Maximum adverse effect was observed at highest concentration wher

Maximum adverse effect was observed at highest concentration where no adult emergence occurred. Also, adults emerged at lower concentrations were small in size with varied abnormalities. Xiong et al. [33] found that out of 40 isolates from marine micro-organisms, Streptomyces sp.173, similar to avermectin B1 possessed strong insecticidal potential against H. armigera. In another study, Xiong et al. [34] reported strong inhibitory activity of Streptomyces avermitilis strain 173 isolated from marine source against

Heliothis zea (Boddie), Plutella xylostella (Linnaeus), Spodoptera exigua (Hübner) and aphids. Table 3 Effect of ethyl acetate extract of S. hydrogenans and azadirachtin on mortality rate of different developmental stages of S.litura Treatments Concentrations (μg/ml) Larval mortality (%) Prepupal find more mortality (%) Pupal mortality (%) Corrected Pupal mortality (%)   Control – - 13.80 ± 0.67a – Streptomyces ethyl acetate extract 400 – - 48.26 ± 1.01b 39.98 ± 1.40a 800 20.00 ± 00.00a 20.00 ± 4.47a 57.13 ± 2.09c 50.26 ± 0.45b 1600 70.00 ± 12.40b 66.66 ± 0.38b 100.00 ± 00d 100.00 ± 0.00c f- value 16.30** 107.79** 863.97** 1436.26** R2 0.80 0.81 0.94 0.94 Azadirachtin 400 76.66 ± 1.59c – 85.70 ± 1.22e 83.41 ± 0.45d 800 96.66 ± 0.42d – - – 1600 100.00 ± 00e – - – f- value 146.19** – - – R2 0.85 – - – Mean ± SE followed by different letters with in a column are significantly different. Tukey’s test P ≤ 0.05, R2 = Coefficient of determination, **Significant

at 1% level. Figure 1 Effect of ethyl acetate extract of S. hydrogenans on % age emergence of S.litura. Columns and bars represent the mean ± SE. Different letters above the columns representing PF-02341066 solubility dmso each concentration indicate significant differences at Tukey’s test P ≤ 0.05. Adult survival time was also influenced by the S. hydrogenans as longevity of emerged adults declined significantly from 11.50 days in control to 4.33 days at 800 μg/ml (P ≤ 0.01) (Table 4). Fecundity in emerged adults

from treated larvae was also significantly selleck chemical inhibited. It declined from 1500 eggs/female (control) to 150.20 eggs/female at 400 μg/ml concentration (P ≤ 0.01). The viability of these eggs was also negatively affected as the eggs failed to hatch whereas in control 87.66% hatching of eggs was observed (Table 4). No egg laying was recorded at 800 μg/ml concentration. Abouelghar et al. [35] also demonstrated the negative effects of sublethal concentrations of spinosad on development, fecundity and food utilization in the BAY 57-1293 mw cotton leafworm, S. littoralis (Boisd.). Table 4 Effect of ethyl acetate extract S. hydrogenans on longevity, fecundity and percent hatching of S.litura adults Concentrations (μg/ml) Longevity (in days) (Mean ± S.E.) Fecundity (No. of eggs laid/ female) (Mean ± S.E.) Percent Hatching (Mean ± S.E.) Control 11.50 ± 0.76a 1500 ± 151.00a 87.66 ± 0.91 400 5.00 ± 0.77b 150.20 ± 22.40b – 800 4.33 ± 0.66b – - 1600 – - – f- value 28.89** 78.64** – R2 0.91 0.67 0.

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