Data from: Experimental evolution to increase the efficacy of the entomopathogenic fungus Beauveria bassiana against malaria mosquitoes: effects on mycelial growth and virulence

Entomopathogenic fungi such as Beauveria bassiana are currently considered as a potential control agent for malaria mosquitoes. The success of such strategies depends among others on the efficacy of the fungus to kill its hosts. As B. bassiana can use various resources for growth and reproduction, increasing the dependency on mosquitoes as a nutritional source may be instrumental for reaching this goal. Passage of entomopathogenic fungi through an insect host has been shown to increase its virulence. We evaluated the virulence, fungal outgrowth, mycelial growth rate, and sporulation rate of two B. bassiana isolates (Bb1520 and Bb8028) that underwent 10 consecutive selection cycles through malaria mosquitoes (Anopheles coluzzii) using an experimental evolution approach. This cycling resulted in an altered capacity of evolved B. Bassiana lineages to grow on different substrates while maintaining the ability to kill insects. Notably, however, there were no significant changes in virulence or speed of outgrowth when comparing the evolved lineages against their un-evolved ancestors. These results suggest that fungal growth and sporulation evolved through successive and exclusive use of an insect host as a nutritional resource. We discuss the results in the light of biocontrol and provide suggestions to increase fungal virulence.球孢白僵菌（Beauveria bassiana）等昆虫病原真菌（Entomopathogenic fungi）目前被视为防控传疟按蚊的潜在生物制剂。此类防控策略的成败，除其他影响因素外，取决于真菌杀灭宿主的效能。球孢白僵菌可利用多种资源完成生长与繁殖，因此增强其对蚊虫营养来源的依赖性，或对实现该防控目标具有关键作用。已有研究证实，昆虫病原真菌经昆虫宿主传代后，其毒力会得到提升。本研究采用实验进化（experimental evolution）方法，对两株球孢白僵菌分离株（Bb1520与Bb8028）开展连续10轮以科卢兹按蚊（Anopheles coluzzii）为宿主的传代筛选，并评估了进化菌株的毒力、真菌增殖能力、菌丝生长速率及产孢率。 传代筛选使进化后的球孢白僵菌谱系在不同营养底物上的生长能力发生改变，但仍保留了杀虫活性。值得注意的是，相较于未进化的原始亲本菌株，进化后的谱系在毒力与增殖速度上均未出现显著差异。上述结果表明，通过连续且仅以昆虫宿主作为营养来源的传代培养，可使真菌的生长与产孢能力发生适应性进化。本文结合生物防治（biocontrol）的研究背景对上述结果展开讨论，并提出了提升真菌毒力的可行策略。