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本文引用Iwao及Taylor等方法,研究了黄地老虎越冬幼虫在苜蓿田埂上的空间分布型。研究表明属均匀分布(α=-0.6256<0、β=1.9048>1),但在样方内的分布却是聚集的(b=1.7975>1)。这种分布是黄地老虎幼虫习性及其栖境所造成的。根据空间分布信息,计算出越冬幼虫调查所需样方面积为3.5—5平方米,比原规定的可少调查1.5—5平方米。黄地老虎(Agrotis segetum Schiff.)是新疆墨玉地区农作物的头号害虫。该虫多以老熟幼虫在苜蓿田埂中越冬,并以为害春播作物为最严重。当地主要依据调查越冬后的虫口密度,发出春季黄地老虎发生程度的中、长期予报。为了提高调查及予测的准确性,更好地指导防治,1981年我们对黄地老虎越冬幼虫的空间分布型及抽样调查作了初步研究,现将结果整理如下,供讨论。
This paper quoted Iwao and Taylor et al. Studied the spatial distribution patterns of overwintering larvae in the field of alfalfa yellow tiger. Studies have shown that the distribution is uniform (α = -0.6256 <0, β = 1.9048> 1), but the distribution in the sample is aggregated (b = 1.7975> 1). This distribution is caused by the habitat of yellow tiger larvae. According to the spatial distribution information, we calculated that the sample area of overwintering larvae survey is 3.5-5 square meters, less than the original survey of 1.5-5 square meters. Agrotis segetum Schiff. Is the number one crop of pests in Moyu area, Xinjiang. Most of the insects in the alfalfa larvae mature larvae wintering, and to harm the spring sowing crops for the most serious. Based mainly on the investigation of the density of pests after winter, the local issue of mid-and long-term reports of the occurrence of spring yellow tigers. In order to improve the accuracy of investigation and prediction, and to better guide prevention and treatment, in 1981 we conducted a preliminary study on the spatial distribution patterns of overwintering larvae of the Yellow Landrace and sampling surveys. The results are summarized below for discussion.