IMPACT OF GARLIC EXTRACT IN COMPARISON WITH CHLOROPYRIFOSE INSECTICIDE AGAINST CERTAIN PESTS AND ASSOCIATED PREDATORS IN COTTON FIELDS AT SHARKIA GOVERNORATE, EGYPT

Field experiments were conducted in cotton fields, Gossypium barbadense L. variety Giza 86 at Zagazig District, Sharkia Governorate, Egypt during 2014 season. Four programs were applied with three respective sprays for each using commercial formulation of garlic extract Nat-108  and varied as spray start times and interval periods towards the development of more environmentally sound technologies for management of cotton aphids (Aphis gossyppii), cotton thrips (Thrips tabaci), sweet potato whitefly (Bemesia tabaci), spider mites (Tetranychus spp.), leafhoppers (Empoasca spp.), green stink bug (Nezara viridula), pink bollworm (Pectinophora gossypiella) and cotton leafworm (Spodoptera littoralis). In addition to the side effects on several predators species found in cotton fields associated with cotton pests, such as, coccinellids, chrysopids, staphylinids, anthocorid, dipterous and true spiders were studied.  Results, educed that the commercial formulation of garlic extract at the rate of 1 litter/100 litter water showed relatively high efficiency against aphids, leafhoppers and thrips, with maximum reduction percentages of 81.33, 82.51 and 84.12%, respectively;  moderate efficiency against pink bollworm, whitefly, spider mites, green stink bug with maximum reduction percentages of  61.50, 78.89, 67.56 and 54.46%, respectively and low efficacy against predators except at the end season where the relatively highest reduction percentage was 62.91%, while it was less effective against the cotton leaf worm ranged 23.30-25.80% reduction in comparison with 70.56-90.00% reduction in cotton leafworm population for Dursban (chloropyrifose). So, the garlic extract cannot considered as a botanical pesticide against S. littoralis under cotton field conditions at Sharkia Governorate but needs more studies to evaluate its efficacy on different levels of S. littoralis infestation and stags. In regard to the programs results for garlic extract efficacy, it cleared that the first program tended to be the highest sustainable control of aphids, whitefly, thrips and spider mites on cotton plants, where the sprays started just after cotton plants emergence, whereas the numbers of pests were very low while the third program where the sprays started after 20 days of cotton plants emergence was tended to be the highest sustainable control of leafhoppers. In case of N. viridula, it could be decided that the organophosphorous pesticide, Dursban can be used as effective insecticide especially at the end season period. Finally, garlic extract was tended to be safe to predators especially throughout its effective activity period during the period from seedling to the end of growing season of cotton plants that confirmed by the results of the third program which ranged 2.57-21.46% reduction percentages in predators population. So, garlic extract could be recommended to be used effectively against cotton aphids, leafhoppers, cotton thrips and pink bollworm in IPM program of cotton pests in cotton fields. The organophosphorous compound, Dursban can be considered as good control pesticide against tested pests recorded reduction percentages ranged 56.99-96.99% but caused serious damage to associated predators on cotton plants at the end of season period recorded reduction percentages reached to 99.76% that disturbed the natural balance in cotton cultivation area environment.