Biological characteristics and efficacy of Bacillus thuringiensis var. thuringiensis against the cotton leaf roller, Syllepte derogata (Fabricius, 1775) (Lepidoptera: Crambidae)

Egyptian Journal of Biological Pest Control

Table 1 Effects of Bacillus thuringiensis var. thuringiensis against Syllepte derogata larvae under laboratory conditions

*Btt* concentration (g/l)	Mortality of 2nd instar (%)		T test	Mortality of 4th instar (%)		T test
*Btt* concentration (g/l)	3rd day	7th day	T test	3rd day	7th day	T test
0.3 g/l	40.00 Ba*	50.00 Ca	t = 1.22	13.33 ABa	16.66 BCa	t = 0.71
0.3 g/l	40.00 Ba*	50.00 Ca	P = 0.28	13.33 ABa	16.66 BCa	P = 0.52
0.4 g/l	56.67 Ba	66.67 Ba	t = 2.12	23.33 Aa	30.00 ABa	t = 1.00
0.4 g/l	56.67 Ba	66.67 Ba	P = 0.10	23.33 Aa	30.00 ABa	P = 0.39
0.5 g/l	93.33 Aa	100.00 Aa	t = 2.00	30.00 Aa	36.66 Aa	t = 1.00
0.5 g/l	93.33 Aa	100.00 Aa	P = 0.18	30.00 Aa	36.66 Aa	P = 0.39
Control	0.00 C	0.00 D		0.00 B	0.00 C
ANOVA	F = 107.9333	F = 156.2500		F = 12.2667	F = 18.8667
ANOVA	P = 0.0001	P = 0.0001		P = 0.0023	P = 0.0005

*There is no significant difference (99% probability level) between the same capital letters shown in the same column in terms of Btt concentrations (P = 0.01)
**There is no significant difference (99% probability level) between the same lowercase letters shown in the same line in terms of the effect of the same concentration on the same larval period (P = 0.01)