الفهرس 
Aphis craccivoraOnly 14 pages are availabe for public view
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Abstract
The present studies were carried out at the experimental farm of Toshka br Res. Station, Aswan Governorate during four faba bean growing seasons (2010-2011, 2011-2012, 2012-2013 and 2013-2014). br 5.1- Survey of arthropods associated with broad bean plants at Toshka br region Aswan Governorate. br Results indicated that the occurrence of 23 arthropod species is belonging br to 7 orders and one species of spider mite belonging to -#111;-#114;-#100;-#101;-#114; Acariforms. br Moreover, found 14 insect species natural enimes belonging to 7 orders. br -#102;-#114;-#111;-#109; surveyed arthropods, some insect and mite species were found to be br key pests and caused economic damages to faba bean plants these pests were br Pimelia angulosa, Liriomyza trifolii, Aphis craccivora and Tetranychus br urticae. br 5.2- Seasonal abundance, sowing dates of certain pests infesting faba br bean and associated their natural enemies. br This experiment was carried out during 2010-2011 and 2011-2012 br seasons at the experimental farm of Toshka Res. Station, Aswan br Governorate. The four faba bean varieties, namely, Roomy, Giza 40, Giza br 429 and Masr 1 were cultivated at (15 br th br Oct.), (30 br th br Oct.) and (14 br th br Nov.). br The considered insects were Aphis craccivora, Liriomyza trifolii, br Tetranychus urticae, Coccinella undecimpunctata, -#99;-#104;-#114;ysoperla carnea and br Pimelia angulosa. br 5.2.1- Aphis craccivora. br Results indicated that the population density of Aphis craccivora started br to appeared on faba bean plants at the third week of November, the br population then increased gradually with relatively high numbers during br third and fourth week of January and reached its maximum level of br abundance during fourth week of February. The population afterthat br decreased gradually to reach its lower level during the last week of March. br The obtained results indicated that the first growing season (2010-2011) br of the first sowing date (15 br th br Oct.) had the least total number of Aphis br craccivora compared with second growing season 2011-2012. The second br sowing date (30 br th br Oct.) of the second season 2011-2012 had the highest total br number of Aphis craccivora compared with the first growing season of br 2010-2011. The third sowing date (14 br th br Nov.) during the second season br 2011-2012 had the highest total number of Aphis craccivora compared with br the first growing season 2010-2011. Moreover, the total number of Aphis br craccivora in the third sowing date (14 br th br Nov.) was higher than that in the br first and the second sowing dates during the first and second growing br seasons of 2010-2011 and 2011-2012. It also, cleared that in the first and br second sowing date, the Aphis craccivora had two peaks through the two br growing seasons , in (1 br st br Feb.) and (3 br rd br Feb.) during two growing seasons of br 2010-2011 and 2011-2012, respectively. On the other hand in the third br sowing date Aphis craccivora had only two peaks (20 br th br Feb.) and (27 br th br Feb.) br in 2010-2011 and 2011-2012 seasons, respectively. Average numbers of br Aphis craccivora were fluctuated through the two growing seasons and br through the three sowing dates; this may be due mainly to the prevailing br weather factors. Results indicated that first sowing date was less infested by br Aphis craccivora than the second and third sowing dates on broad bean br plants. But the population density of Aphis craccivora in season 2011-2012 br was the higher than the population density in season 2010-2011. Also highly br significant differences in mean numbers of Aphis craccivora among the br tested varieties Roomy, G. 40, G. 429 and Masr 1, through three sowing br dates, highly significant differences in mean numbers of Aphis craccivora br between plant ages of plant through three sowing dates. br 5.2.2- Liriomyza trifolii. br Results indicated that the liriomyza trifolii on faba bean plants started to br appeared in November, then grow up gradually in December and January br and population density reached to maximum levelin February and Marach to br maximum level in February and March month. generally the population br density of Liriomyza trifolii with first season 2010-2011 on faba bean plants br were lower than the population at the second season of 2011-2012. In br addition, when comparing each growing season, individually, in the first br sowing date with the corresponding growing season in the second a nd third br date found that superiority of the second and third date in population density. br The population densities of this insect had differed level of abundance with br three studied sowing dates during two growing seasons. Results indicated br that in broad bean plants the rate of infestation with Liriomyza trifolii was br markedly influenced by sowing date and found that broad bean plants seeded br later (14 br th br Nov.) suffered heavier infestation than seeded earlier (15 br th br Oct.). br Also, highly significant differences in mean numbers of Liriomyza trifolii br between age of plant through three tested sowing dates. Results revealed that br the sowing dates, plant age and climatic factors are very important in br regulating the population dynamic of Liriomyza trifolii on broad bean plants. br 5.2.3- Tetranychus urticae. br Results revealed that Tetranychus urticae on broad bean plants started to br appeared in November with very low numbers, then grow up gradually in br December, January and February population density reach to maximum level br in March and April month. Results indicated that the population density of br Tetranychus urticae with second seasons 2011-2012 on broad bean plants br were higher than the population at the first season 2010-2011.