in the 280 g a.i./ A treatment group. Any differences from the controls were slight and were not statistically significant. The NOEC for emergence and growth of beans, carrots, corn, onions, soybeans, and wheat seedlings in this study was determined to be the nominal application rate of 280 g a.i./acre, the highest concentration tested. There did appear to be treatment related effects upon emergence, fresh weight, dry weight, and height of lettuce seedlings in the 280 g a.i./ acre treatment group. Several lettuce seedlings also were observed to be slightly necrotic at test termination. While only the effect upon mean height was significantly different (p < 0.05) from the control mean, the reduction in growth and the presence of necrosis among lettuce seedlings were considered to be treatment related. Therefore, lettuce was retested using Tier II procedures.

TIER II TESTS
- Cabbage: There were no apparent treatment related effects upon cabbage condition, growth, or emergence in the 18 and 35 g a.i./acre treatment groups. However, there were treatment related decreases in emergence and growth (weight and height measurements) among cabbage seedlings in the 70, 140, and 280 g a.i./acre treatment groups. Mean emergence relative to the control mean at test termination was reduced in the 70, 140, and 280 g a.i./acre groups, although only the 140 g a.i./acre group mean was significantly different from the control mean (p < 0.05). There also appeared to be slight delays in the timing of seedling emergence in the 140 and 280 g a.i./acre treatment groups compared with the control. The number of seedlings emerging between Days 10 and 14 in the control and in the 18, 35, 70, 140, and 280 g a.i./acre treatment groups were 0, 1, 0, 2, 4, and 4, respectively. Reductions in mean fresh and dry weight and height resulted in significant differences from the control in all three of the highest treatment groups. Although occasional incidental observations of plant mortality and stem curl were noted among cabbage seedlings in various treatment groups, such findings were not concentration dependent and not considered to be treatment related. However, treatment related effects upon the condition of cabbage seedlings were noted in the 70, 140, and 280 g a.i./acre treatment groups. There were 2, 2, and 3 seedlings in the 70, 140, and 280 g a.i./acre treatment groups, respectively, that were slightly necrotic on Day 14, although the necrosis was generally restricted to the cotyledons, and did not appear life-threatening. Since both the number of affected individuals and the severity of the necrosis were concentration dependent, the necrosis was considered to be treatment related. Based on the observed effects upon seedling condition (necrosis), growth, and emergence, the LOEC and the NOEC for cabbage were determined to be the nominal application rates of 70 and 35 g a.i./acre, respectively. There was insufficient response in these variables to calculate meaningful EC50 values.
 
- Lettuce: There were no apparent treatment related effects upon the emergence, growth (weight and height), and condition of lettuce seedlings in the 18 and 35 g a.i./acre treatment groups. Although occasional incidental necrosis, chlorosis, and mortality were observed in both groups, such observations were few in number and not considered to be treatment related. One seedling in the 280 g a.i./acre group was slightly chlorotic at test termination, but the chlorosis was not considered treatment related. There did appear to be treatment related effects upon plant condition in the 70, 140, and 280 g a.i./acre treatment groups, where slight leaf curl was observed in 1, 11, and 30 seedlings, respectively. While the frequency of leaf curl increased with concentration, there were no apparent increases in the severity of the condition. In addition, two and three seedlings in the 140 g a.i./acre and 280 g a.i./acre treatment groups, respectively, emerged but died prior to test termination. The specific causes of the seedling deaths were not determined. However, since the mortalities were restricted to the two highest test concentrations, they were considered to be treatment related.
No apparent treatment related effects upon emergence or weight were observed at any tested concentration, however, mean height in the 280 g a.i./acre treatment group was 76% of the control group mean. The height reduction was only observed in the nominal 280 g a.i./acre treatment group, appeared to be treatment related, and was statistically significant (p < 0.01). Based on the presence of leaf curl, the LOEC and NOEC for lettuce were determined to be the nominal application rates of 70 and 35 g a.i./A, respectively. There was insufficient response in these variables to calculate meaningful EC25 or EC50 values.

- Rye Grass: There were no apparent treatment related effects upon emergence, growth (weight and height measurements), or condition of rye grass seedlings in any of the treatment groups. Although incidental observations of lodging or leaf curl were noted in two plants, the observations were not concentration dependent or treatment related. Therefore, the NOEC for rye grass was determined to be the nominal application rate of 280 g a.i./acre, the highest concentration tested. There was insufficient response in these variables to calculate meaningful EC10, EC25, or EC50 values.

- Tomato: The results show no apparent treatment related effects upon the emergence, growth (weight and height), and condition of tomato seedlings in the 18 and 35 g a.i./acre treatment groups. Although occasional incidental observations of tomato seedlings not shedding their seed coats were noted, such observations were few in number and also were noted in the control group.
There did appear to be treatment related effects upon plant condition in the 70, 140, and 280 g a.i./acre treatment groups. Stem curl was observed in 2, 3, and 4 seedlings while leaf curl was noted in 1, 1, and 5 seedlings on the 70, 140, and 280 g a.i./acre treatment groups, respectively. While the frequency of stem and leaf curl increased with concentration, there were no apparent increases in the severity of the condition. In addition, 4, 2, and 3 seedlings in the 70, 140, and 280 g a.i./acre treatment groups, respectively, emerged but died prior to test termination. The specific causes of the seedling deaths were not determined. However, since the mortalities were restricted to the three highest test concentrations, they were considered to be treatment related. Incidental chlorosis was observed in the 140 g a.i./acre group but was not considered treatment related. Although there were no effects upon emergence and growth in the 280 g a.i./acre treatment group, there were incidental reductions relative to the control in both emergence and seedling height (significant, p < 0.05) in the 140 g a.i./acre treatment group, where treatment group means were 82 and 76% of control means, respectively. The reductions were not concentration dependent and were not considered to be treatment related. Based on the presence of stem and leaf curl, the LOEC and NOEC for tomato were determined to be the nominal application rates of 70 and 35 g a.i./acre, respectively. There was insufficient response in these variables to calculate meaningful EC10, EC25, or EC50 values.

Reported statistics and error estimates:

See Data Analyses in 'Any other information on materials and methods incl. tables'.

Table 3 Summary of Tier I seedling emergence

Species	Treatment Group	Mean ± SD	Mean ± SD	% Emergence	95%CL Lower	95%CL Upper	% Inhibition
Bean	Control	9.5 ± 0.58	9.5 ± 0.58	95	8.58	10.42	-3
	Treatment	9.8 ± 0.50	9.8 ± 0.50	98	8.95	10.55
Carrot	Control	6.8 ± 2.06	7.3 ± 1.50	73	4.86	9.64	0
	Treatment	7.3 ± 0.50	7.3 ± 0.50	73	6.45	8.05
Corn	Control	10.0 ± 0.00	10.0 ± 0.00	100	10.00	10.00	2
	Treatment	9.8 ± 0.50	9.8 ± 0.50	98	8.95	10.55
Lettuce1	Control	6.3 ± 2.75	8.0 ± 1.83	80	5.10	10.90	19
	Treatment	5.3 ± 2.87	6.5 ± 2.52	65	2.50	10.50
Onion1	Control	5.0 ± 1.41	7.0 ± 1.15	70	4.54	9.46	-4
	Treatment	4.8 ± 1.71	7.3 ± 1.26	73	5.25	9.25
Soybean	Control	10.0 ± 0.00	10.0 ± 0.00	100	10.00	10.00	0
	Treatment	10.0 ± 0.00	10.0 ± 0.00	100	10.00	10.00
Wheat	Control	9.5 ± 0.58	9.5 ± 0.58	95	8.58	10.42	-3
	Treatment	9.8 ± 0.50	9.8 ± 0.50	98	8.95	10.55

1. Test termination for lettuce was on Day 17, and for onion was on Day 21, rather than Day 14.

Table 4. Summary of Tier I Dry and Fresh Shoot Weight of Seedlings Collected at Test Termination 

