2种经营方式下早竹林虫瘿的空间分布研究

Spatial Distribution of Phyllostachys praecox Gall under Two Management Patterns

早竹（Phyllostachys praecox C.D.Chu et C.S.Chao）别名早园竹（浙江德清）,属禾本科（Gramineae）刚竹属（Phyllostachys Sieb.et Zucc）刚竹组（Sect.Phyllostachys）,产于我国江苏、安徽、浙江、江西、湖南、福建等省[1-3]。早竹因其笋期早、产量高、笋味美,而成为我国南方的重要笋用竹种[1]。据统计,我国南方早竹的种植面积在6.7万hm2以上,年产值达10亿多元[4]。然而,随着早竹大面积的推广种植和新的生产经营方式的推广应用,早竹遭受造瘿昆虫的严重危害。

[Objective]The objective of the study is to clarify the characteristics of spatial distribution of Phyllostachys praecox gall under two management patterns. [Methods]Five aggregated indices and an aggregated formula were used to describe the spatial distribution patterns of Ph. praecox gall. The gall distribution under two different management patterns were compared. Through regression analysis,the relationship between the third-level shoots and the number of galls was determined. [Results]Statistical model analysis showed that the gall spatial distribution followed an uniformly aggregated pattern,and the basic components of gall was colony. The reasons for aggregation were the aggregation and characteristics of bamboo gall-makers. On the bamboo plant,significant difference was found in gall density among three layers of bamboo canopy. In rough management plots,the galls were concentrated in the middle layer of the canopy,the height is 3- 4 m and 4- 5 m sections. In intensively managed plots,the galls were concentrated in the upper layer of the canopy,the height is 2- 3m section. In two different management patterns,there is a significant linear regression relation between the number of gall and the nunmber of third-level shoots. [Conclusion]Thespatial distribution of Ph. praecox gall followed an aggregated distribution pattern. There are significant differences in gall density among different heights of bamboo canopy. Management patterns will affect the distribution of gall,while obtruncation will affect the nunmber of third-level shoots. The nunmber of third-level shoots are related to the number of gall.