الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The insect pests of sugar beet plants cause great economic losses. The present study has been performed to use IPM programs in the control of sugar beet insect pests. This study was carried out for two successive seasons (2015/2016 and 2016/2017) at the faculty of Agriculture, Kafer El-Sheikh University. The obtained results showed that the least susceptible varieties were Alauda, Maimouna and Clgogne to Spodoptera spp, Pegomyia mixta, Cassida vittata and Scrobipalpa ocellatella infestation (3.33, 3.50, 3.83), (3.17, 3.17, 3.00), (0.33, 0.33, 0.33) and (0.42, 0.5, 0.42) infested plants /10 plants, respectively, during season 2015/2016. Statistical analysis showed significant differences between the six tested sugar beet varieties. The number of Spodoptera spp larvae recorded the maximum in the first plantation (220 larvae/180 plants). While the largest numbers of P. mixta, S. ocellatella, C. vittata, Aphis and Leaf hoppers occused in the third plantation (340 larvae/180 plants), (231 larvae/180 plants), (421 larvae and adults/180 plants), (151 nymphs and adults/180 plants), respectively during season 2016/2017. By releasing the predator chrysoperla carnea larvae, data showed a reduction in Aphids, C. vittata, S. ocellatella, leaf hoppers and P. mixta numbers in the two successive seasons with overall mean of reduction (80.29, 67.44, 72.64, 58.5, 49.83%) (81.84, 59.27, 66.93, 60.58, 40.9%) of Aphis spp, larvae of C. vittata, larvae of S. ocellatella, nymphs of leaf hoppers, larvae of P. mixta, respectively. Concerning intercropping sugar beet plants with faba bean plants, data had a significant effect in reducing Spodoptera spp, P. mixta, C. vittata, S. ocellatelal numbers in the first season 2015/2016 (the total number of infested plants 7, 16, 13, 16 plants, respectively) and in the second season 2016/2017 (6, 13, 8, 18 plants, respectively), also caused increasing the number of the studied natural enemies which were (True spiders, Coccinellidae, Paederus alfierii, C. carnea, Formicidae, Opius nitidulator, Monorthocheata nigra, Syrphus corolla, Orius spp) in the two seasons. The lowest percentage of infested plants was recorded in the treatment with foliar fertilization by micronutrients during the two seasons. There were recorded (20%, 20%, 30%, 20%), (10%, 20%, 20%, 20%) of Spodoptera spp, P. mixta, C. vittata and S. ocellatella, respectively. The presence of chard and some flowering weeds in sugar beet field (around borders or between fields) encourage the parasitism by O. nitidulator on P. mixta larvae, the total percentage of parasitism was 55.73% in season 2015/2016. The maximum overall mean of reduction in Spodoptera spp and C. vittata larvae number caused by alternative insecticides were (78.59% and79.71%, respectively) in the first season 2015/2016 and (81.74% and 71.55%, respectively) in the second season 2016/2017 compared to conventional insecticide (85.61% and 96.26%, respectively) in 2015/2016 season and (92.12% and 97.67%.respectively) in 2016/2017 season. As for the natural enemies associated with Spodoptera spp (Formicidae, C.carnea, True spiders) and C. vittata (Coccinellidae), the maximum overall mean of reduction were (60.74, 57.38, 53.19 and 57.17%, respectively) in the first season 2015/2016 and (70.05, 63.29, 68.32 and 73.2%, respectively) in the second season 2016/2017 compared to conventional insecticide (79.59, 79.86, 66.67 and 83.56%, respectively) in season 2015/2016 and (96.7, 88.98, 84.04 and 89.73%, respectively) in 2016/2017 season. The previous results indicated the role of some control methods that have been studied in reducing the number of sugar beet insect pests and preserving natural enemies compared to conventional insecticides.