Effects of picorna-like virus on the feeding habits and reproduction of the citrus red mite and its control factor

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K22308
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 39:Agricultural and environmental biology and related fields
• Research Institution: Kyoto University
• Principal Investigator: Osakabe Masahiro 京都大学, 農学研究科, 准教授 (50346037)
• Project Period (FY): 2019-06-28 – 2022-03-31
• Keywords: ピコルナ様ウイルス / ミカンハダニ / 紫外線 / 寄主植物

Outline of Final Research Achievements

Genome sequence of a single strand RNA virus detected from the citrus red mite (Panonychus citri) was determined, and the effects of host plant of mite and ultraviolet radiation on increase / decrease of the virus were tested. The genome sequencing indicates that this virus is the same species as or closely related to Hubei picorna-like virus 79 strain. This virus increased inside the spider mite when the mites fed on citrus leaves while it was significantly decreased by UV-B irradiation on the mites. However, cost for survival and reproduction of spider mites due to increase of the virus was not detected, so that this virus was likely symbiotic.

Free Research Field

応用昆虫学

Academic Significance and Societal Importance of the Research Achievements

昆虫では30種以上のピコルナ様ウイルスが報告されているが、生態的役割は多くが未解明である。一方、毒性を持つ植物と植食者の関係は、植物の化学的防御と植食者の適応を通じた共進化の文脈で考えられる。しかし、昆虫ウイルスの中には宿主の行動を制御するものも知られており、共生的ウイルスが寄主の食性に影響することが分かれば食性分化の新たなメカニズムが提案できる。また、ウイルスが宿主の繁殖に影響を及ぼし、太陽光紫外線がその増殖の抑制を通じて宿主の繁殖を助ける場合、紫外線の新たな生態的役割を提示できる。したがって、今後さらなる研究の進展が望まれる。