Vegetable crops

Numerous field trials were conducted at various locations throughout the USA from 1991 to 1993 (Chen et ai, 1994c,d; Dong, 1995b,c). Ground applications were either by foliar spray or directly to the soil at intervals of 5 to 10 days. Single samples at each PHI were analysed. The proposed use pattern for leafy vegetables and cole crops in the USA is 7 applications at 0.067-0.135 kg ai/ha with a 7-day PHI.

Celery. In trials by Chen et al. (1994d) plot sizes were 0.15-0.74 ha. In two trials samples of both stalk and stalk with foliage were analysed for comparison, while in the others only stalk samples were analysed. Analyses were by HPLC with an LOD of 0.05 mg/kg. The interval from sampling to analysis (SAI) ranged from 150 to 525 days.

Dong (1995c) compared the 2SC and 70WP formulations in the USA in 1994-5 with 7 to 9 applications at a rate of 0.140 kg ai/ha. The plot sizes were 0.74 to 1.24 ha. The SAI was 71-350 days.

The residues of tebufenozide from trials approximating proposed GAP ranged from 0.1 to 0.6 mg/kg in the stalk and were 0.4 and 1.3 mg/kg in stalk with foliage. Two samples of stalk were analysed for RH-0897. Both contained <0.01 mg/kg.

Table 26. Residues of tebufenozide in celery, USA, 1992-1995.

State, year	Form.	Application			PHI, days	Residue, mg/kg	Reference
		No.	kg ai/ha	kg ai/hl
MI	SC	7	0.14	0.045-0.047	0	1.4	Chen, 1994d
1992					6	0.47
PL	SC	7	0.14	0.015	9	0.1	Chen, 1994d
1992-1993
CA	SC	7	0.14	0.030	0	2.3*	Chen, 1994d
1993					7	1.3*
					0	0.29
					7	0.49
MI	SC	8	0.14	0.05-0.055	0	1.2	Chen, 1994d
1993					6	1.2
					13	0.64
CA	SC	8	0.14	0.075	0	1.2*	Chen, 1994d
1993					7	0.41*
					0	0.15
					7	0.09
MI	SC	8	0.28	0.100-0.111	0	4.5	Chen, 1994d
1993					6	3.2
					13	1.5
CA	SC	7	0.14	0.025	0	0.38	Dong, 1995c
1994					7	0.64
CA	WP	7	0.14	0.025	0	0.47	Dong, 1995c
1994					7	0.6
PL	SC	9	0.14	0.05	0	0.08	Dong, 1995c
1995					7	0.04
PL	WP	9	0.14	0.05	0	0.08	Dong, 1995c
1995					7	0.05

* stalk with foliage

Lettuce. Six field trials with head lettuce and four with leaf lettuce were carried out at different locations in the USA (Chen et al., 1994d). The plot sizes ranged from 0.52 to 1.68 ha. In three of the head lettuce trials samples with and without wrapper leaves were analysed and in the other three only samples with wrapper leaves. The LOD was 0.01 mg/kg and the SAI ranged from 246 days to just over three years. In three samples analysed for RH-0897 the residues were all below the LOD of 0.01 mg/kg.

Two trials on head lettuce with wrapper leaves and two on leaf lettuce were conducted with tebufenozide formulated as the 2SC and 70WP at 0.14 kg ai/ha (Dong, 1995c). The SAI ranged from 178 to 344 days.

Residues from 7-8 applications at 0.14 kg ai/ha, at a 7-day PHI, in head lettuce ranged from <0.01 mg/kg without wrapper leaves to 6.6 mg/kg wrapper leaves, and in leaf lettuce from 1.1 to 3.2 mg/kg.

Table 27. Residues of tebufenozide in head lettuce, USA, 1991-1994.

