松实小卷蛾松梢螟对松树的为害性和空间格局的研究

对松实小卷蛾、松梢螟的为害性和空间格局及在序贯抽样技术中的应用的研究结果表明,二虫对松树为害具有选择性,松实小卷蛾幼虫主要为害侧枝,为害程度火炬松>黑松>湿地松>马尾松,松梢螟为害则以主梢为主,为害程度 黑松>湿地松>马尾松>火炬松.松实小卷蛾和松梢螟的空间格局分别为负二项分布和奈曼分布,松实小卷蛾明显超过防治指标,急待全面防治,松梢螟低于防治指标,可不防治.

Spatial distribution petrova cristata Dioryctria rubella Spatial distribution patterns in petrova cristata, Dioryctria rubella and their habits of infestation

Spatial distribution patterns in petrova cristata, Dioryctria rubella and their habits of infestation/Xie Ke* et al//Journal of Jiangsu Forestry Science & technology.-1990, 17(2) .-30~35 The spatial distribution patterns, sampling methods, and their habits of damage were investigated in Xuyi county, Jiangsu, in 1989.Frequency tests showed that p.cristata and D.rubella can fit the negative binomial and Neyman distribution, respectively.P. cristata's emergence number is over the management index and needs to control thoroughly.D.rubella's occurrence number is lower than that of control, and need not to control. Tow insect speciece that the habits of infestation to shoots of four pines have their selectivity. P. cristata mainly infest the laternal branch , its damage level is pinus taeda P. thunbergii P.elliottii P .massoniana.Hawe-ver, D. rubella mainly infest the main branch, its injured degree is P, thunbergii P.elliottii P .massoniana P .taeda. *Authors/ address: Forestry research institute of Jiangsu province, Dongshanqiao, Zhonghuamenwie, Nanjing 211153, PRC