Plant genotype mediates cotton aphid (Aphis gossypii) response to plants colonized by the endophytic entomopathogen, Beauveria bassiana

Recent studies indicate that endophytic fungi, such as Beauveria bassiana, may play important roles in plant microbiome interactions with herbivorous insect pest species. Plant genotype may also influence microbiome interactions, and affect attractiveness of endophyte colonized plants to insect pests such as cotton aphids, Aphis gossypii. We conducted pairwise-choice host plant colonization assays with alate aphids using three cotton cultivars. A single alate was placed in a cage containing two seedlings with different genotypes, and the number of aphids on each plant was measured after seven days. The trials were conducted comparing responses to untreated seedlings, then repeated using B. bassiana treated seedlings. Aphid preference patterns for specific plant genotypes varied significantly in the presence versus absence of B. bassiana treatment.  Our results illustrate the importance of endophyte-host genotype interactions in mediating interactions with insects, and indicate that such effects should be considered in the use of fungal endophytes for pest management.