State Year	Form.	Application			PHI, days	Residue, mg/kg	Reference
		No.	kg ai/ha	kg ai/hl
NJ	SC	7	0.14	0.043	0	0.031	Chen, 1994d
1991					7	0.0091
					0	0.48
					7	0.092
CA	SC	5	0.14	0.075	30	<0.01	Chen, 1994d
1991
CA	SC	8	0.14	0.075	0	1.71	Chen, 1994d
1991					7	0.0531
					0	5.1
					7	0.83
FL	SC	8	0.14	0.019-0.03	0	0.091	Chen, 1994
1991					7	0.0181
					14	0.0061
					0	1.0
					7	0.9
					14	0.02
TX	SC	9	0.14	0.044	0	1.51	Chen, 1994d
1992					7	0.29
CA	SC	7	0.14	0.042	0	0.41	Chen, 1994d
1993					7	0.14
					14	0.009
CA	SC	7	0.14	0.037	0	3	Dong, 1995c
1994					7	2.3
CA	WP	7	0.14	0.037	0	3.8	Dong, 1995c
1994					7	6.6
AZ	SC	7	0.14	0.05	0	3.5	Dong, 1995c
1994					7	3.2
AZ	WP	7	0.14	0.050	0	4.4	Dong, 1995c
1994					7	2.7

¹ Head without wrapper leaves

Table 28. Residues of tebufenozide in leaf lettuce, USA, 1991-1994.

State, year	Form.	Application			PHI, days	Residue, mg/kg	Reference
		No.	kg ai/ha	kg ai/hl
NJ	SC	7	0.14	0.043	0	3.5	Chen, 1994d
1991					7	2.2
CA	SC	8	0.14	0.042	0	5.7	Chen, 1994d
1991					6	1,7
PL	SC	8	0.14	0.019	0	0.88	Chen, 1994d
1991					7	0.41
rx	SC	9	0.14	0.044	0	2.7	Chen, 1994d
1991					7	0.69
CA	SC	7	0.14	0.025	0	3.7	Dong, 1995c
1994					7	1.1
CA	WP	7	0.14	0.025	0	3.5	Dong, 1995c
1994					7	2.5
AZ	SC	7	0.14	0.050	0	3.3	Dong, 1995c
1994					7	3.2
AZ	WP	7	0.14	0.05	0	3.6	Dong, 1995c
1994					7	2.6

Spinach. Five field trials on spinach were conducted at different locations in the USA. Plot sizes ranged from 0.31 to 2.4 ha (Chen et al., 1994d). Samples from three trials were analysed for RH-0897: all residues were below the LOD (0.01 mg/kg).

Other trials were carried out in the USA to compare the 2SC and 70WP formulations. Plot sizes ranged from 0.37 to 1.24 ha (Dong, 1995c). The residues of tebufenozide from treatments approximating proposed GAP ranged from 1 to 4.2 mg/kg.

Table 29. Residues of tebufenozide in spinach, USA, 1991-1994.

State, year	Form.	Application			PHI, days	Residue, mg/kg	Reference
		No.	kg ai/ha	kg ai/hl
VA	SC	6	0.14	0.05-0,058	0	10.3	Chen, 1994d
1991					7	7.1
AZ	SC	7	0,14	0.074-0.076	0	4.4	Chen, 1994d
1993					7	0.99
					14	0.13
CA	SC	8	0.14	0.075	0	5.5	Chen, 1994d
1991					7	8.1
OK	SC	7	0.14	0.050-0.052	0	5.1	Chen, 1994d
1993					7	1.3
TX	SC	9	0.14	0.044	0	15	Chen, 1994d
1992					7	2.7
CA	SC	7	0.14	0.025	0	7.0	Dong, 1995c
1994					7	3.9
CA	WP	7	0.14	0.025	0	6.95	Dong, 1995c
1994					7	3.3
TX	SC	7	0.14	0.05	0	8.3	Dong, 1995c
1994					7	3.8
TX)	WP	7	0.14	0.05	0	7.1	Dong, 1995c
1994					7	4.2