Blastospores are yeast-like infective cells to arthropod pests and can be obtained shortly by liquid culture. However, fungal isolates exhibit striking variation in production, desiccation tolerance and virulence. In this study, we screened three isolates of Beauveria bassiana (Balsamo) Vuillemin and three of Cordyceps fumosorosea (Wize) (Hypocreales: Cordycipitaceae) for blastospore production and assessed desiccation tolerance by air drying. The virulence of these isolates were determined against Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) biotype B, Spodoptera frugiperda (J.E. Smith) and Chrysodeixis includens (Walker) (Lepidoptera: Noctuidae). The isolates ESALQ-1296 and ESALQ-3422 of C. fumosorosea and ESALQ-4958 of B. bassiana yielded blastospore concentrations above 1 × 10⁹ ml⁻¹, but only the two C. fumosorosea isolates retained viability rates above 75% after drying. Blastospores of both fungal species were more effective in killing the three insect species than aerial conidia. In summary, blastospores of C. fumosorosea ESALQ-1296 hold the best promise for broad-spectrum pest control in soybean.

中文翻译：

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球孢白僵菌和冬虫夏草对大豆害虫芽孢产生和毒力的比较分析。

孢子孢子是节肢动物害虫的酵母样感染细胞，可通过液体培养很快获得。但是，真菌分离物在生产，干燥耐性和毒力方面表现出惊人的变化。在这项研究中，我们筛选了三种球孢白僵菌（Balsver）Vuillemin和三株冬虫夏草（Wize）（Hypocreales：Cordycipitaceae）的芽孢孢子生产，并通过空气干燥评估了其耐干燥性。确定了这些分离株的毒力是针对烟粉虱（Bemisia tabaci（Gennadius）（半翅目：Aleyrodidae）生物型B，草地贪夜蛾（Spodoptera frugiperda）（JE Smith）和拟南芥属（Walker）（鳞翅目：夜蛾科）。的分离株ESALQ-1296和ESALQ-3422球孢白僵菌和球孢白僵菌的ESALQ-4958产生的芽孢孢子浓度高于1×10 ⁹  ml ^-1，但只有两个葡萄球菌的分离物在干燥后的存活率保持在75％以上。两种真菌物种的孢子孢子在杀灭这三种昆虫物种方面比气生分生孢子更有效。总之，C。fumosorosea ESALQ-1296的芽孢具有大豆广谱害虫防治的最佳前景。