Zhang Meng-Di, Wu Sheng-Yong, Yan Jun-Jie, Reitz Stuart, Gao Yu-Lin
State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.
Department of Crop and Soil Sciences, Malheur Experiment Station, Oregon State University, Ontario, OR, USA.
Insect Sci. 2023 Feb;30(1):197-207. doi: 10.1111/1744-7917.13049. Epub 2022 May 24.
The potato tuber moth, Phthorimaea operculella, is the most damaging potato pest in the world and is difficult to control as the larvae are internal feeders in the foliage and tubers. Entomopathogenic fungi that colonize plants as endophytes have lethal and sublethal pathological effects on insect pests. We show that Beauveria bassiana colonizes the aerial parts of potato plants endophytically after inoculation through soil drenching. Endophytic B. bassiana persisted in potato foliage for more than 50 days postinoculation. Bioassays indicated that foliage of B. bassiana-inoculated potato plants were pathogenic against larvae of P. operculella. Sublethal experiments indicated that B. bassiana negatively affected the growth, development, and reproduction of P. operculella. Development experiments showed that the weight of P. operculella pupae reared on B. bassiana-colonized potato plants (4.25 mg) was significantly less than that of those reared on uninoculated control plants (8.89 mg). Compared with newly eclosed larvae fed on control plants, those fed on B. bassiana-inoculated plants had significantly lower survivorship, with only 17.8% developing to the adult stage. Oviposition of P. operculella females reared on B. bassiana endophytically colonized plants was significantly lower (35 eggs/female) than of those reared on uninoculated plants (115 eggs/female). This study demonstrates that endophytic B. bassiana can be a potential biological control agent for the control and management of P. operculella. Comparing pupal weights of P. operculella reared on potato plants inoculated with the B. bassiana strain GZGY-1-3 and on untreated control plants, pupae from the control plants were significantly heavier than those from treated plants.
马铃薯块茎蛾（Phthorimaea operculella）是世界上对马铃薯危害最大的害虫，由于其幼虫在叶片和块茎内部取食，因此难以防治。作为内生菌定殖在植物体内的昆虫病原真菌对害虫具有致死和亚致死病理效应。我们发现，球孢白僵菌通过土壤浇灌接种后可内生定殖在马铃薯植株的地上部分。接种后，内生球孢白僵菌在马铃薯叶片中持续存在超过50天。生物测定表明，接种球孢白僵菌的马铃薯植株叶片对马铃薯块茎蛾幼虫具有致病性。亚致死实验表明，球孢白僵菌对马铃薯块茎蛾的生长、发育和繁殖有负面影响。发育实验表明，在球孢白僵菌定殖的马铃薯植株上饲养的马铃薯块茎蛾蛹重（4.25毫克）显著低于未接种对照植株上饲养的蛹重（8.89毫克）。与取食对照植株的新羽化幼虫相比，取食接种球孢白僵菌植株的幼虫存活率显著较低，只有17.8%发育到成虫阶段。在球孢白僵菌内生定殖的植株上饲养的马铃薯块茎蛾雌虫产卵量（35粒/雌虫）显著低于未接种植株上饲养的雌虫（115粒/雌虫）。本研究表明，内生球孢白僵菌可能是一种用于防治和管理马铃薯块茎蛾的潜在生物防治剂。比较在接种球孢白僵菌菌株GZGY-1-3的马铃薯植株和未处理对照植株上饲养的马铃薯块茎蛾蛹重，对照植株的蛹显著重于处理植株的蛹。
