THE TOXIC ACTION OF CERTAIN BOTANICAL EXTRACTS TO VEGETABLE SUCKING PESTS IN EGYPT.

Master of Science, University of Ain Shams, Faculty of Agriculture, Department of Plant Protection, 1996 by Ehab Mostafa Bakr

Abstract:

The present study was mainly devoted to elucidate the biological activity of certain botanical substances against red spider mite Tetranychus urticae and black bean aphid Aphis fabae. The solvent extracts of Bitter apple seeds Citrullus colocythis and seeds of Jew s mallow Corchorus obitorius, Banana leaves juice Musa paradisica and American aloe leaves juice Agava americana and ready made mixture of camphor and olive oil (1: 9 ) were undertaken in this study.

Hexane and acetone were the best solvent to extract or elute chemical compounds have acaricidal and aphicidal action from Bitter apple and Jew s mallow seeds, respectively.

According to toxicity against red spider mite, the investigated botanical materials could be arranged as follows; Bitter apple seed hexane extract, Jew s mallow seed acetone extract, camphor/olive (1: 9 ) mixture and crude American aloe juice. Against aphid, the botanical materials order were camphor/olive oil (1 :9 ) mixture, Bitter apple seed hexane extract and Jew s mallow seeds acetone. extract.

Bitter apple seed hexane extract proved to be the best repellent material to red spider mite followed by camphor/olive oil (1: 9 ) mixture and Jew s mallow seeds acetone extract, while the tested extracts gave poor repellency effect to black bean aphid and this order was Jew s mallow seed acetone extract, camphor/olive (1: 9 ) mixture and Bitter apple seeds hexane extract.

Ultra violet (25420A) had no/or slight influence on Bitter apple seed extract and camphor/olive mixture and Jew s mallow seeds extract.

Camphor/olive oil mixture was more effective than Bitter apple seed extract against both of red spider mite and black bean aphid under open and protective semifleld condition. Both of the previous tested materials were more effective against both of pests under protective than open semifield condition.

Camphor/olive mixture proved to be more effective in reducing the population of mites and aphid on pepper plants at plastic house cultivation.