INSEctiCIDAL EFFICIENCY OF SOME CHEMICAL COMPOUNDS ON THE WHITEFL Y, Bemisle tabaci (Gennad.) INFESTING COTTON PLANTS AND ITS ASSOCIATED NATURAL ENEMIES

Several problems in contrOlling pests as well as pollution have been risen
from the intensive use of insecticides. Therefore, this work was carried out at Sakha
Agricultural Research Station during 2001 cotton growing season to evaluate the
initial and residual effect of two chitin synthesis inhibitors (diafenthiuron and
buprofezin), one conventional insecticides (Triazophos), two dinitromethelin derivative
(Confidor and Best) and one insect growth regulator (Thiamethoxam) against cotton
whitefly Bemisia tabaci (adult and immature stage) and their associated natural
enemies summarized results showed the following:
Confidor and Best induced the highest initial reduction giving 84.2 and
82.7% respectively against immature stage of the white ny, the rest of tested
compound were ranged from (75.4 to 77.3 % reductlon). Where Buprofezin and
Confidor induced the highest residual activity on Immature stage of whitefly, (73.77
and 72.9% reduction). For the effect on the mature stages Confidor and Best induced
the highest initial and residual activity giving 81.8 and 80.6% and 71.5 and 67.5%,
respectively. The other tested compounds caused initial activity ranged between
(64.7 to 75.5% reduction), while they caused residual activity ranged between (47.6
to 61.8% reduction).
As for the side effect on the associated natural enemies, all tested
compounds had no effect on ali tested enemies (true spiders, Coccinella
undecimpunctats, Chrysoperia camea and Peederus a/fierit).