		Dry weight (mg)			Fresh weight (mg)
Species	Treatment Group	Mean ± SD	% of Control	% Inhibition	Mean ± SD	% of Control	% Inhibition
Bean	Control Treatment	542 ± 43.l 530 ± 92.1	98	2	4586 ± 355.7 4433 ± 511.1	97	3
Carrot	Control Treatment	1.8 ± 0.23 2.2 ± 0.46	119	-19	14 ± 1.4 16 ± 3.4	108	-8
Corn	Control Treatment	271 ± 18.5 293 ± 11.4	108	-8	3492 ± 245.9 3786 ± 179.4	108	-8
Lettuce	Control Treatment	14.4 ± 5.26 8.6 ± 3.64	60	40	277 ± 103.5 151 ± 68.3	55	45
Onion	Control Treatment	4.8 ±0.53 4.3 ±0.91	90	I0	56 ± 7.0 52 ± 7.5	93	7
Soybean	Control Treatment	247 ± 12.2 234 ± I0.1	95	5	2104 ± 117.4 2041 ± 58.9	97	3
Wheat	Control Treatment	49.0 ± 6.68 54.6 ± 6.00	111	-11	454 ± 61.4 507 ± 53.8	112	-12

  Table 5. Summary of Tier I Seedling Height (cm) at Test Termination

Species	Treatment Group	Mean ± SD	% of Control	% Inhibition
Bean	Control	12 .5 ± 0.66	91	9
	Treatment	11.3 ± 1.61
Carrot	Control	3.5 ± 0.24	88	12
	Treatment	3.1 ± 0.49
Corn	Control	42.7 ± 1.63	103	-3
	Treatment	44.1 ± 1.90
Lettuce	Control	4.3 ± 0.77	65	35
	Treatment	2.8 ± 0.82*
Onion	Control	5.7 ± 0.62	100	0
	Treatment	5.7 ± 0.49
Soybean	Control	15.1 ± 0.67	95	5
	Treatment	14.3 ± 0.93
Wheat	Control	24.5 ± 1.43	109	-9
	Treatment	26.7 ± 0.80

* Treatment group mean is significantly different from the control group mean (2-tailed t-test,  α = 0.05).

Table 6. Observed NOEC¹and Calculated EC10, EC25, and EC50

 

 

Species	Parameters	NOEC (mg a.i./acre)	Calculated ECx Estimates^2
			EC10 (95%CL)	EC25  (95%CL)	EC50 (95%CL)
Cabbage	Condition^3	35	-	-	-
	Emergence	35	30.8 (23. 1 - 47.1)	56.7 (ND^4)	> 280
	Height	35	40 (31.2 - 49.8)	60.1 (48.9 - 76.9)	> 280
	Fresh Weight	35	39.8 (33.4 - 45.6)	54.4 (47.1 - 69.1)	97.6 (ND)
	Dry Weight	35	40.5 (32.8 - 46.0)	56.0 (47.2 - 70.7)	> 280
Lettuce	Condition	35	-	-	-
	Emergence	280	> 280	> 280	> 280
	Height	140	144 (49.0 - 180)	256 (ND)	> 280
	Fresh Weight	280	200 (ND)	> 280	> 280
	Dry Weight	280	> 280	> 280	> 280
Rye Grass	Condition	280	-	-	-
	Emergence	280	> 280	> 280	> 280
	Height	280	29.5 (nd)	> 280	> 280
	Fresh Weight	280	75.0 (ND)	> 280	> 280
	Dry Weight	280	90.9 (ND)	> 280	> 280
Tomato	Condition	35	-	-	-
	Emergence	280	90.6 (ND)	> 280	> 280
	Height	280	17.5 (ND)	> 280	> 280
	Fresh Weight	280	16.0 (ND)	> 280	> 280
	Dry Weight	280	187 (ND)	> 280	> 280

1. The NOEC is defined as the highest test concentration with no observable treatment related effects, and therefore may not take on values between test concentrations. Calculated ECx estimates are not always consistent with NOEC determinations. For example, a calculated 10% difference (EC10) may not be meaningful or observable due to variability in the data. Additionally, NOEC determinations may be based upon qualitative assessments of plant condition which are not included in the ECx calculations.

2. Estimates calculated by ICPIN using measured test concentrations. All EC90 estimates were > 280 g a.i./ACRE.

3. Since plant condition is a qualitative assessment, only the NOEC was determined and reported.

4. The method used by ICPIN could not determine 95% confidence limits.

Table 7. Summary of Tier II test results (cabbage)

	Emergence on Day 14			Dry Weight (mg)   on Day 14			Fresh Weight (mg)   on Day 14			Seedling Height on Day 14
Application rate^1 (g a.i./acre)	Mean ± SD	95% CL Lower	95% CL Upper	Mean ± SD (% of control)	95% CL Lower	95% CL Upper	Mean ± SD (% of control)	95% CL Lower	95% CL Upper	Mean ± SD (% of control)	95% CL Lower	95% CL Upper
0 (Control)	8.5 ± 1.00	6.91	10.09	32.4± 2.45	28.5	36.3	470 ± 29.8	423	518	6.2 ± 0.43	5.5	6.9
17	9.8±0.50 (115%)	8.95	10.55	31.2 ± 3.56 (96%)	25.6	36.9	453 ± 50.9 (96%)	372	534	5.7 ± 0.70 (93%)	4.6	6.9
30	8.3 ± 1.26 (97%)	6.25	10.25	31.2 ± 3.56 (104%)	29.4	37.7	495 ± 39.8 (105%)	432	559	6.3 ± 0.45 (102%)	5.6	7.0
68	6.0 ± 1.83 (71%)	3.10	8.90	20.6 ± 6.11 * (64%)	10.9	30.3	289 ± 89.3** (61%)	147	431	4.3 ± 1.01** (69%)	2.7	5.9
98	5.8 ± 0.50* (68%)	4.95	6.55	14.9 ± 5.99** (46%)	5.4	24.4	207 ± 82.0** (44%)	76	337	3.1 ± 0.79** (51%)	1.9	4.4
290	7.0 ± 2.16 (82%)	3.56	10.44	18.9 ± 5.95** (58%)	9.4	28.3	265 ± 92.7** (56%)	117	412	3.5 ± 0.97** (56%)	2.0	5.0

1. Application rates based on measured concentrations of the test substance in spray mixtures.

* Treatment group mean is significantly different from the control group mean (Dunnett's 2-tailed test,α=0.05).

** Treatment group mean is significantly different from the control group mean (Dunnett's 2-tailed test,α=0.01).

Table 8. Summary of Tier II test results (Lettuce)

	Emergence on Day 14			Dry Weight (mg)   on Day 14			Fresh Weight (mg)   on Day 14			Seedling Height on Day 14
Application rate^1 (g a.i./acre)	Mean ± SD	95% CL Lower	95% CL Upper	Mean ± SD (% of control)	95% CL Lower	95% CL Upper	Mean ± SD (% of control)	95% CL Lower	95% CL Upper	Mean ± SD (% of control)	95% CL Lower	95% CL Upper
0 (Control)	10.0 ± 0.00	10.00	10.00	4.6±0.47	3.8	5.3	68 ± 7.9	56	81	2.7 ± 0.11	2.5	2.9
17	9.8 ± 0.50 (98%)	8.95	10.55	4.3 ± 0.55 (94%)	3.4	5.2	68 ± 9.7  (99%)	52	83	2.8 ± 0.24 (104%)	2.4	3.2
30	9.8 ± 0.50 (98%)	8.95	10.55	5.0±0.57 (110%)	4.1	5.9	72 ± 7.1 (106%)	61	83	2.7 ± 0.22 (102%)	2.4	3.1
68	9.3 ± 0.96 (73%)	7.73	10.77	5.1 ±0.54 (111%)	4.2	5.9	76 ± 13.0 (111%)	55	96	2.5 ± 0.27 (94%)	2.1	3.0
98	9.8 ± 0.50 (98%)	8.70	11.30	4.4 ± 0.76 (95%)	3.2	5.6	64 ± 10.0 (94%)	48	80	2.5 ± 0.23 (92%)	2.1	2.9
290	10.0 ± 0.00 (100%)	10.00	10.00	4.3 ±0.54 (95%)	3.5	5.2	64 ± 7.2 (93%)	52	75	2.0 ± 0.16** (76%)	1.8	2.3

1. Application rates based on measured concentrations of the test substance in spray mixtures.

* Treatment group mean is significantly different from the control group mean (Dunnett's 2-tailed test,α=0.05).

