Effect of temperature and soil moisture on the efficacy of indigenous and imported strains of the entomopathogenic nematode, Heterorhabditis sp. against the black cutworm, Agrotis ipsilon (Hufnagel) (Lepidoptera/Noctuidae)

Egyptian Journal of Biological Pest Control

Table 1 Mortality percentages of Agrotis ipsilon (4th and 6th larval instars and 3-day-old pupae) at different concentrations of Heterorhabditis strains TAN5 and Hb₈₈ at temperature 20, 25, and 30 ± 2°C and water content in the soil 20%

Con. IJs/cm² of soil surface	% Mortality of Agrotis ipsilon
	Heterorhabditis strains TAN5			Heterorhabditis strains Hb₈₈
	4th instar larvae	6th instar larvae	3-day-old pupae	4th instar larvae	6th instar larvae	3-day-old pupae
20 ± 2 °C
30	6	4	2	8	6	4
60	24	20	14	26	24	20
120	48	36	26	56	38	34
240	62	54	38	68	54	50
480	80	68	52	84	72	64
Average	44	36.4	26.4	48.4	38.8	34.4
F-value*	0.6114			0.3525
25 ± 2 °C
30	24	20	16	18	16	14
60	44	40	32	38	34	30
120	62	60	54	60	56	52
240	80	80	74	78	76	70
480	100	100	94	100	96	90
Average	62	60	54	58.8	55.6	51.2
F-value*	0.0907			0.0732
30 ± 2 °C
30	16	14	10	14	12	10
60	36	34	28	34	32	26
120	58	52	46	56	50	44
240	82	78	64	76	72	62
480	100	96	82	100	92	80
Average	58.4	54.8	46	56	51.6	44.4
F-value*	0.2007			0.1761

*Statistical analysis confirmed that the mortality rate between 4th, 6th larval instars and pupae for each of the treated EPN was non-significant