Beauveria bassiana, an entomopathogenic fungus, can exist asymptomatically as an endophyte in many plants. This study aimed to determine the efficiency of B. bassiana colonization of tomato plants using different inoculation methods, and how colonization of the host plant affects the key pest of tomato, the whitefly Bemisia tabaci. To confirm fungal colonization efficiency, nested PCR technique was used to detect B. bassiana sequences in Solanum lycopersicum. Distribution of the fungus within the plant parts was determined by selective medium. Tomato growth parameters were determined with plants that had been inoculated using direct spraying or irrigation of the rhizosphere. B. tabaci performance assays were carried out in a cage, and preference to treatments was determined using Y-tube olfactometer studies. Results show that B. bassiana can effectively colonize tomato, with colonization rate using leaf spraying reaching 100% within 14 days. Fungal presence was not uniformly distributed among plant parts, but was biased towards the inoculation sites. For inoculation, conidial suspension sprayed at 1 × 108 conidia/ml resulted in the highest number of isolated colonies in leaf tissue, 8.5 ± 2.02 colonies per 2 g of fresh tissue (F4,19 = 2.779, P = 0.045), and reached the lowest with root treatment. Although only small differences were observed among the growth indicators, leaf spray inoculation resulted in a significant positive influence on plant growth (PC1 55.7% contributions scores = 2.645) in further Principal component analysis. As for the feeding selectivity, B. tabaci preferred uninoculated plants. In Y-tube olfactometer assay, 80.5% of adults selected uninoculated plants. These findings add to the understanding of the interactions between B. bassiana and plants and indicate the potential of expanding the use of entomopathogenic fungi for crop protection.
A new pseudoscorpion, Lagynochthonius bailongtanensis sp. nov., is described and illustrated from specimens collected in a cave in Luoping County, Yunnan Province, China. This species is notable in being strongly troglomorphic. A new identification key is provided to all known Chinese representatives of the genus Lagynochthonius.
1 April 2014 in Experimental and Applied Acarology
A new pseudoscorpion species, Bisetocreagris xiaoensis Li & Liu, sp. n., is described and illustrated from specimens collected in caves in Yanjin County, Yunnan Province, China. An identification key is provided to all known cavedwelling representatives of the genus Bisetocreagris in the world.
30 August 2023 in Journal of Agricultural and Food Chemistry
Beauveria bassiana acts as an endophytic fungus that controls herbivorous pests by stimulating plant defenses and inducing systemic resistance. Through multiomics analysis, 325 differential metabolites and 1739 differential expressed genes were observed in tomatoes treated with B. bassiana by root irrigation; meanwhile, 152 differential metabolites and 1002 differential genes were observed in tomatoes treated by local leaf spraying. Among the upregulated metabolites were α-solanine, 5-O-caffeoylshikimic acid, clerodendrin A, and peucedanin, which demonstrated anti-insect activity. These differential metabolites were primarily associated with alkaloid biosynthesis, flavonoid biosynthesis, and tryptophan metabolism pathways. Furthermore, the gene silencing of UDP-glucose:sterol glucosyltransferase, a gene involved in α-solanine synthesis, indicated that B. bassiana could inhibit the reproduction of whiteflies by regulating α-solanine. This study highlighted the ability of B. bassiana to modulate plant secondary metabolites and emphasized the significance of understanding and harnessing multitrophic interactions of endophytic B. bassiana for sustainable agriculture.