** Treatment group mean is significantly different from the control group mean (Dunnett's 2-tailed test,α=0.01).

Table 9. Summary of Tier II test results (Rye grass)

	Emergence on Day 14			Dry Weight (mg)  on Day 14			Fresh Weight (mg)   on Day 14			Seedling Height on Day 14
Application rate^1 (g a.i./acre)	Mean ± SD	95% CL Lower	95% CL Upper	Mean ± SD (% of control)	95% CL Lower	95% CL Upper	Mean ± SD (% of control)	95% CL Lower	95% CL Upper	Mean ± SD (% of control)	95% CL Lower	95% CL Upper
0 (Control)	8.8 ± 0.96	7.23	10.27	3.9 ± 0.47	3.1	4.6	38 ± 3.8	32	44	9.4 ± 0.65	8.4	10.4
17	9.0 ± 0.00 (103%)	9.00	9.00	4.6 ± 0.98 (118%)	3.0	6.1	44 ± 7.1 (117%)	33	56	10.3 ± 1.18 (109%)	8.4	12.1
30	9.0 ± 0.82 (103%)	7.70	10.30	3.9 ± 1.29 (100%)	1.8	5.9	36 ± 12.9 (94%)	15	56	8.4 ± 1.52 (90%)	6.0	10.9
68	9.0 ± 0.82 (103%)	7.70	10.30	4.5 ± 1.26 (115%)	2.4	6.4	41 ± 10.8 (107%)	23	58	9.1±1.32 (97%)	7.1	11.2
98	8.8 ± 0.96 (100%)	7.23	10.27	3.3 ± 0.39 (86%)	2.7	4.0	30 ± 3.6 (80%)	25	36	7.9 ± 0.51 (84%)	7.1	8.7
290	8.3 ± 1.71 (95%)	5.53	10.97	4.1 ± 0.13 (105%)	3.9	4.3	37 ± 1.5 (97%)	34	39	8.5 ± 0.69 (91%)	7.4	9.6

1. Application rates based on measured concentrations of the test substance in spray mixtures.

* Treatment group mean is significantly different from the control group mean (Dunnett's 2-tailed test,α=0.05).

** Treatment group mean is significantly different from the control group mean (Dunnett's 2-tailed test,α=0.01).

Table 10. Summary of Tier II test results (tomato) 

	Emergence on Day 14			Dry Weight (mg)   on Day 14			Fresh Weight (mg)   on Day 14			Seedling Height on Day 14
Application rate^1 (g a.i./acre)	Mean ± SD	95% CL Lower	95% CL Upper	Mean ± SD (% of control)	95% CL Lower	95% CL Upper	Mean ± SD (% of control)	95% CL Lower	95% CL Upper	Mean ± SD (% of control)	95% CL Lower	95% CL Upper
0 (Control)	9.5 ± 0.58	8.58	10.42	8.5 ± 1.11	6.7	10	117 ± 14.5	94	140	3.7 ± 0.41	3.00	4.31
17	9.0 ± 1.15 (95%)	7.16	10.84	7.2 ± 1.94 (85%)	4.1	10	98 ± 24.3 (83%)	59	136	3.3 ± 0.35 (90%)	2.74	3.87
30	9.0 ± 0.00 (95%)	9.00	9.00	7.0 ± 2.06 (83%)	3.7	10	95 ± 29.1 (81%)	49	141	3.0 ± 0.54 (83%)	2.17	3.90
68	9.3 ± 0.96 (97%)	7.73	10.77	8.9 ± 1.84 (105%)	6.0	12	120 ± 23.3 (102%)	83	157	3.1 ± 0.47 (84%)	2.32	3.81
98	7.8 ± 1.50 (82%)	5.36	10.14	7.3 ± 0.60 (86%)	6.4	8.3	100 ± 6.8 (85%)	89	111	2.8 ± 0.32* (76%)	2.27	3.29
290	9.0 ± 0.00 (95%)	9.00	9.00	8.9 ± 2.58 (105%)	4.8	13	114 ± 37.6 (97%)	54	174	3.0 ± 0.51 (81%)	2.15	3.77

1. Application rates based on measured concentrations of the test substance in spray mixtures.

* Treatment group mean is significantly different from the control group mean (Dunnett's 2-tailed test,α=0.05).

** Treatment group mean is significantly different from the control group mean (Dunnett's 2-tailed test,α=0.01).

 

 

Validity criteria fulfilled:

yes

Conclusions:

Based on these findings, the NOEC for bean, carrot, corn, onion, rye grass, soybean, and wheat seedlings was determined to be 0.92 mg/kg soil dw (equivalent to 280 g a.i./acre or 0.69 kg a.i./ha), or approximately four times the maximum single application rate.The NOEC for cabbage, lettuce, and tomato was determined to be the nominal application rate of 0.115 mg/kg soil dw (equivalent to 35 g a.i./acre or 0.086 kg a.i./ha).

Executive summary:

The effects of the test substance (320 SC) on the survival, emergence and growth of ten plants species was studied by following FIFRA 122-1 and 123-1 guidelines. The study was compliance with GLP criteria. In total, ten plant species (four monocotyledonae and six dicotyledonae plant species) were included in this study. Seven plant species (bean, carrot, corn, lettuce, onion, soybean, and wheat), were tested at Tier I (FIFRA Subdivision J, Series 122-1), which consisted of a single test substance concentration (280g a.i./acre equivalent to 0.92 mg/kg soil dw) and a negative control. Four species (cabbage, lettuce, rye grass, and tomato) were tested at Tier II (FIFRA Subdivision J, Series 123-1), which consisted of a series of five nominal test concentrations (18, 35, 70, 140, and 280 g a.i./acre equivalent to 0.059, 0.115, 0.231, 0.461 and 0.923 mg/kg soil dw) and a negative control group. For each species tested, one application of each of the various treatments was made by spraying the soil with the appropriate concentration of aqueous spray mixtures of the test substance. During the test, phytotoxic effects of the test substance on seedling emergence and growth of emerged seedlings were evaluated. The test duration was extended for onions and lettuce to allow for adequate time for germination and emergence. 

The results showed that the test substance had no apparent treatment related effects upon the emergence, growth, and condition of bean, carrot, corn, onion, rye grass, soybean, and wheat seedlings at nominal application rates of up to 0.923 mg/kg soil dw, the highest application rate tested. Based on these findings, the NOEC for those crops was determined to be the nominal application rate of 0.923 mg/kg soil dw. However, the test substance did result in treatment related effects upon cabbage (emergence, growth, and condition), lettuce (condition), and tomato (condition) seedlings at nominal application rates of 0.231 mg/kg soil dw. Based upon these results, the NOEC for cabbage, lettuce, and tomato was determined to be the nominal application rate of 0.115 mg/kg soil dw (equivalent to 35 g a.i./acre or 0.086 kg a.i./ha). 

Reference 2

Endpoint:

toxicity to terrestrial plants: long-term

Type of information:

experimental study

Adequacy of study:

key study

Study period:

23 May 1996 to 27 May 1997

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EPA OPP 122-1 (Terrestrial Plant Toxicity Tier I (vegetative vigor))

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPP 123-1 (Vegetative Vigor Tier II)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

On both application days, samples for the analytical confirmation of test concentrations were collected by pouring from each spray mixture. Triplicate samples of the 18 and 280 g a.i./acre spray mixtures were collected to determine the homogeneity of the spray mixtures.

Vehicle:

no

Details on preparation and application of test substrate:

- Preparation of Spray Mixtures: Spray mixtures for each of the five test concentrations (18, 35, 70, 140, and 280 g a.i./acre, nominal) were prepared from the test substance on September 12 and 13, 1996. On each day, a 3700 mg a.i./L (nominal) solution of the test substance was prepared by diluting the test substance in well water purified by reverse osmosis, followed with mixing by inversion. The 3700 mg a.i./L solution served as the spray mixture for the 280 g a.i./acre application rate treatment group. Spray mixtures for the remaining treatment groups were prepared by diluting aliquots of the 3700 mg a.i./L solution with well water purified by reverse osmosis.

- Application of Spray Mixtures: A pressurized spray applicator was used to spray the soil surface in pots in order to simulate inadvertent direct application or the occurrence of off-target drift resulting from the use of actual field application equipment. The applicator consisted of a pressurized 80 mL polyethylene spray bottle that contained the spray mixture and a boom with two spray nozzles. These parts were connected by various hoses and connectors, and were all mounted on a moveable frame. An external source of compressed carbon dioxide was attached to the applicator and set at 20 psi to force the contents of the spray bottle through the hoses and ultimately out of the applicator via the spray nozzles. A system of valves was used to control the pressurization of the spray bottle and the movement of fluids through the applicator. The applicator was designed to deliver the entire contents of the spray bottle during an application.
Seedlings were placed in a galvanized water tank that served as a protected area for spraying. The vertical walls of the tank reduced interference from air currents, contained the spray within a small area, and supported the frame of the applicator. The applicator was placed across the open top of the water tank with the boom and nozzles suspended over the bottom of the tank. The spray nozzles were suspended approximately 30 cm above the growth pots during delivery of the spray mixture. The tank was lined with an absorbent material (cat litter) to help contain over-spray.
The test substance application in this study was designed to represent four concurrent applications of the test substance at the maximum label rate. Since the label rate indicates a field spray volume of 5 gallons per acre, spray mixtures for this study were applied at a volume of 20 gallons/acre. The spray mixtures for the five treatment groups corresponded to application rates of18, 35, 70, 140, and 280 g a.i./acre of cyproconazole, respectively. The maximum proposed application rate for cyproconazole is 70 g a.i./acre, with a maximum of four applications per year. Applications were made to the control first, followed by applications of spray mixtures from lowest to highest concentration. Species tested at Tier I were sprayed with the control and the 280 g a.i./acre spray mixtures, only. Applications of the test substance were made on September 12 and 13, 1996.

