The aim of the present study was to evaluate the artificial establishment of Beauveria bassiana and Metarhizium anisopliae as endophytes in maize plants, and its effect in controlling the fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) larvae. The commercial strains B. bassiana Bb-18 and M. anisopliae Ma-30 were concentrated at 1 × 108 conidia ml−1, and the soil drench method was used to establish them as endophytes in maize plant parts. The biological control assays were conducted under laboratory conditions on second and fourth larval instars of S. frugiperda. B. bassiana colonized roots, stems, and leaves of maize tissues. However, a high occurrence of B. bassiana was obtained in roots than leaves and stems with 25, 10, and 5 isolations, respectively, whereas M. anisopliae was only acquired on roots. Both entomopathogenic fungi caused (100%) mortality on the second instar larvae. In addition, B. bassiana and M. anisopliae killed (87 and 75%) of the fourth larval instars, respectively. The fungus M. anisopliae caused the highest sporulation rates during the study. These results suggest that the entomopathogenic fungi might contribute to a sustainable S. frugiperda management in maize production in Cuba.

中文翻译：

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玉米白僵菌和拟南芥的内生建植及其对节食夜蛾幼虫的影响（鳞翅目：夜蛾科）

本研究的目的是评估作为植物内生菌的球孢白僵菌和拟南芥的人工建立，以及其在控制秋季夜蛾夜蛾夜蛾幼虫（鳞翅目：夜蛾科）幼虫中的作用。将商品菌株B. bassiana Bb-18和M. anisopliae Ma-30浓缩至1×108分生孢子ml-1，并采用土壤浸湿法将其建立为玉米植物内生菌。在实验室条件下对弗氏链球菌第二和第四龄​​幼虫进行生物学对照测定。B. bassiana定居在玉米组织的根，茎和叶上。然而，与叶和茎相比，分别在根，叶和茎上分别获得25、10和5个分离株的球孢杆菌发生率很高，而无芒分枝杆菌仅在根上获得。两种昆虫病原真菌均导致第二龄幼虫死亡（100％）。此外，球孢杆菌和无芒分枝杆菌分别杀死了第四只幼虫（87％和75％）。在研究过程中，真菌M. anisopliae引起了最高的孢子形成率。这些结果表明昆虫病原真菌可能有助于古巴玉米生产中可持续的S. frugiperda管理。