Some Ecological Aspects of some Piercing-Sucking Pests Infestation on Four Vegetable Marrow Varieties in Relation to their Histological Features and their Control and Evaluation of Yield

Abstract

Two field experiments were conducted during 2020 at the Plant Protection Research Station at Qaha, Qalubiya Governorate. Those included fluctuation in population growth rate of Bemisia tabaci, Aphis gossypii, Thrips tabaciand Tetranychus urticaein addition to evaluation of the susceptibility degree of 4vegetable marrow varieties (hybrid Aziad, hybrid Marseille, Askandrany and Amna)to infestation by previously mentioned pests. The study also included the application of lemon oil, ginger oil, fenugreek oil, green tea oil and egyxide plus(water soluble natural oil)for control of these each of pests. The 5oils (at 500 and 1000ml.)were mixed with 250gm hivit 80%WDG. Also, 5insecticides; Vapcomic 1.8%EC, Mobet, Trivap 75%WP, Oecos 3.2%EC and Hivit 80%were assayed at the recommended concentrations.Aziad variety could be fairly categorized as the highest susceptible(S)to infestation with the above mentioned pests of vegetable marrow plants, with means 31.61, 19.45, 1.76 and 2.31/leaf to B. tabaci, A. gossypii, T. tabaciand T. urticae, respectively/leaf.Obtained data indicated that A. gossypii recorded the highest growth rate 6.77, taking time difference 7days at Marseille variety. As for the anatomical measurements, those were the highest in case of Amna variety and the lowest in Aziad variety. Also, highest fruit yield was that of Amna variety and lowest in Aziad variety.The obtained records exhibited, that vapcomic and fenugreek oil+Hivit(1000ml+250gm)caused the significantly highest reduction against B. tabaci and A. gossypii counts on Aziad variety, as the recorded average of their reductions after 14days of first and second spray were(88.8 and 88.1%),(93.2 and 91.3%)and(96.2 and 95.2%), respectively.