Species:

Phaseolus vulgaris

Plant group:

Dicotyledonae (dicots)

Details on test organisms:

- Common name: Bean
- Family: Fabaceae

Species:

Brassica oleracea var. capitata

Plant group:

Dicotyledonae (dicots)

Details on test organisms:

- Common name: Cabbage
- Family: Cruciferae

Species:

Daucus carota

Plant group:

Dicotyledonae (dicots)

Details on test organisms:

- Common name: Carrot
- Family: Umbelliferae

Species:

Zea mays

Plant group:

Monocotyledonae (monocots)

Details on test organisms:

- Common name: Corn
- Family: Gramineae

Species:

Lactuca sativa

Plant group:

Dicotyledonae (dicots)

Details on test organisms:

- Common name: Lettuce
- Family: Compositae

Species:

Allium cepa

Plant group:

Monocotyledonae (monocots)

Details on test organisms:

- Common name: Onion
- Family: Amaryllidaceae

Species:

Lolium perenne

Plant group:

Monocotyledonae (monocots)

Details on test organisms:

- Common name: Rye Grass
- Family: Gramineae

Species:

Glycine max (G. soja)

Plant group:

Dicotyledonae (dicots)

Details on test organisms:

- Common name: Soybean
- Family: Leguminosae

Species:

Lycopersicon esculentum

Plant group:

Dicotyledonae (dicots)

Details on test organisms:

- Common name: Tomato
- Family: Solanaceae

Species:

Triticum aestivum

Plant group:

Monocotyledonae (monocots)

Details on test organisms:

- Common name: Wheat
- Family: Poaceae

Test type:

vegetative vigour test

Study type:

laboratory study

Substrate type:

artificial soil

Limit test:

no

Total exposure duration:

28 d

Test temperature:

17.8 - 30.6

pH:

Not reported

Moisture:

54% - 84% (Relative Humidity)

Details on test conditions:

TEST SYSTEM
- Test container: Growth pot
- No. of plants: 5
- No. of replicates per treatment group: 3
- No. of replicates per control: 3

SOURCE AND PROPERTIES OF SUBSTRATE (if soil)
- % sand: 90%
- % silt: 5%
- % clay: 5%
- Soil taxonomic classification: Sandy loam (sand, clay, and peat mixed in a 50:4:5 ratio (w:w:w))
- Organic matter: 1.41%
- pH: 7.7

WATER OF PLANTS
Water lost through transpiration and evaporation was replaced by subirrigation with well water from the greenhouse facility. Seedlings were subirrigated to minimize the potential for the leaching of the test substance through the soil. Subirrigation trays were filled to a predetermined depth to help standardize the amount of water delivered to each tray.

GROWTH CONDITIONS
- Photoperiod: The photoperiod was determined by counting the number of hours with light intensity readings greater than 0.001 kW/m2
- Pesticide and Metal Screening of Well Water and Soil: The well water and soil used for plant studies were periodically screened for pesticides and metals. No analytes were measured at levels that were expected to have an impact on the study.

EFFECT PARAMETERS MEASURED
Observations were made during the test to document plant condition and growth. The condition oftest plants was assessed prior to application and weekly thereafter. Plant growth was evaluated by both weekly height measurements and plant shoot fresh and dry weight measurements at test termination.
- Plant Condition: Observations of plant condition were made on Days -1 ( cabbage, carrot, onion, rye grass, soybean, and tomato) or 0 (bean, com, lettuce, and wheat), and on Days 7, 14, 21 and 28. The condition of each seedling was assessed using a numerical score (0 to 100) to indicate the severity of apparent signs of phytotoxicity. Signs of phytotoxicity typically noted included necrosis, leaf curling, or chlorosis. A score of 0 indicated that there was no evidence of phytotoxicity. Scores of 10 to 30 indicated that the effects were slight and not apparently detrimental. Moderate effects were given scores ranging from 40 to 60, whereas severe effects, such as death of leaves, were rated from 70 to 90. Plant deaths were recorded as 100. The mean condition score for each replicate and each treatment group was calculated for each day of observation. The rating system is provided in Table 2 in 'Any other information on materials and methods incl. tabels'.
- Plant Height: Observations of plant heights were made on Days -1 ( cabbage, carrot, onion, rye grass, soybean, and tomato) or O (bean, corn, lettuce, and wheat), and on Days 7, 14, 21 and 28. Plant heights were measured with a ruler to the nearest whole centimetre from the surface of the soil. Soybean and tomato plants were measured to their apical meristem, and bean plants were measured to the base of their most distal open leaf Cabbage, carrot, corn, lettuce, onion, rye grass, and wheat plants were measured to the tip of their tallest leaf The mean height for each replicate and each treatment group was calculated for each day of observation.
- Plant Weights: Measurements of plant weight were made only after test termination, since the procedures used were destructive. Living plants were clipped at soil level, and the above ground (shoot) portion was weighed. After the fresh weight was obtained, plant shoots were placed in a drying oven and dried to a constant weight. The shoot dry weight was then. determined. The mean fresh and dry shoot weights were calculated for each replicate and each treatment group.

Nominal and measured concentrations:

- Nominal concentrations: 0 (negative control), 231, 463, 925, 1850 and 3700 mg a.i./L (corresponding to application rate of 0, 18, 35, 70, 140, and 280 g a.i./acre, respectively)
- Measured concentrations: < LOQ (negative control), 210, 415, 896, 1870 and 3727 mg a.i./L. (corresponding to application rate of 0, 16, 31, 68, 140, and 280 g a.i./acre, respectively)

Reference substance (positive control):

no

Species:

other: Glycine max (G. soja) and Lycopersicon esculentum

Duration:

28 d

Dose descriptor:

NOEC

Effect conc.:

0.086 kg/ha

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

other: Survival and Growth

Remarks on result:

other: Originally reported as 35 g a.i./acre

Species:

Brassica oleracea var. capitata

Duration:

28 d

Dose descriptor:

NOEC

Effect conc.:

0.17 kg/ha

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

other: Survival and Growth

Remarks on result:

other: Originally reported as 70 g a.i./acre

Species:

Phaseolus vulgaris

Duration:

28 d

Dose descriptor:

NOEC

Effect conc.:

0.35 kg/ha

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

other: Survival and Growth

Remarks on result:

other: Originally reported as 180 g a.i./acre

Species:

other: Daucus carota, Zea mays, Lactuca saliva, Allium cepa, Lolium perenne and Triticum aestivum

Duration:

28 d

Dose descriptor:

NOEC

Effect conc.:

0.69 kg/ha

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

other: Survival and Growth

Remarks on result:

other: Originally reported as 280 g a.i./acre

Details on results:

An overview of the results is provided in Table 3 - Table 7 in 'Any other information on results incl. tables'.

Tier I Tests
Tier I tests were conducted with the test substance to evaluate the potential for effects upon the condition and growth of carrot, com, onion, and rye grass when applied at a nominal application rate of 280 g a.i./acre There were no apparent treatment related effects upon carrot, com, onion, or rye grass seedlings at the 280 g a.i./acre application rate, and any differences from the controls were slight and were not statistically significant (p > 0.05). The NOEC for condition and growth of carrot, corn, onion, and rye grass seedlings in this study was determined to be the nominal application rate of 280 g a.i./A, the highest concentration tested.

