Evaluation of the close degree of the spatial relationship between natural enemies of tea gardens and Frankliniella intonsa based on variance analysis of cluster samples

The aim of this paper is to clarify the difference of spatial closeness between natural enemies and Frankliniella intonsa, and to provide a scientific basis for rational protection and utilization of natural enemies. This paper applied the block-sample square difference analysis method, Gray correlation degree method, the aggregation intensity index method and rho$$ \rho $$ index method to study the difference in the closeness of the spatial relationship between F. intonsa and natural enemies when the number of F. intonsa and their natural enemies was the highest and the minimum area occupied by F. intonsa individuals and colonies in five tea plantations in Hefei, Anhui province in 2021 and four tea plantations in 2020. The results were as follows: 1) Tetragnatha squamata Karsch, Xysticus ephippiafus, Erigonidium graminicolum and Theridion Octomaculatum were the top four natural enemies closely related to F. intonsa in 2021. The top three natural enemies closely related to F. intonsa in 2020 were Tetragnatha squamata Karsch, Xysticus ephippiafus and Theridion Octomaculatum. Two years ago, Tetragnatha squamata Karsch and Xysticus ephippiafus were the same. 2) Cluster size did not change the distribution patterns of natural enemies and F. intonsa. 3) The aggregation of F. intonsa was caused by their own causes or some environmental factors, and the aggregation of natural enemies was caused by environmental factors. 4) In 2021, the minimum area occupied by individuals and groups of F. intonsa in tea gardens was 2m(2), and in 2020, it was 8 m(2).