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The two-spotted spider mite Tetranychus urticae is considered to be one of the. most economically important pests, since it infests over 200 species of plants (Johnson 1991). Beauveria bassiana is highly control agent to this mite, and affects its mortality biochemistry and physiolology. To test this effect the B. bassiana was applied at 105 spores / ml using dipping leaf - disc treatment method. Mortality, total proteins, carbohydrates and lipids of mite were measured; Mites adult females were susceptible to B. bassiana, with high mortality rate recorded. The effect of B. bassiana on proteins level in the mycosed extract homogenate appeared, decreasing than the non-mycosed during the period of experiment. The means of total protiens are 225,220 and 183 µg/ml after 24,48 and 72hrs respectively, compared with 327 µg/1000 individuals in untreated control. Effect of the B. bassiana on the level .of the carbohydrates decreased in the treated extract homogenate than the untreated one during the period of experiment. The mean of total carbohydrates at 24,48 and 72 hrs after treatment were 142,138 and 115 µg/ml respectively, compared with149 µg/1000 ml, In untreated control. The effect of B. bassiana on lipids level in treated extract homogenate appeared decreasing than in untreated one during the period of experiment. The obtained result refer to the mean total lipids were 92,77, and 70 µg/ml after 24,48 and 72 hrs, respectively compared with 88 µg/1000 individuals untreated adult females of T. urticae. This study improves that entomopathogenic fungus B. bassiana causes many biochemical and physiological changes in the mite Tetranychus urticae. B. bassiana is also considered as a safe biological control agent to the environment. [ABSTRACT FROM AUTHOR]

The present investigation was carried out at the experimental farm of Agricultural Research Centre, Giza Governorate, Egypt throughout two successive seasons (2010 and 2011) on chicory plants. Obtained results clearly indicated the following: 1) Twenty seven species of insects and mites were surveyed on Chicory plants during the two successive growing seasons. 2) Eight insects and mites considered important pests. 3) The spider mite Tetranychus urticae Koch proved to be the most abundant species during the two growing seasons showing the highest population density general mean recording 26. 47, 15.60 movable stages/sample in the two seasons, respectively. The lowest density was obtained with the phytophagous mite Bryobia sp. 4) Six insect pests their population density general means were intermediate, these insects were the aphid Uroleucon ambrosiae (Thomas), the white fly B. tabaci (Genn.), Thrips tabaci Lind., the potato leaf hopper Empoasca decipiens (Paoli), the sugar cane mealy bug Saccharicoccus sacchari (Cockerell) and the sugar beet fly Pegomyia mixta (Will) during two seasons. [ABSTRACT FROM AUTHOR]