Tier II Tests
Tier II tests were conducted on bean, cabbage, lettuce, soybean, tomato, and wheat.
- Bean: There were no apparent treatment related effects upon the condition or growth of beans at the nominal application rates of 18, 35, 70, or 140 g a.i./acre. Slight chlorosis, necrosis, and leaf curl were apparent in the 18, 35, 70, and 140 g.a.i./acre treatment groups, but these conditions were not believed to be treatment related since they also were apparent in the control group. A more likely explanation for these changes in condition was normal leaf senescence or insect damage. There were apparent treatment related effects upon the condition of plants at the nominal
280 g a.i./acre application rate. Chlorosis, necrosis, and leaf curl were more severe and appeared earlier in the nominal 280 g.a.i./acre treatment group than in the control and other treatment groups. The group mean condition score for the nominal 280 g a.i./acre group was highest on Day 14 of the study (21.3, compared to 2.7 for the control group mean), and was significantly (p < 0.01) different from the control group mean on Days 14, 21, and 28. There were no corresponding growth reductions observed in the nominal 280 g a.i./acre group, therefore, the effects appeared to be limited to the observed leaf damage.
Based on the observed effects on plant condition, the LOEC for beans was determined to be 280 g a.i./acre, and the NOEC was determined to be 140 g a.i./acre. There was insufficient response in plant growth to calculate meaningful EC10, EC25, EC50, or EC90 values.

- Cabbage: There were no apparent treatment related effects upon cabbage seedlings at the nominal application rates of 18, 35, or 70 g a.i./acre. There were a few observations of chlorosis and necrosis among plants in the control and nominal 18 and 35 g a.i./acre treatment groups, but the observations were attributed to insect damage and were not considered to be treatment related. One seedling in the nominal 70 g a.i./acre treatment group was slightly necrotic from Day 14 until the test was terminated on Day 28. The cause of the necrosis was not determined, and there was no apparent damage to the overall vigour of the plant. The mean shoot weights (fresh and dry) of the nominal 35 and 70 g a.i./acre groups were reduced relative to the control group mean, but the differences were small and not statistically significant (p > 0.05) and therefore not considered treatment related. However, there were apparent treatment related effects in the condition of seedlings at the two highest treatment levels. Necrotic patches along leaf margins were observed in both the nominal 140 and 280 g a.i./ acre treatment groups. The necrosis in both groups resulted in elevated mean condition scores, however, the only statistically significant (0.01 < p < 0.05) differences-observed were those between the mean scores of the nominal 280 g a.i./acre group and the control group on Days 21 and 28.
There also were apparently treatment related reductions in growth (fresh and dry weights) observed in the nominal 140 and 280 g a.i./acre treatment groups. Mean fresh weights in these groups were 82 and 75% of the control mean, respectively. Mean dry weights in the nominal 140 and 280 g a.i./acre treatment groups were 78 and 76% of the control mean, respectively. The mean dry weight of the 280 g a.i./acre group was significantly different (0.01 < p < 0.05) from the control mean. Mean height of the nominal 140 g a.i./acre group was reduced and significantly different (p < 0.05) from the control mean on Days 7 and 14, however, the difference was not attributed to treatment. On Days 21 and 28 there were no significant (p > 0.05) differences in mean height between the control and any of the treatment groups. Based upon the observed effects on plant condition and growth, the LOEC for cabbage was determined to be 140 g a.i./acre, and the NOEC was determined to be 70 g a.i./acre. There was insufficient response in these variables to calculate meaningful EC10, EC25, EC50, or EC90 values.

- Lettuce: There were no apparent treatment related effects upon the condition or growth of lettuce plants at any application rate tested. Normal leaf senescence resulted in slight necrosis, chlorosis, and leaf curl in all treatment groups including the control. Slight differences in both condition and height were observed between the control and some of the treatment groups. However, the differences were small and did not appear to be dose responsive and therefore were not considered to be treatment related. The highest nominal application rate tested, 280 g a.i./acre, was determined to be a NOEC for lettuce. There was insufficient response in these variables to calculate meaningful EC10, EC25, EC50, or EC90 values.

- Soybean: There were no apparent treatment related effects upon the growth of plants at any application rate tested. However, there were apparent treatment related effects on the condition of plants in the 70, 140 and 280 g a.i./acre treatment groups. The affected plants in these treatment groups had a type of leaf curl that was characterized by a roughened, corrugated appearance to the leaf surface. Normal leaf senescence and insect damage resulted in slight necrosis, chlorosis, and leaf curl in the control and treatment groups. However, the leaf curl associated with insect damage and leaf senescence was characterized by leaves rolling into a "C" shape along the mid-vein. The two types of leaf curl were distinguishable and only the leaf curl characterized by a roughened, corrugated appearance to the leaf surface was considered to be treatment related. Based upon the observed effects on plant condition, the LOEC for soybeans was determined to be 70 g a.i./acre and the NOEC was determined to be 35 g a.i./acre. There was insufficient response in height, fresh weight, or dry weight to calculate meaningful EC10, EC25, EC50, or EC90 values.

- Tomato: There were no treatment related effects on plant growth at any application rate tested.
However, there were apparent treatment related effects on the condition of plants in the 70, 140 and 280 g a.i./acre treatment groups. The affected plants in these treatment groups had a type of leaf curl that was characterized by a roughened, corrugated appearance to the leaf surface. This type of leaf curl was similar to the type of leaf curl observed in affected soybean plants.
Slight necrosis, chlorosis, stem curl and leaf curl were occasionally observed in the control and treatment groups. These conditions were not attributed to treatment because of the relatively few plants affected and because they also were observed in the control group. The leaf curl associated with the lower treatment levels and the control was characterized by leaves rolling into a "C" shape along the mid-vein. This type of leaf curl was easily distinguished from the leaf curl that was attributed to treatment and characterized by a roughened, corrugated appearance to the leaf surface.
Because of the observed effects on plant condition, LOEC was for tomato was determined to be 70 g a.i./acre (nominal), while the NOEC was determined to be 35 g a.i./acre. There was insufficient response in height, fresh weight, or dry weight to calculate meaningful EC10, EC25, EC50, or EC90 values.

- Wheat: There were no apparent treatment related effects on the condition or growth of wheat plants at any application rate tested. Although chlorosis and necrosis were observed during the test, the signs were slight and there were very few affected plants. Therefore, the chlorosis and necrosis were considered incidental to treatment. The highest nominal application rate tested, 280 g a.i./acre, was determined to be the NOEC for wheat. There was insufficient response to calculate meaningful EC10, EC25, EC50, or EC90 estimates for height, fresh weight, or dry weight.

Reported statistics and error estimates:

See Data Analysis in 'Any other information on materials and methods incl. tables'

Table 3. Mean plant condition scores (Tire I) a

Species	Nominal application rate (g a.i./acre	Preapplication Mean ± SD	Day 7 Mean ± SD	Day 14 Mean ± SD	Day 21 Mean ± SD	Day 28 Mean ± SD
Carrot	0 (Control)   280	0 ± 0.0   0 ± 0.0	0 ± 0.0   0 ± 0.0	0 ± 0.0   0 ± 0.0	0 ± 0.0   1 ± 1.2	0 ± 0.0   0 ± 0.0
Corn	0 (Control)   280	0 ± 0.0   0 ± 0.0	3 ± 1.2   1 ± 1.2	9 ± 1.2   9 ± 1.2	0 ± 0.0   0 ± 0.0	0 ± 0.0   0 ± 0.0
Onion	0 (Control)   280	0 ± 0.0   0 ± 0.0	0 ± 0.0   0 ± 0.0	0 ± 0.0   0 ± 0.0	0 ± 0.0   0 ± 0.0	0 ± 0.0   1 ± 1.2
Rye Grass	0 (Control)   280	0 ± 0.0   0 ± 0.0	1 ± 1.2   0 ± 0.0	0 ± 0.0   0 ± 0.0	0 ± 0.0   0 ± 0.0	0 ± 0.0   0 ± 0.0

a The condition of each plant was assessed using a numerical score (0 to 100) to indicate the severity of apparent signs of phytotoxicity. A score of O represents a healthy plant while 100 represents a dead plant.

