Different Tea Germplasms Distinctly Influence the Adaptability of Toxoptera aurantii (Hemiptera: Aphididae)

SIMPLE SUMMARY: The tea aphid, Toxoptera aurantii, is one of the most damaging pests of tea plants and substantially affects tea yield. Thus, understanding T. aurantii’s adaptability to various tea germplasms is critical for screening resistant materials. Here, we used EPG technology combined with an age-stage two-sex life table to assess T. aurantii’s adaptation to six tea germplasms. The findings revealed that various tea germplasms substantially impacted T. aurantii feeding behavior. Compared with other hosts, T. aurantii exhibited increased pathway activities and reduced phloem sap ingestion on ZK. Life table parameters indicated that the growth rate of T. aurantii was the slowest on ZK, and it also significantly affected the longevity and fecundity of T. aurantii. Thus, ZK was the least favorable host plant for T. aurantii population establishment among the six germplasms based on measurements of feeding behavior and population dynamics. ABSTRACT: Aphids are typical phloem-sucking insect pests. A good understanding regarding their feeding behavior and population dynamics are critical for evaluating host adaptation and screening of aphid-resistant resources. Herein, the adaptability of Toxoptera aurantii (Boyer) (Hemiptera: Aphididae) to different hosts was evaluated via electropenetrography and an age-stage, two-sex life table on six tea germplasms: Zikui (ZK), Zhongcha108 (ZC108), Zhongcha111 (ZC111), Qianmei419 (QM419), Meitan5 (MT5), and Fudingdabaicha (FD). Our findings revealed that the feeding activities of T. aurantii differed considerably among the host plants. T. aurantii exhibited significantly more pathway activities on ZK and FD than on the other hosts. However, the duration of feeding of T. aurantii on ZK phloem considerably decreased compared with those of the other germplasms. Life parameters indicated that T. aurantii exhibited the highest intrinsic rate of increase (r), net reproductive rate (R(0)), and finite rate of increase (λ) on MT5, and the maximum values of total longevity and oviposition period were recorded on FD; these variables were reduced significantly on ZK. The results of our study demonstrate that T. aurantii can successfully survive on the six tea germplasms; however, ZK was less suitable for T. aurantii and should be considered as a potential source of resistance in breeding and Integrated Pest Management.