摘要
在采用蝗虫微孢子虫Ｎｏｓｅｍａｌｏｃｕｓｔａｅ防治过的草场中进行抽样调查，研究了草原蝗虫优势种类、混合种群平均密度与蝗虫微孢子虫疾病分布之关系，以及该疾病的空间分布。在防治后的当年，蝗虫微孢子虫疾病的感染率随着混合种群平均密度及靶标蝗虫亚洲小车蝗Ｏｅｄａｌｅｕｓａｓｉａｔｉｃｕｓ的感病率的下降而降低。但是，次靶标蝗虫如宽须蚁蝗Ｍｙｒｍｅｌｅｏｔｅｔｉｘｐａｌｐａｌｉｓ（一种中后期发生的种类）其感病率呈上升趋势，表明该疾病可在不同发生期种类蝗虫之间进行有效地传播。病蝗虫在防治后第７ｄ其空间分布呈随机分布（Ｐｏｉｓｏｎ），第２８ｄ则是聚集分布，第４０ｄ时也呈聚集分布。于１９９３年、１９９４年对１９８８年（样区Ⅱ）、１９８９年（样区Ⅲ）采用微孢子虫防治过的草场进行抽样调查。结果表明，在二个样区中，二年混合种群平均虫口密度与混合种群的平均感病率呈正相关（相关系数分别为ｒ＝０２８９，ｒ＝０４７９）。蝗虫微孢子虫病在主要优势种，如亚洲小车蝗、宽须蚁蝗、白边痂蝗Ｂｒｙｏｄｅｍａｌｕｃｔｕｏｓｕｍｌｕｃｔｕｏｓｕｍ、皱膝蝗Ａｎｇａｒａｃｒｉｓｓｐｐ．、毛足棒角蝗Ｄａｓｙｈｉｐｐｕｓｂａｒｂｉｐｅｓ均有分布。二个样区中?
The rate of infection of Nosema locustae decreased with the decrease of densities of the complex population of rangeland grasshoppers in the treated season(as Plot 1). However, the rate of infection of N. locustae in Myrmeleotettix palpalis, one of the dominant species of grasshoppers occurred lately in the season, increased with its increase in number in the complex population. The spatial distribution of infected grasshoppers by N. locustae in the treated season, varied with sampling time.On the 7th days after treatment with N. locustae bait (7 5×10 9 spores/1 5 kg wheat bran/ha), the spatial distributions fixed to the Poisson distribution. But on the 28th and 40th days fixed to aggregate distributions. The densities of complex grasshoppers population were correlated with the percentages of infection of N. locustae in August of 1993 and August of 1994 in the plots, where were treated with N. locustae in 1988 and 1989 respectively (as Plot 2 and Plot 3). Further analysis of the data from the plots showed that both densities and infections in 1993 were significantly higher than that in 1994. And N. locustae still distributed widely in most of dominant species of grasshoppers, Oedaleus asiaticus, M. palpalis, Bryodema luctuosum luctuosum, Angaracris spp. and Dasyhippus barbipes. The spatial distribution of infected grasshoppers by N. locustae both in 1993 and 1994 were suitable to Poisson distribution in Plot 1 and Plot 2. The dispersal distance and directions of N. locustae were investigated in 1993 and 1994 in the two plots too. The results indicated that the dispersal distance of N. locustae was at least 1000 meters, and the dispersal direction might be affected by the geographic features and the prevalent wind etc.
出处
《昆虫学报》
CAS
CSCD
北大核心
1998年第S1期119-127,共9页
Acta Entomologica Sinica
基金
国家自然科学基金
关键词
草原蝗虫
蝗虫微孢子虫
分布与扩散
感病率
grassland grasshoppers, Nosema locustae, spatial distribution, dispersal pattern
