Table 6 Progeny production of Sitophilus zeamais in maize treated with binary mixtures from Plectranthus glandulosus leaf powder with Hymenocardia acida wood ash under fluctuating laboratory conditions (temp. = 22.76 ± 2.02 °C; r.h. = 69.87 ± 9.93%)

Mean number of F ₁ adult progeny

0

42.50 ± 1.71^aA

42.50 ± 1.17^aA

42.20 ± 1.17^aA

–

5

14.25 ± 0.85^bB

23.00 ± 2.86^bAB

28.50 ± 4.65^abA

5.05*

10

9.25 ± 1.65^bcB

15.75 ± 1.65^bcAB

23.75 ± 3.79^bA

7.97*

20

4.75 ± 1.44^cdB

8.25 ± 0.63^cdAB

14.50 ± 3.80^bcA

4.34*

40

2.00 ± 0.82 ^dB

7.00 ± 0.82^dAB

8.00 ± 1.08^cA

12.40*

F _{(4; 15)}

145.94***

70.41***

16.23***

Inhibition of adult emergence relative to control (%)

0

0.00 ± 0.00^dA

0.00 ± 0.00^dA

0.00 ± 0.00^dA

–

5

66.51 ± 1.23^cA

45.92 ± 6.42^cAB

33.27 ± 10.56^cB

5.47*

10

78.32 ± 3.87^bA

62.88 ± 3.97^bAB

44.53 ± 8.27^bcB

8.66*

20

88.91 ± 3.47^abA

80.42 ± 2.05^aAB

66.60 ± 7.45^aB

5.31*

40

95.49 ± 1.74^aA

83.39 ± 2.32^aB

80.92 ± 3.17^aB

9.88*

F _{(4; 15)}

233.90***

86.76***

19.96***

EC₅₀ (95%FL) g/kg

2.553(1.291; 3.764)

5.567(3.540; 7.390)

10.694(6.741; 15.088)