الفهرس 
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Abstract
Phaseolus vulgaris L. are considered the most important vegetables plants. It infested with many pests cause considerable damage in the crop under Egyptian conditions.
The present study was carried throughout two successive seasons 2011 & 2012 on two varieties 1st var. Nebraska (common dry bean) and 2nd var. Bronco (green bean) at Qalubiya governorate. Survey the pests infesting two varieties and investigation indicated that, eleven insect pest species, one mite specie and ten natural enemies (parasite and predator) were recorded. The population dynamics of key pests infesting two varieties of green bean showed that, the seasonal abundance of the pests were higher during 2012 than 2011 (2306.18 & 1885.9 individual pest / 120 leaflets for two successive respectively). On the other hand the population densities of the pests were higher abundant on autumn plantation than these recorded on spring plantation (2388.5 & 1802 individual pest/ 120 leaflets, respectively). During spring plantation on var. Bronco (in the first season 2011) Tetranychus urticae was the most dominant pest followed by Bemisia tabaci then Liriomyza trifolii in the 3rd group. In the second season 2012 1st group was T. urticae, 2nd group was L. trifolii and 3rd group was B. tabaci the number of generations for each pest was recorded during this plantation. According to spring plantation on var. Nebraska data indicated that, these pests could be divided into 4 groups as follows 1st group was T. urticae, 2nd group was L. trifolii, 3rd group B. tabaci and the last group contains on Aphis carccivora, Empoasca dispenis and Thrips tabaci. Also, numbers of generations for each pest were recorded. During autumn plantation on var. Bronco, B. tabaci was the most dominant pest. These pests could be divided into 5th group: 1st B. tabaci, 2nd T. urticae, 3rd L. trifolii, 4th Ophiomyia phasoeli (which appeared only during autumn plantation) 5th group contains
the other 3 pest (Aphis carccivora, Empoasca dispenis and Thrips tabaci. The numbers of generation were recorded. According to autumn plantation on var. Nebraska, B. tabaci was the most dangerous pest. : followed with L. trifolii then T. urticae and O. phasoeli in the same group the other pest namely; A. carccivora, E. dispenis and T. tabaci came in the last group with least populations. The seasonal fluctuation of the investigated pests in relation to certain weekly mean of the weather factors (maximum temperature, minimum temperature, mean relative humidity (R.H%) as abiotic factors in addition to age plant Orius albidipennis, Coccinella undecimpunctata, Phytoseiulus macropils and the parasite Opius dissitus as biotic factors were tested and discussed to clarify their simultaneous effects on the population dynamics of the pests infesting Bronco and Nebraska varieties during two successive seasons 2011&2012. The efficiency of different chemical compound included Agromec gold 1.8 EC, Actellic 50%EC, Achook 0.15, KZ OIL 95% EC and KZ OIL + Match in reducing the population densities of green bean pests was assayed. According to general mean percentage of reduction in population of main green bean pests (Bemisia tabaci nymph, Liriomyza trifolii larvae, Ophiomyia phasoeli larvae and Tetranychus urticae, it is clear that KZ oil + Match (79.82%) was the most potent one followed by KZ oil 95% E.C. (73.14%), Agromic gold 1.8 E.C. (68.46%), Achook 0.15% (64.34%) and Actellic 50% E.C (62.62%) was the least potent one. According to interaction between of intercropping system and agricultural ecosystems on the rate of infestation with certain green bean pests, it is clear that, plastic greenhouse harbored the highest number of pests infesting green bean plants, Open field had the least number of pests infesting the same vegetable crop while scaffold net greenhouse came intermediate. Spraying with basil oil is the best method to reduction the number of pests attacking green bean irrespective of intercropping with basil plants or cultivating under plastic or scaffold net greenhouse. The relationship between population density of B. tabaci and crop yield of green bean was negative and highly significant whereas ”r” values were -0.79 and -0.91, while ”b” values were -0.20 Kg and -0.24 Kg during two successive
seasons 2011&2012, respectively. The same trend was accrued with L. trifolii whereas ”r” values were -0.84 and -0.75, while ”b” values were -0.11 Kg and -0.10 Kg. Statistical analysis showed that the relationship between population of O. phasoeli which appeared only during (autumn plantation) was negative significant whereas ”r” values were -0.86 and -0.84, while ”b” values were -0.22 Kg and -0.28 Kg. The same trend was obtained with Tetranychus urticae urticae whereas ”r” values were -0.95 and -0.93, and ”b” values were -0.28 Kg & -0.26 Kg. According to the unit effect of infestation with single pest on the crop yield of green bean showed that one individual of B. tabaci, L. trifolii, O. phasoelia and T. urticae caused reduction percentages of (1.31% & 1.57%), (0.73% & 0.65%), (1.46% & 1.83%) and (1.86% & 1.70%) in crop yield of green bean during 2011&2012, respectively. i.e. about 1.45%, 0.69%, 1.64% and 1.78% in average. Estimation of economic levels of infestation showed that when population density of Bemisia tabaci less than 8 nymph/30leaflets could be regarded as General Equilibrium position, when population ranged between 8 to 13.38 nymphs/30leaflets could be regards as Economic Threshold Level, when population density ranged between 38 to 49 nymphs/ 30leaflets could be regard as Economic Injury Level, when population density increased as regard between 73.6 to 96.26 / 30 leaflets could be regards as Economic Damage Level. According to Liriomyza trifolii, when population density less than 12 larvae /30leaflets could be regarded as General Equilibrium position, when population regard between 23.6 to 27 larvae/30leaflets could be regards as Economic Threshold Level, when population density ranged between 46.8 to 49 larvae / 30leaflets could be regard as Economic Injury Level, when population density increased as regard between 81.9 to 90 larvae / 30 leaflets could be regards as Economic Damage Level. For Ophiomyia phasoeli, when population density less than 3 larvae and pupa /30leaflets could be regarded as General Equilibrium position, when population regard between 17.18 to 18 larvae and pupa /30leaflets could be regards as Economic Threshold Level, when population density ranged between 31.36 to 44 larvae and pupa / 30leaflets could be regard as
Economic Injury Level, when population density increased as regard between 63.09 to 90 larvae and pupa / 30 leaflets could be regards as Economic Damage Level. For Tetranychus urticae, when population density less than one movable stage /30leaflets could be regarded as General Equilibrium position, when population regard between 1.7 to 2 movable stage /30leaflets could be regards as Economic Threshold Level, when population density ranged between 43.8 to 48.9 movable stage / 30leaflets could be regard as Economic Injury Level, when population density increased as regard between 47.73 to 49.8 movable stage / 30 leaflets could be regards as Economic Damage Level.
Key Words: Phaseolus vulgaris L., green bean, common dry bean, Bemisia tabaci, Tetranychus urticae, Liriomyza trifolii, Aphis carccivora, Empoasca decipiens and Thrips tabaci, weather factors, predator, Orius albidipennis, Coccinella undecimpunctata, Phytoseiulus macropils, Opius dissitus, chemical compound, intercropping, agricultural ecosystems, basil plants, greenhouse, Estimation of economic levels, General Equilibrium position, Economic Threshold Level, Economic Injury Level and Economic Damage Level.