不同种植密度下的亚洲玉米螟自然种群生命表

The Life Table of the Natural Populations of Ostrinia furnacalis in Different Corn fileds With Various Planting Density Population

目的:探明不同玉米种植密度对亚洲玉米螟田间种群动态的影响。方法:于2016年在XX地区进行,选用耐密玉米品种良玉99,设置60 000、90 000株/hm^2两个处理,每处理3次重复,采用自然种群生命表调查方法,研究不同密度种植下玉米田亚洲玉米螟生命表。结果:高密度种植和常规密度种植田亚洲玉米螟的世代存活率无显著差异,一代均高于相应二代;两种密度的玉米田中,一代玉米螟的关键虫期均为1~3龄的蛀前幼虫,二代玉米螟的关键虫期均为卵期;一代亚洲玉米螟高密度种植田的天敌控制作用与常规密度田无显著差异;而二代玉米螟发生期间,天敌控制作用弱于常规种植田;高密度种植田一代亚洲玉米螟自然种群趋势指数Ⅰ为1.36,高于常规密度田(Ⅰ=1.06)。结论:高密度种植田更加有利于玉米螟种群数量的增长。

Objective: To get the relationship between the planting density of corns and the Ostrinia furnacalis′s population dynamics. Method: LIANGYU 99 was chosed to conduct this test. In the experiment, two density gradients were set 60000 and 90000 corns per hm^2, and each gradient had three plots. The life table technique was applied to analyzed different density gradient, results are as following. The survival rates of the Ostrinia furnacalis in the high and normal density fields were similar,the first generation were much higher than those in the second generation. Both high and normal density fields, the key insect period of the first generation of the corn borer were 1 ~ 3 age larvae before boring, the key insect period of the second generation of the corn borer were the egg stage. The predators control of the first generation between the high and normal planting density fields were similar; and the high density fields were higher than normal fields on the predators control effect of the second generation. The control function of natural enemies is significantly higher than normal planting field, especially cocoon bees and bacteria. The trend index(Ⅰ) for population increase of the first generation in high density fields was 1.36, higher than that in normal density fields(Ⅰ=1.06). Conclusion: High density planting was much suitable for the increment of the Ostrinia furnacalis population.