Occurrence dynamic and spatial distribution pattern of Echinocnemus squameus Billberg adults in dry land high-quality rice field

【Objective】To clarify the occurrence dynamics，spatial distribution patterns and population sampling techniques of Echinocnemus squameus Billberg adults in dry land high-quality rice fields，and to provide scientific reference for investigation，sampling，prediction and comprehensive control of E. squameus in high-quality rice fields in dry land. 【Method】In the dry land high-quality rice planting areas of Haozhiba Village，Haguoma Village and Nuoguo village in Zhutang Township，Lancang County，Pu’er City，Yunnan Province，the dynamic and spatial distribution patterns of adult E. squameus were investigated by continuous field survey in 2022 and 2023. The spatial distribution patterns and aggrega-tion reasons of E. squameus were analyzed by using the clustering index method，Iwao regression analysis method，Taylor power function method and population aggregation mean. Based on the spatial distribution results，theoretical sampling model and sequential sampling model were formed.【Result】In 2022 and 2023，the occurrence dynamics of E. squameus adults were unimodal in dry land high-quality rice field of investigation sites，which started in mid-May and occurred sporadically after mid-August. The peak occurred in July and reached its peak in mid-to-late July. The clustering index method，Iwao regression analysis and Taylor power function method analysis showed that in 2022 and 2023，E. squameus adults in the dry land high-quality rice fields of the three investigation sites were clustered in the fields，which was caused by the living habits of the insects and environmental factors such as climate，soil moisture and plant growth. In 2023，the theoretical sampling models based on spatial distribution of adult E. squameus in Haozhiba Village and Nuoguo Village were N=\fract^2D^2\left(\frac2.170m+0.214\right) and N=\fract^2D^2\left(\frac2.599m+0.228\right)respectively，and the sequential sampling models based on critical control indicators of E. squameus adult were T₀（n）=2n±2.279 n、T₀（n）=2n±2.472√n respectively.【Conclusion】The occurrence dynamic of E. squameus adult in Zhutang Township，Lancang County，Pu’er City，Yunnan Province is single-peak type. E. squameus adults are clustered in the field，which is caused by their living habits，climate， soil moisture and plant growth.