摘要： Studies in tobacco fields were conducted in 1993.The results showed that the distribution pattern of the larva was aggregative,and the aggregation did not change with the densities of population of the larva.The characteristics of the vertical distribution of the larva on tobacco plants was more in the lower leaves than in the upper.The difference of population density among the tobacco fields with an elevation of 490 meters and 900 meters was not significant.The number of sampling was given under different precisions by using two-stage sampling technique.
关键词:
Phthorimaea operculella ( Zeller ),
spatial distribution,
two-stage sampling,
elevation,
leaf area loss
马继盛, 杨效文, 徐广, 赵世民, 董金川, 李三立. Spatial distribution and sampling of larvae of Phthorimaea operculella(Zeller) and its harmfulness[J]. 华北农学报, 1994, 9(S2): 61-66. doi: 10.7668/hbnxb.1994.S2.013.
Ma Jisheng, Yang Xiaowen, Xu Guang, Zhao Shimin, Dong Jinchuan, Li Sanli. [J]. ACTA AGRICULTURAE BOREALI-SINICA, 1994, 9(S2): 61-66. doi: 10.7668/hbnxb.1994.S2.013.