南京裂爪螨种群消长及其空间格局时序动态

THE POPULATION GROWTH AND DECLINE OF SPIDER MITE SCHIZOTETRANYCHUS NANJINGENSIS MA ET YUAN AND TIME DYNAMIC OF ITS SPATIAL PATTERN

通过一年的林间定点抽样调查与研究 ,结果表明 :(1)南京裂爪螨 (Schizotetranychus nanjingensis Maet Yuan)卵和活动螨 (幼、若、成螨 )群体的旬数量消长规律较为相近 ,卵的数量高峰期为 3月上、中旬和 9月上旬到 10月上旬 ;活动螨群体的数量高峰期为 3月上、中、下旬和 9月上旬到 10月下旬。 4月上旬到 7月上旬 ,卵和活动螨群体数量处于较低的水平。 (2 )天敌捕食螨与南京裂爪螨卵和活动螨群体在数量上的相关性分别达到显著 (r=0 .4 72 8)和极显著 (r=0 .5 830 )水平 ,可见 ,捕食螨对该螨种群在时间维上的控制效应强 ,且对活动螨的控制效应比卵强。 (3)南京裂爪螨卵的空间格局在年周期中均呈聚集分布 ,呈现高度聚集 -低度聚集 -中度聚集 -低度聚集的变化规律 ;活动螨群体的空间格局在年周期中大多数时期均呈聚集分布 ,仅 6月中旬呈均匀分布 ,表现为中度聚集 -低度聚集 -均匀分布 -中度聚集 -高度聚集 -低度聚集的变化规律。这些现象与该螨不同群体本身的生物学特性和生存环境的变化有关。 (4)相关分析表明 :气象因子和天敌捕食螨对卵聚集程度的影响大小序列为旬平均气温 >旬降雨量 >旬平均相对湿度 >天敌捕食螨 ,对活动螨群体聚集程度的影响序列为天敌捕食螨 >旬平均相对湿度 >旬降雨量 >旬平均气温。

By spot check in Phyllostachys heterocycla cv. pubescens forest in Xiqin, Nanping, Fujian province in 1997, the research results showed that (1) the amount growth and decline regularity of spider mite's (Schizotetranychus nanjingensis Ma et Yuan) egg in a year was similar with active mite's (The active mite include larva, nympha and adult of the spider mite). The amount of egg reached the highest level in the first ten days to second ten days of March, and Sep to the first ten days of Oct, so did the active mite in March and Sep to Oct. The amount of egg and active mites all kept low level from April to July. (2)The correlativity between eggs, adults and their natural predatory mites reached prominent (r=0.4728) and great prominent level (r=0.5830) respectively, so the predatory mites' control efficiency to the mites was prominent. But the efficiency to active mites was more prominent than to eggs. (3) The eggs' spatial patterns of each stage in a year were all of aggregation distributions, which presented the regularity of high degree aggregation low degree aggregation mid degree aggregation low degree aggregation. Active mites' spatial patterns of each stage in a year were all of aggregation distributions except of average distribution in June, which presented the regularity of mid degree aggregation low degree aggregation average distribution high degree aggregation low degree aggregation. These regularities were related to the spider mite's biological characteristics and their living surroundings. (4)The correlative analysis indicated that the effect sequence of climate and predatory mites on eggs' aggregative degree was air temperature>rainfall>relative humidity>predatory mites, and on the active mites' aggregative degree, the sequence was predatory mites>relative humidity>rainfall>air temperature.