Comparative Effect of Some Bio Insecticides with Chlorpyrifos on Cotton Leafworm

Document Type : Original Article

Authors

Plant Protection Res. Institute, ARC, Giza,Egypt

Abstract

The efficiency of Chlorypyrifos, Jojoba and Diplel DF against 2nd and 4thinstars of the laboratory strain of Spodoptera littoralis was evaluated under laboratory conditions Chlorypyrifos was the most toxic compound against the 2nd and 4th larval instars of Spodoptera littoralis. All the treated larvae were biologically affected by the three tested compounds. The effect was varied according to the larval instars and tested compounds. Therefore, the treated larvae have resulted in decreased pupation and adult emergence percentages, and the 2nd instar treated with Chlorypyrifos had the strongest effect in this respect. The treatment of 2nd instar with the three compounds induced the highest increase in larval, pupal duration and adult emergence percentages.
           Hence, the larval treatment of 2nd and 4th instars with Chlorypyrifos and Diplel DF gave the shortest period of adult longevity, as compared to control. The larval treatment of 2nd and 4th instars with the three tested compounds increased the adult emergence, the treatment of 2nd instar with Chlorypyrifos and 4th instar with Diplel DF had the strongest effect in this respect.

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