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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 ρ 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 .

In order to reasonably protect and utilize natural enemies for comprehensive control of Frankliniella intonsa, a systematic investigation was conducted on F. intonsa and natural enemies in tea gardens in Hefei, Anhui Province, and the spatial following effect of natural enemies on F. intonsa was studied. The semi-variogram of natural enemies and thrips was obtained by the geostatistics method, and the correlation degree between them was analyzed by the grey correlation degree analysis method. The higher the correlation degree between natural enemies and F. intonsa, the closer the relationship between natural enemies and F. intonsa was. In this study, we analyzed the relationship between 11 natural enemies of F. intonsa in tea gardens from October 28, 2020 to November 20, 2020 and from August 22, 2021 to November 19, 2021. The top five natural enemies with the largest closeness index to F. intonsa in Huangshan Dayezhong tea garden are Oxyopes sertatus, Theridion octomaculatum, Plexippus setipes, Xysticus ephippiafus and Erigonidium graminicolum. The top five natural enemies with the largest closeness index to F. intonsa in Pingyang Tezao tea garden are Erigonidium graminicolum, Plexippus setipes, Xysticus ephippiafus, Oxyopes sertatus and Clubiona japonicola. Among the top five natural enemies in the two tea gardens, those in common are Oxyopes sertatus, Erigonidium graminicolum, Xysticus ephippiafus and Plexippus setipes. According to the summation of the closeness index and the sum of the serial numbers, the top five natural enemies closely related to the spatial following of F. intonsa in the tea gardens were Oxyopes sertatus, Plexippus setipes, Erigonidium graminicolum, Xysticus ephippiafus and Theridion octomaculatum. One of the factors closely related to the space of F. intonsa in the same tea garden was the ratio of F. intonsa to a certain natural enemy. The smaller the ratio was, the closer the following relationship was. The results of this study provide scientific basis for biological control and natural enemy protection of F. intonsa.

Our aim was to study the close relationship between the number of Empoasca onukii and its natural enemies in tea plantations to provide a scientific basis for the control of E. onukii. The relationship between the number of E. onukii and its main natural enemies in tea plantations in Hefei, China, were compared by gray relational analysis, and then the relationships between seven meteorological factors and the populations of E. onukii were analyzed by the method of path analysis. The results showed that among the top six natural enemies most closely related to the population of E. onukii, two natural enemies were the same in the three years of study and four natural enemies were the same in any two years of the study, and that the natural enemy species closely related to the population of E. onukii varied greatly among years. The direct effect of monthly average relative humidity was the greatest effect in 2020 and the direct effect of monthly average temperature was the greatest effect in 2021, with both being negative in terms of their effect on the population size of E. onukii. The direct effect of the number of days of rainfall was the greatest effect in both 2021 and 2022, and the indirect effect of monthly sunshine hours through rainfall days was the greatest effect on the population of E. onukii. The highest temperatures in early and mid-August 2022 were higher than in previous years, which had an impact on the growth and development of subsequent E. onukii.

This paper aims to analyse how to effectively protect and scientifically utilize the natural enemies of Pentatomidae in tea plantations in the peak period. In this paper, the spatial, quantitative and temporal relationships between Pentatomidae and its natural enemies in “Pingyangtezao”, “Wuniuzao”, “Huangshandayezhong”, “Anjibaicha”,”Longjing 43″ and “Nongkangzao” tea gardens in Hefei, China were comprehensively compared and analyzed with the methods of geostatistical analysis, gray system analysis and temporal ecotone overlap index analysis. According to the size of the closeness index, the top three natural enemies with the largest sum of spatial, quantitative, and temporal closeness indexes in the six tea gardens were Clubiona japonicola (X7, 16.514), Oxyopes sertatus (X5, 16.390) and Xysticus ephippiafus (X2, 16.270). The size of the ratio between the number of Pentatomidae individuals and natural enemies largely determines whether the natural enemies follow Pentatomidae pests closely or not. The better the growth of tea plantations and the richer the diversity of pest species, the more accurately the predation preference of natural enemies can be reflected. In the control of Pentatomidae, specific analysis should be made according to the occurrence characteristics of target pests in different tea plantations and the basic attributes of tea plantations (species, growth, population characteristics of natural enemies and pests, etc.) in order to scientifically utilize its natural enemies.