Treatment means were not significantly different from controls. (T-test, alpha= 0.05)

Table 4. Mean plant height (cm)

Species	Application Rate (g a.i./acre)	Preapplication Mean ± SD	Day 7 Mean ± SD	Day 14 Mean ± SD	Day 21 Mean ± SD	Day 28
						Mean ± SD	95% CL Lower	95% CL Upper	% Inhibition
Carrot	0(Control)   280	9.1 ± 0.5   8.5 ± 0.8	14.9 ± 0.9   14.4 ± 0.9	17.7 ± 1.8   16.7 ± 1.5	22.2 ± 1.9   21.7 ± 1.8	26.5 ± 3.1   24.7 ± 1.7	18.7   20.4	34.2   28.9	--   7
Corn	0 (Control)   280	25.0 ± 0.5   24.7 ± 2.5	50.8 ± 2.1   51.0 ± 3.7	72.0 ± 1.8   72.1 ± 1.8	93.6 ± 1.4   91.7 ± 1.6	106.8 ± 1.9   103.7 ± 1.1	102.0   100.9	111.6   106.6	--   3
Onion	0 (Control)   280	7.3 ± 0.9   7.6 ± 0.4	11.3 ± 2.7   11.9 ± 0.7	15.7 ± 1.4   16.1 ± 0.6	21.3 ± 2.0   20.7 ± 0.9	25.2 ± 2.6   25.1 ± 0.6	18.9   23.6	31.5   26.7	--   0
Rye Grass	0 (Control)   280	11.5 ± 0.5   11.1 ± 0.8	16.1 ± 1.4   16.7 ± 0.8	21.1 ± 1.4   20.5 ± 0.4	27.1 ± 2.6   26.5 ± 0.3	27.9 ± 2.9   27.9 ± 0.4	20.7   26.8	35.2   28.9	--   0

Treatment means were not significantly different from controls. (T-test, alpha= 0.05)

Table 5. Mean weight of shoots collected at test termination (g)

Species	Application Rate (g a.i./acre)	Fresh Weight				Dry weight
		Mean ± SD	95% CL Lower	95% CL Upper	% Inhibition	Mean ± SD	95% CL Lower	95% CL Upper	% Inhibition
Carrot	0 (Control)   280	6.18 ± 1.09   5.28 ± 1.20	3.47   2.31	8.90   8.25	-   15	1.01 ± 0.17   0.89 ± 0.19	0.59   0.43	1.42   1.35	--   12
		85% a				88%
Com	0 (Control)   280	61.50 ± 1.52   56.04 ± 4.39	57.71   45.12	65.28   66.95	--   9	7.62 ± 0.21   7.36 ± 0.66	7.10   5.72	8.15   9.00	--   4
		91%				96%
Onion	0 (Control)   280	1.76 ± 0.59   1.64 ± 0.12	0.29   1.35	3.23   1.94	--   7	0.11 ± 0.03   0.10 ± 0.00	0.03   0.09	0.19   0.11	--   9
		93%				91%
Rye Grass	0 (Control)   280	5.22 ± 0.93   4.51 ± 0.47	2.91   3.35	7.54   5.68	--   14	0.83 ± 0.15   0.72± 0.08	0.45   0.53	1.20   0.91	--   13
		86%				87%

a. Percent of control value.

Treatment means were not significantly different from controls. (T-test, alpha= 0.05)

Table 6.Observed NOEC and Calculated EC10 Estimates¹for the test substance(g a.i./acre) on Seedlings

Species	Parameter	NOEC (g a.i./acre, nominal)	Calculatecl^2ECx Estimates
			EC10 (95%CI)	EC25, EC50 and EC90
Bean	Condition	140	-	-
	Height	140	14.7 (7.46 – 91.1)	> 280
	Fresh weight	140	> 280	> 280
	Dry weight	140	> 280	> 280
Cabbage	Condition	70	-	-
	Height	70	259 (ND^3)	> 280
	Fresh weight	70	61.3 (14.2 - 146)	> 280
	Dry weight	70	47.4 (14.9 - 104)	> 280
Lettuce	Condition	280	-	-
	Height	280	> 280	> 280
	Fresh weight	280	12.3 (ND)	> 280
	Dry weight	280	> 280	> 280
Soybean	Condition	35	-	-
	Height	280	> 280	> 280
	Fresh weight	280	> 280	> 280
	Dry weight	280	> 280	> 280
Tomato	Condition	35	-	-
	Height	280	> 280	> 280
	Fresh weight	280	> 280	> 280
	Dry weight	280	227 (ND)	> 280
Wheat	Condition	280	-	-
	Height	280	> 280	> 280
	Fresh weight	280	> 280	> 280
	Dry weight	280	> 280	> 280

1.The NOEC is defined as the highest test concentration with no observable treatment related effects, and therefore may not take on values between test concentrations. Calculated ECx estimates are not always consistent with NOEC determinations. For example, a calculated 10% difference (EC10) may not be meaningful or observable due to variability in the data. Additionally, NOEC determinations may be based upon qualitative assessments of plant condition which are not included in the ECx calculations .

2 Since plant condition is a qualitative assessment, only the NOEC was determined and reported.

3.The method used by ICPIN could not determine 95% confidence limits.

Table 7 Mean plant condition score, mean plant height and mean plant weight (Tier II, bean)

Application rate^1  (g a.i./acre)	Condition score^2	Plant height (mm) Day 28				Fresh Weight (g)				Dry Weight (g)
	Day 28      Mean ± SD	Mean ± SD	95%CL	95%CL	Inhibition %	Mean ± SD	95%CL		%	Mean ± SD	95%CL		%
			Lower	Upper			Lower	Upper	Inhibition		Lower	Upper	Inhibition
0 (Control)	5 ± 4.2	127.7 ± 10.0	102.8	152.6	--	38.89 ± 2.17	33.5	44.28	-	7.83 ± 0.22	7.29	8.37
16	9 ± 2.3	113.5 ± 21.5	60.1	166.9	11	39.96 ± 2.32	34.2	45.71	-3	7.84 ± 0.27	7.15	8.52	0
		89%^3				103% 2				100%
31	9 ± 1.2	101.5 ± 21.7	47.5	155.5	20	40.98 ± 1.17	38.09	43.88	-5	8.24 ± 0.32	7.46	9.03	-5
		80%				105%				105%
68	13 ± 3.1***	113.4 ± 7.3	95.3	131.5	11	39.91 ± 0.57	38.5	41.33	-3	8.07 ± 0.29	7.34	8.8	-3
		89%				103%				103%
140	14 ± 0.0***	99.3 ± 5.9	84.5	114.0	22	36.77 ± 2.83	29.75	43.79	5	7.47 ± 0.59	6.01	8.92	5
		78%				95%				95%
280	16 ± 2.0***	108.4 ± 0.9	106.1	110.7	15	38.04 ± 1.27	34.89	41.2	2	7.56 ± 0.47	6.4	8.71	4
		85%				98%				96%

1. Application rates based on measured concentrations of the test substance in spray mixtures.

2. The condition of each plant was assessed using a numerical score (0 to 100) to indicate the severity of apparent signs of phytotoxicity. A score of 0 represents a healthy plant while 100 represents a dead plant.

3. Percent of control value.

*** Mean significantly different from control. (Dunnett's two-tailed test, alpha= 0.01)

Table 8. Mean plant condition score, mean plant height and mean plant weight (Tier II, cabbage)

Application rate (g a.i./acre)^1	Condition score^2	Plant height (mm) Day 28				Fresh Weight (g)				Dry Weight (g)
	Day 28    Mean ± SD	Mean ± SD	95%CL	95%CL	Inhibition %	Mean ± SD	95%CL		% Inhibition	Mean ± SD	95%CL		% Inhibition
			Lower	Upper			Lower	Upper			Lower	Upper
0 (Control)	0 ± 0.0	14.9 ± 0.9	12.5	17.2	--	22.03 ± 4.23	11.53	32.53	-	2.69 ± 0.40	1.71	3.67
16	1 ± 1.2	15.1 ± 0.8	13.1	17.2	-2	22.07 ± 1.21	19.07	25.07	0	2.62 ± 0.11	2.36	2.89	2
		102%^3				100%^3				98%
31	1 ± 1.2	14.4 ± 1.1	11.8	14	3	20.50 ± 3.92	10.77	30.23	7	2.46 ± 0.30	1.71	3.20	9
		97%				93%				91%
68	1 ± 1.2	14.3 ± 1.2	11.4	17.1	4	19.70 ± 2.84	12.64	26.76	11	2.32 ± 0.35	1.45	3.18	14
		96%				89%				86%
140	3 ± 3.1	14.6 ± 0.4	13.6	15.6	2	18.12 ± 1.79	13.68	22.56	18	2.10 ± 0.19	1.64	2.57	22
		98%				82%				78%
280	6 ± 3.5**	13.5 ± 0.7	11.7	15.2	9	16.56 ±1.22	13.52	19.60	25	2.04 ± 0.16**	1.65	2.44	24
		91%				75%				76%

1 Application rates based on measured concentrations of the test substance in spray mixtures.

2. The condition of each plant was assessed using a numerical score (0 to 100) to indicate the severity of apparent signs of phytotoxicity. A score of 0 represents a healthy plant while 100 represents a dead plant.

