Spatial Distribution Pattern and Sampling Technique of Larvae of a New Subterranean Pest of Licorice,Platy stoma sp.

Su Jia; Wang Guiping; Bao Fang; Song Zhongxing; Tang Zhishu; Tan Yao; Yu Yi

doi:10.14083/j.issn.1001-4942.2025.10.017

Abstract：In order to determine the spatial distribution of larvae of a newly discovered species of Platys-toma sp.in the underground root of licorice(Glycyrrhiza uralensis)and establish the theoretical sampling tech-nique,the damage of Platystoma sp.larvae to different planting years of licorice in field in this study,six ag-gregation indexes(C,Ca,I,m*,K,m*/m),Iwao's m*-m regression equation and Taylor's power law were used to analyze the spatial distribution pattern of Platystoma sp.larvae.The Iwao's theoretical sampling and sequential sampling technique were used to establish the sampling model and sampling number most suit-able for the field survey of Platystoma sp.larvae.The results showed that the damage rate of Platystoma sp.larvae to licorice in different planting years was 10.67％to 95.00％,and the average population density was 0.48 to 19.38 heads per square meter.The spatial pattern of Platystoma sp.larvae in the root of licorice field showed an obvious aggregation state,and the individuals attracted to each other;the aggregation of the popula-tion was caused by environmental conditions and aggregation tendency of the pests themselves.The theoretical sampling number model of Platystoma sp.larvae was established as N=[3.841 6(27.577/m+13.407)]/D2.When m0 was 2 heads per plant,the sequential sampling model was T(n)=2n±20.442√n.The theoretical sampling models of Platystoma sp.larvae under different population densities were further analyzed and put forward.These results could provide technical supports for scientific investigation and control of Platystoma sp.larvae,and provide theoretical guidance for prediction and field control of root maggot pests.