SEASONAL ABUNDANCE OF THREE PIERCING-SUCKING INSECTS AND THEIR ASSOCIATED NATURAL ENEMIES ON COTTON PLANTS IN THREE DIFFERENT SOWING DATES IN ELGHARBIA GOVERNORATE, EGYPT.

Abstract

The present study focused on the seasonal abundance of varioussucking pests observed on cotton plants in relation to their associatednatural enemies at three different sowing dates to determine the bestsowing date could escape from the infestation at Gemmeiza AgriculturalResearch Station, El-Gharbia Governorate during 2006- 2007 cottonseasons. This study clarify that there are three piercing-sucking speciesinfesting cotton plants. Theses species are cotton whitefly, Bemisia tabaci(Genn.), cotton leaves Jassid, Emboasca lybica (Deg.) and cotton aphid,Aphis gossypii Glover. The associated natural enemies were lady birdCoccinella undecimpunctata (L.) & C. septempunctata (L.), Scymnusinterruptus (Goeze.) & S. syriacus (Marseu), rove beetle, Paederusalfierii (Koch); Orius albidiennis (Reuter), O. laevigatus (Fiebern),Green lacewing, Chryso/la carnea (Steph.) and true spiders. From thisstudy it could be concluded that the first sowing date was the suitable onefor cultivating cotton plants which the suitable date for predator'sactivation (build up) and resultant in piercing-sucking pest's reductionespecially A. gossypii. However, the obtained results are of greatimportance for the sowing date recommendation to improve and develop the crop management program in cotton fields