Studies On Natural Population Life Table Of Alfalfa Weevil, Hypera Postica (Cyllenhal)

This study on fertility indicated that every alfalfa weevil generation female laid eggs mete trend "M". In three generations alfalfa weevil's female, over-winter generation's adult's survival time, Spawning experience time, spawning total quantity and spawning peak duration were all higher than first generation, second generation obviously.The functional model of predation in C. septempunctata to different stages of Alfalfa Weevil lavae as below:To 3rd larvae, the formula of Holling model is 1/Na=0.0844+0.7143×1/N,and sudden attack rate "a" is 1.4000,threatment time range "Th" is 0.084 4d, daily max quantity of prey "Namax" is 11.84; To 4th age lavae, the-the formula of Holling model is 1/Na=0.1541+0.3657×1/N,and sudden attack rate "a" is 2.743,threatment time range "Th" is 0.154 ld,daily max quantity of prey "Namax" is 6.49.The functional model of predation in Misumenoides aleatorius to different stages of Alfalfa Weevil larvae as below:To 3rd larvae, the formula of Holling model is 1/Na=0.1129+0.5719×1/N,and sudden attack rate "a" is 1.7486,threatment time range"Th" is 0.1129d,daily max quantity of prey "Namax" is 8.86; To 4th age lavae, the the formula of Holling model is 1/Na=0.1249+0.5121×1/N,and sudden attack rate "a " is 1.953,threatment time range "Th" is 0.124 9d,daily max quantity of prey "Namax" is 8.01.After the experiment confirmed that there were four species parasitical natural enemies could parasitic in alfalfa weevil larvae and pupa in the alfalfa field in Hutubi County of Xinjiang, it was significant differences that alfalfa Tetrastichus incertus parasitism. There were the same synchronism between parasitism changes and alfalfa weevil changes.The alfalfa weevil natural population life table in Xinjiang was made. Price analysis of the survey curve showed that the magnitude of alfalfa weevil population was decreased in forepart stage, from egg to second stage. The 1st generation of Alfalfa Weevil's englacial rate of increase was 0.069 6, finite rate of increase was 1.077 2, IPC(index population control)was 7.38. The each adult female produces 547.71 granular eggs. The magnitudes of alfalfa weevil population were rose for 4.080. The 2nd generation's englacial rate of increase was 0.021 3, finite rate of increase was 1.019 6, IPC(index population control)was 2.31. The each adult female produces 250.21 granular eggs. The magnitudes of alfalfa weevil population were rose for 2.344.