Vol. 11, Issue 1, Part C (2024)

Author(s): Jenifer Jincy T, Biji CP and A Vijaya Chithra

Abstract: Food production and disease control are two critical challenges that humanity faces in the 21^st century. There is an urgent need for eco-friendly control tools for fighting mosquito vectors and agricultural pests. The current study aimed to isolate the fungal strain Humicola fuscoatra from the leaves of Adhatoda vasica and extract their secondary metabolites using ethyl acetate. The effectiveness of the crude extract against the dengue vector Aedes aegypti and the cabbage pest Plutella xylostella was then evaluated. The molecular identification of isolated H. fuscoatra was accomplished through PCR amplification using a universal primer (ITS-1 and ITS-2). The ethyl acetate extracts of the fungus H. fuscoatra exhibited higher toxicity against both insects. The LC50 values of ethyl acetate extracts of the fungus H. fuscoatra ranged between 132.712 and 450.163 ppm for 1st instar larvae and pupae of Ae. aegypti, as well as 287.071 and 656.694 ppm for 1st instar larvae and pupae of P. xylostella. The ethyl acetate extracts of the fungus H. fuscoatra significantly reduced the longevity and fecundity of Ae. aegypti and P. xylostella adults. GC-MS analysis indicated the presence of some identified compounds as insecticides in ethyl acetate extracts of fungi such as: Hexadecanoic acid (15.07%), octadecadienoic acid (13.74%), Hexadecanoic acid, methyl ester (12.89%), Hexadecan (6.43%), Octadecan (8.33%) and Phenol, 2,4-bis (1,1-dimethylethyl (2.23%). This study provides valuable insights into the ethyl acetate extracts of the fungus H. fuscoatra from plants and their potential in fighting arthropods of medical and agricultural significance. The findings suggest that the tested products could be potentially useful for the development of economically viable pest control approaches.

DOI: 10.22271/23487941.2024.v11.i1c.759