3. Percent of control value.

** Mean significantly different from control. (Dunnett's two-tailed test, alpha= 0.05)

Table 9. Mean plant condition score, mean plant height and mean plant weight (Tier II, Lettuce)

Application rate^1  (g a.i./acre)	Condition score^2	Plant height (mm) Day 28				Fresh Weight (g)				Dry Weight (g)
	Day 28      Mean ± SD	Mean ± SD	95%CL	95%CL	Inhibition %	Mean ± SD	95%CL		%	Mean ± SD	95%CL		%
			Lower	Upper			Lower	Upper	Inhibition		Lower	Upper	Inhibition
0 (Control)	1 ± 2.3	24.3 ± 1.2	21.2	27.3	--	44.01 ± 5.82	11.53	32.53	-	1.61 ± 0.28	1.71	3.67
16	1 ± 1.2	23.0 ± 0.3	22.1	23.9	5	37.21 ± 4.74	19.07	25.07	15	1.39 ± 0.17	2.36	2.89	13
		95%^3				85%				87%
31	1 ± 1.2	23.3 ± 0.6	21.8	24.9	4	39.16 ± 1.64	10.77	30.23	11	1.40 ± 0.12	1.71	3.2	13
		96%				89%				87%
68	1 ± 2.3	21.9 ± 0.5	20.7	23.2	10	31.90 ± 5.39	12.64	26.76	28	1.52 ± 0.19	1.45	3.18	5
		90%				72%				94%
140	3 ± 1.2	23.1 ± 2.8	16	30.1	5	35.28 ± 9.01	13.68	22.56	20	1.64 ± 0.25	1.64	2.57	-2
		95%				80%				102%
280	4 ± 2.2**	22.5 ± 1.3	19.3	25.7	7	36.42 ± 1.37	13.52	19.6	17	1.64 ± 0.03	1.65	2.44	-3
		93%				83%				102%

1. Application rates based on measured concentrations of the test substance in spray mixtures.

2. The condition of each plant was assessed using a numerical score (0 to 100) to indicate the severity of apparent signs of phytotoxicity. A score of 0 represents a healthy plant while 100 represents a dead plant.

3. Percent of control value.

** Mean significantly different from control. (Dunnett's two-tailed test, alpha= 0.05)

  Table 10. Mean plant condition score, mean plant height and mean plant weight (Tier II, Soybean)

Application rate^1  (g a.i./acre)	Condition score^2	Plant height (mm) Day 28				Fresh Weight (g)				Dry Weight (g)
	Day 28     Mean ± SD	Mean ± SD	95%CL	95%CL	Inhibition %	Mean ± SD	95%CL		%	Mean ± SD	95%CL		%
			Lower	Upper			Lower	Upper	Inhibition		Lower	Upper	Inhibition
0 (Control)	14 ± 5.3	30.0 ± 3.9	20.4	39.6	--	16.80 ± 1.28	13.61	19.99	-	3.48 ± 0.26	2.84	4.12	--
16	11 ± 2.3	29.5 ± 1.0	26.9	32.0	2	17.53 ± 0.58	16.10	18.96	-4	3.56 ± 0.11	3.27	3.84	-2
		98%^3				104%				102%
31	8 ± 2.0	28.1 ± 0.8	26.3	30.0	6	17.50 ± 0.39	16.53	18.47	-4	3.64 ± 0.09	3.42	3.87	-5
		94%				104%				105%
68	13 ± 4.6	27.9 ± 2.5	21.6	34.2	7	16.37 ± 2.54	10.07	22.67	3	3.38 ± 0.53	2.07	4.70	3
		93%				97%				97%
140	13 ± 4.6	28.7 ± 3.0	21.3	36.2	4	16.32 ± 1.90	11.59	21.05	3	3.34 ± 0.48	2.16	4.53	4
		96%				97%				96%
280	11 ± 1.2	28.8 ± 2.0	23.9	33.7	4	17.12 ± 3.19	9.19	25.05	-2	3.49 ± 0.58	2.05	4.94	0
		96%				102%				100%

1. Application rates based on measured concentrations of the test substance in spray mixtures.

2. The condition of each plant was assessed using a numerical score (0 to 100) to indicate the severity of apparent signs of phytotoxicity. A score of 0 represents a healthy plant while 100 represents a dead plant.

3. Percent of control value.

** Mean significantly different from control. (Dunnett's two-tailed test, alpha= 0.05)

  Table 11. Mean plant condition score, mean plant height and mean plant weight (Tier II, tomato)

Application rate^1  (g a.i./acre)	Condition score^2	Plant height (mm) Day 28				Fresh Weight (g)				Dry Weight (g)
	Day 28     Mean ± SD	Mean ± SD	95%CL	95%CL	Inhibition %	Mean ± SD	95%CL		%	Mean ± SD	95%CL		%
			Lower	Upper			Lower	Upper	Inhibition		Lower	Upper	Inhibition
0 (Control)	1 ± 2.3	33.0±2.3	27.3	38.7	--	38.83±1.68	34.65	43.00	-	4.66±0.14	4.31	5.02	--
16	1 ± 2.3	33.1±1.3	29.8	36.4	0	39.15±1.74	34.83	43.46	-1	4.68±0.37	3.77	5.59	0
		100%^3				101%				100%
31	1 ± 1.2	32.4±2.5	26.3	38.5	2	37.39±2.64	30.82	43.96	4	4.82±0.50	3.57	6.06	-3
		98%				96%				103%
68	1 ± 1.2	32.1±2.8	25.1	39.0	3	37.46±5.70	23.31	51.62	4	4.61±0.99	2.16	7.06	1
		97%				96%				99%
140	3 ± 3.1	34.4±1.8	30.0	38.8	-4	37.39±3.45	28.81	45.97	4	4.54±0.14	4.19	4.88	3
		104%				96%				97%
280	7 ± 1.2**	33.1±3.4	24.6	41.5	0	37.71±3.19	29.77	45.64	3	4.14±0.48	2.95	5.33	11
		100%				97%				89%

1. Application rates based on measured concentrations of the test substance in spray mixtures.

2. The condition of each plant was assessed using a numerical score (0 to 100) to indicate the severity of apparent signs of phytotoxicity. A score of 0 represents a healthy plant while 100 represents a dead plant.

3. Percent of control value.

** Mean significantly different from control. (Dunnett's two-tailed test, alpha= 0.05)

  Table 12. Mean plant condition score, mean plant height and mean plant weight (Tier II, wheat)

Application rate^1  (g a.i./acre)	Condition score^2	Plant height (mm) Day 28				Fresh Weight (g)				Dry Weight (g)
	Day 28     Mean ± SD	Mean ± SD	95%CL	95%CL	Inhibition %	Mean ± SD	95%CL		%	Mean ± SD	95%CL		%
			Lower	Upper			Lower	Upper	Inhibition		Lower	Upper	Inhibition
0 (Control)	0 ± 0.0	50.7 ± 3.8	41.3	60.0	--	19.17 ± 1.05	16.56	21.78	-	2.95 ± 0.13	2.64	3.27	--
16	0 ± 0.0	47.9 ± 2.5	41.6	54.3	5	19.32 ± 0.70	17.59	21.06	-1	2.98 ± 0.05	2.87	3.10	-1
		95%^3				101%				101%
31	0 ± 0.0	48.7 ± 2.0	43.6	53.7	4	17.81 ± 0.19	17.33	18.29	7	2.77 ± 0.09	2.55	2.99	6
		96%				93%				94%
68	0 ± 0.0	49.1 ± 3.1	41.4	56.9	3	20.02 ± 3.31	11.80	28.25	-4	3.06 ± 0.50	1.81	4.30	-3
		97%				104%				103%
140	0 ± 0.0	50.7 ± 2.4	44.8	56.7	0	18.84 ± 2.04	13.77	23.90	2	2.77 ± 0.22	2.23	3.32	6
		100%				98%				94%
280	0 ± 0.0	49.0 ± 0.7	47.2	50.8	3	18.56 ± 0.57	17.13	19.98	3	2.79 ± 0.10	2.55	3.04	5
		97%				97%				95%

1. Application rates based on measured concentrations of the test substance in spray mixtures.

2. The condition of each plant was assessed using a numerical score (0 to 100) to indicate the severity of apparent signs of phytotoxicity. A score of 0 represents a healthy plant while 100 represents a dead plant.

