三种玉米蚜虫种群的生态位分析

对重庆市郊区1998～1999年春玉米上3种蚜虫种群的数量动态、生态位宽度和生态位重叠进行了系统的分析研究．结果表明，发生在春玉米上的玉米蚜(Rhopalosiphum maidis)，禾谷缢管蚜(Rhopalosiphum padi)和麦长管蚜(Sitobion avenae)3种蚜虫混合种群的种群数量消长呈现出5月中下旬和6月下旬两个高峰；在生态位宽度上，Livens生态位宽度指数(Bi)分析表明，麦长管蚜表现出时间上的高度分化，玉米蚜表现出空间上的高度聚集特性，而禾谷缢管蚜的分化并不明显；在生态位重叠上，玉米蚜和禾谷缢管蚜的HturlbeIt生态位重叠指数(Lij)最高，玉米蚜和麦长管蚜次之，禾谷缢管蚜和麦长管蚜最小．在春玉米上发生的3种蚜虫中，玉米蚜具有较强的竞争优势．

Niches analysis of three aphid populations on spring sowing maize

Systematic analysis of aphid populations and niches patterns on spring sowing maize was carried out during 1998 ~ 1999 in the suburbs of Chongqing. The results indicated that there were three aphid populations Rhopalosi-phum maidis Fitch. , Rhopalosiphum padi Linn, and Sitobion avenae Fahricius distributed on the spring sowing maize. The mixed aphid populations traded off during the growth period of spring sowing maize, and two peaks of quantitative counts were shown at the mid and last ten days of May and the last ten days of June. In addition, the niches of aphid population were also discussed from one dimension (i.e., temporal or spatial) to two dimensions (i.e., temporal and spatial). Through the quantitative analysis of niche breadth and niche overlap, the highly temporal differentiation of M. avenae and the highly gathering character of R. maidis were all indicated . R. padi showed an indistinct differentiation, while R. maidi was a dominated population on the spring sowing maize.