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Empoasca onukii Matsuda is an important pest widely distributed in tea areas in China, which greatly affects tea production and quality. The long-term use of chemical control measures will cause environmental pollution. To better utilize wandering spiders that have strong competitive effects on the predation of E. onukii, we conducted a path analysis between the populations of E. onukii and wandering spiders in 3 tea plantations in 2020 and 2021. The wandering spider species that had the greatest direct and indirect effects on the population of E. onukii were analyzed by the magnitude of the path coefficient. Then, a gray system analysis was conducted to determine the closeness of the populations of different wandering spiders to E. onukii by the magnitude of gray correlation coefficient. Finally, the competition coefficients were calculated to determine the competitiveness of wandering spiders. In addition, considering the influence of the number of E. onukii on the interspecific competition of wandering spiders, the gray correlation coefficient and competition coefficient were combined to derive the competition intensity index, which was used to analyze the competitiveness of wandering spiders in a comprehensive manner. The highest competition coefficients in 2020 and 2021 were found for Ebrechtella tricuspidata Fabricius (Araneae: Thomisidae) (X2, 0.5329) and Clubiona reichlini Fabricius (Araneae: Clubionidae) (X4, 0.8475), respectively. The magnitude of the competition intensity index showed that the most competitive wandering spider in 2020 and 2021 was E. tricuspidata (X2, 0.5692) and C. reichlini (X4, 0.8892), respectively. The least competitive spider in both years was Plexippus setipes Karsch (Araneae: Salticidae) (X7). The more competitive the wandering spider is, the closer it is to E. onukii in terms of numbers, and the more dominant it is in feeding on E. onukii. By reasonably protecting and utilizing the competitive E. tricuspidata (X2) and C. reichlini (X4), we can achieve sustainable and effective control of E. onukii. [ABSTRACT FROM AUTHOR]

In order to clarify the dominant species and natural enemies of Ceroplastes rubens Maskell, and in order to provide scientific basis for the comprehensive management of Ceroplastes rubens Maskell in tea gardens, the quantiy, temporal and spatial relationships of eight main pests and Ceroplastes rubens Maskell in Dabie Mountain Area, Qianshan, China were analyzed by angle cosine coefficient, niche analysis method and geostatistical method to evaluate the dominant natural enemies. Using the sum of closeness index to judge the natural enemies of dominant species of Ceroplastes rubens Maskell, in low-altitude tea gardens, the top four natural enemies closely related to the number, Tetragnatha maxillosa(1.0000), Erigonidium graminicolum(0.9936), Theridion octomaculatum(0.9253) and Enoplognatha japonica(0.8832). In low-altitude tea gardens, the first four natural enemies closely related to the time, T. maxillosa(1.0000), E. japonica(0.9830), Harmonia axyridis(0.9038) and E. graminicolum(0.8925). In low-altitude tea gardens, the first four natural enemies closely related to the space, E. graminicolum(1.0000), T. octomaculatum(0.9794), Neoscona theisi(0.9794) and Misumenops tricuspidatus(0.9632).The results showed, in low-altitude tea gardens, the top four natural enemies closely related to Ceroplastes rubens Maskell in number, time and space, T. maxillosa (2.9462), E. graminicolum (2.8861), E. japonica (2.7238) and T. octomaculatum (2.6972).In low-altitude tea gardens, whether was related closely to Ceroplastes rubens Maskell in quantity, time, space was relevant to the ratio of the sum quantity of Ceroplastes rubens Maskell to the sum quantity of natural enemies at the peak (June 6, June 22, July 13). Smaller the ratio, that was, the preys of natural enemies were less, then closer was the relationship between preys and natural enemies. In middle-altitude tea gardens, the top four natural enemies closely related to the number, T. maxillosa(1.0000), E. japonica(0.7889), E. graminicolum((0.6913) and Clubiona reichini((0.6769). In middle-altitude tea gardens, the top four natural enemies closely related to the space, T. maxillosa(1.0000), C. reichini(0.8933), N. theisi(0.8093) and E. japonica(0.7997).The results showed, in the middle altitude tea gardens, the top four natural enemies closely related to Ceroplastes rubens Maskell in number and space, T. maxillosa(2.0000), E. japonica(1.5886), C. reichini(1.5702) and N. theisi(1.4463).The top four natural enemies of the two altitudes that are closely related to Ceroplastes rubens Maskell are T. maxillosa and E. japonica.The results provide a reference for the biological control, rational protection and utilization of natural enemies of Ceroplastes rubens Maskell. [ABSTRACT FROM AUTHOR]

Honey bees (Apis cerana Fabricius) were collected from 195 colonies at seven different localities spanning the main beekeeping areas in Huangshan. Morphometric methods were used to measure seven standard morphometric characters, and these bees were compared to samples from the Henan, Shandong, and Yunnan provinces. Principal component analysis of the total Huangshan database yielded two clusters: bees from Jinxian and Jixixian, and those from other localities. Within the latter cluster, discriminant and hierarchical cluster analyses revealed overlapping regional sub-clusters: bees from Huangshanqu, Qimenxian, Huizhouqu, and Shexian, and those from Yixian. Significant differences between the means of the three clusters were demonstrated using Wilks' lambda statistic. Morphocluster separation was related to altitude differences. Moreover, we noted some regions with high intercolonial variance, suggesting introgression among these defined honeybee populations. [ABSTRACT FROM AUTHOR]

In 2002 to approximately 2004, an investigation was made on the bee population dynamics and its relationships with the ecological environment in four ecological regions of Anhui Province. The results indicated that in the mountainous areas of south and west Anhui, there were 46 and 37 species of nectariferous plants, and the distribution density of Apis cerena cerena population was 2.01 and 1.95 colony x km(-2), respectively. In Jianghuai area and Huaibei plain, there were 17 and 12 species of nectariferous plants, which had concentrated and short flowering period and fitted for Apis mellifera Ligustica oysterring and producing, and the distribution density of Apis cerena cerena population was 0. 06 and 0. 02 colony x km(-2), respectively. Bee population fluctuation and distribution was affected by wasp predation. The breeding proportion of Apis cerena cerena to local apis population was 41.5%, 36.8%, 3.1% and 1.1%, and that of Apis mellifera Ligustica was 58.5%, 63.2%, 96.9% and 98.9% in the mountainous areas of south and west Anhui, Jianghuai area, and Huaibei plain, respectively.