3. Percent of control value.

** Mean significantly different from control. (Dunnett's two-tailed test, alpha= 0.05)

 

 

Validity criteria fulfilled:

yes

Conclusions:

Based on these findings, the NOEC for carrot, corn, lettuce, onion, rye grass, and wheat was determined to be 0.69 kg/ha (equivalent to 280 g a.i./acre) and the NOEC for beans, cabbage, soybeans, and tomato were determined to be 0.35, 0.17, 0.086 and 0.086 kg/ha (equivalent to140, 70, 35, and 35 g/acre), respectively.

Executive summary:

A vegetative vigour study was performed to determine the effects of the test substance (320SC) on the survival and growth (wet weight, dry weight, condition and height) of ten plants (four monocotyledonae and six dicotyledonae plant species). This study followed FIFRA 122-1 & 123 -1 guidelines and compliant with GLP criteria. Four plant species (carrot, corn, onion, and rye grass) were tested under Tier I (FIFRA Subdivision J, Series 122-1) conditions, which consisted of a single nominal test substance concentration (0.69 kg a.i./ha, equivalent to 280 g a.i./acre) and a control. Six species (bean, cabbage, lettuce, soybean, tomato, and wheat) were tested under Tier II (FIFRA Subdivision J, Series 123-1) conditions, which consisted of a series of five nominal test concentrations (0.044, 0.086, 0.17, 0.35 and 0.69 kg a.i./ha, equivalent to 18, 35, 70, 140, 280 g a.i./acre, respectively) and a control group. A single application of the test substance was made to the plants in each treatment group. Seedlings were randomly assigned to treatment groups just prior to test initiation. The replicate pots were placed in a randomised block design on greenhouse tables after spray mixtures were applied. Actual concentrations of the spray mixtures were analytically determined from samples collected from the treatment and control groups on Day 0 (concentrations were in the range of 94 - 117% of nominal). Observations of height and condition were made on Days -1 or 0 (prior to application), 7, 14, 21, and 28, while observations of fresh shoot weight were only made on Day 28. After the fresh shoot weight was determined, plant material was dried to a constant weight and dry shoot weight was measured, too.  

The results showed that the test substance had no apparent treatment related effects upon the plant condition and growth of carrot, corn, lettuce, onion, rye grass, and wheat seedlings at nominal application rates of up to 0.69 kg a.i./ha, the highest application rate tested. Based on these findings, the NOEC for those crops was determined to be 0.69 kg a.i./ha. The test substance did result in treatment related effects upon beans (chlorosis, necrosis and leaf curl) at the nominal application rate of 0.69 kg a.i./ha. Apparent treatment related effects in cabbage (necrosis, fresh and dry weight) were observed at the nominal application rate of 0.35 kg a.i./ha. Apparent treatment related effects were also observed in soybean (leaf curl) and tomato (leaf curl) seedlings at the nominal application rate of 0.17 kg a.i./ha. Based upon these results the NOEC for beans, cabbage, soybeans, and tomato was determined to be the nominal application rates of 0.35, 0.17, 0.086 and 0.086 kg a.i./ha, equivalent to 140, 70, 35, and 35 g a.i./ acre, respectively.

Description of key information

14-d NOEC = 0.115 mg/kg soil dw), seedling emergence test, survival, emergence and growth (wet weight, dry weight, height and condition), FIFRA 122 -1&123 -1, Porch, 1997

14-d EC50 > 0.92 mg/kg soil dw, seedling emergence test, survival, emergence and growth (wet weight, dry weight, height and condition), FIFRA 122 -1&123 -1, Porch, 1997

28-d NOEC = 0.086 kg/ha, vegetative vigour test, survival and growth (wet weight, dry weight, height and condition), FIFRA 122 -1&123 -1, Porch, 1997

Key value for chemical safety assessment

Long-term EC10, LC10 or NOEC for terrestrial plants:

0.115 mg/kg soil dw

Additional information

Seedling emergence

The effects of the test substance (320 SC) on the survival, emergence and growth of ten plants species was studied by following FIFRA 122-1 and 123-1 guidelines. The study was compliance with GLP criteria. In total, ten plant species (four monocotyledonae and six dicotyledonae plant species) were included in this study. Seven plant species (bean, carrot, corn, lettuce, onion, soybean, and wheat), were tested at Tier I (FIFRA Subdivision J, Series 122-1), which consisted of a single test substance concentration (280g a.i./acre equivalent to 0.92 mg/kg soil dw) and a negative control. Four species (cabbage, lettuce, rye grass, and tomato) were tested at Tier II (FIFRA Subdivision J, Series 123-1), which consisted of a series of five nominal test concentrations (18, 35, 70, 140, and 280 g a.i./acre equivalent to 0.059, 0.115, 0.231, 0.461 and 0.923 mg/kg soil dw) and a negative control group. For each species tested, one application of each of the various treatments was made by spraying the soil with the appropriate concentration of aqueous spray mixtures of the test substance. During the test, phytotoxic effects of the test substance on seedling emergence and growth of emerged seedlings were evaluated. The test duration was extended for onions and lettuce to allow for adequate time for germination and emergence. 

The results showed that the test substance had no apparent treatment related effects upon the emergence, growth, and condition of bean, carrot, corn, onion, rye grass, soybean, and wheat seedlings at nominal application rates of up to 0.923 mg/kg soil dw, the highest application rate tested. Based on these findings, the NOEC for those crops was determined to be the nominal application rate of 0.923 mg/kg soil dw. However, the test substance did result in treatment related effects upon cabbage (emergence, growth, and condition), lettuce (condition), and tomato (condition) seedlings at nominal application rates of 0.231 mg/kg soil dw. Based upon these results, the NOEC for cabbage, lettuce, and tomato was determined to be the nominal application rate of 0.115 mg/kg soil dw (equivalent to 35 g a.i./acre or 0.086 kg a.i./ha). 

 

Vegetative vigour

A vegetative vigour study was performed to determine the effects of the test substance (320 SC) on the survival and growth (wet weight, dry weight, condition and height) of ten plants (four monocotyledonae and six dicotyledonae plant species). This study followed FIFRA 122-1 & 123 -1 guidelines and compliant with GLP criteria. Four plant species (carrot, corn, onion, and rye grass) were tested under Tier I (FIFRA Subdivision J, Series 122-1) conditions, which consisted of a single nominal test substance concentration (0.69 kg a.i./ha, equivalent to 280 g a.i./acre) and a control. Six species (bean, cabbage, lettuce, soybean, tomato, and wheat) were tested under Tier II (FIFRA Subdivision J, Series 123-1) conditions, which consisted of a series of five nominal test concentrations (0.044, 0.086, 0.17, 0.35 and 0.69 kg a.i./ha, equivalent to 18, 35, 70, 140, 280 g a.i./acre, respectively) and a control group. A single application of the test substance was made to the plants in each treatment group. Seedlings were randomly assigned to treatment groups just prior to test initiation. The replicate pots were placed in a randomised block design on greenhouse tables after spray mixtures were applied. Actual concentrations of the spray mixtures were analytically determined from samples collected from the treatment and control groups on Day 0 (concentrations were in the range of 94 - 117% of nominal). Observations of height and condition were made on Days -1 or 0 (prior to application), 7, 14, 21, and 28, while observations of fresh shoot weight were only made on Day 28. After the fresh shoot weight was determined, plant material was dried to a constant weight and dry shoot weight was measured, too.  

The results showed that the test substance had no apparent treatment related effects upon the plant condition and growth of carrot, corn, lettuce, onion, rye grass, and wheat seedlings at nominal application rates of up to 0.69 kg a.i./ha, the highest application rate tested. Based on these findings, the NOEC for those crops was determined to be 0.69 kg a.i./ha. The test substance did result in treatment related effects upon beans (chlorosis, necrosis and leaf curl) at the nominal application rate of 0.69 kg a.i./ha. Apparent treatment related effects in cabbage (necrosis, fresh and dry weight) were observed at the nominal application rate of 0.35 kg a.i./ha. Apparent treatment related effects were also observed in soybean (leaf curl) and tomato (leaf curl) seedlings at the nominal application rate of 0.17 kg a.i./ha. Based upon these results the NOEC for beans, cabbage, soybeans, and tomato was determined to be the nominal application rates of 0.35, 0.17, 0.086 and 0.086 kg a.i./ha, equivalent to 140, 70, 35, and 35 g a.i./ acre, respectively.