الفهرس 
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Abstract
Field experiments were conducted at the Experimental Farm of Sakha Agricultural Research Station during 2014/2015 and 2015/2016 sugar beet seasons for the following objectives: 1) Evaluate the toxicity of some insecticides to certain sugar beet insects (Pegomyia mixta, Aphids, Cassida vittata, Scrobipalpa ocellatella, Nezara viridula and Spodoptera littoralis) and their associated insect predators (Paederus alfierii, chrysoperla carnea and Coccinellidae) and spiders. 2) Investigate the effect of some insecticides on root and sugar yield. Sampling was carried out by direct count (visual record) of insects and predators numbers in the field. Samples were taken just before spraying and 1, 3, 7 and 10 days after spraying. Roots were weighed in the field after harvest to calculate the root yield per feddan, and sugar content (%) was determined by using sucrometer device in laboratory of Sugar Crops Research Department (Sakha) to estimate the sugar yield per feddan.. The obtained results could be summarized as follows: 1) the results show that the alternative insecticides were efficient in reducing the larvae numbers of sugar beet insects and in the same time, caused a low reduction on predators in comparison with the conventional ones. 2) These results show that the insecticides play an important role in reducing insect pest numbers, consequently in raising the productivity of sugar beet crop.