Insecticidal Potential of Eco-friendly Mycoinsecticides for the management of fall armyworm (Spodoptera frugiperda) under in vitro condition

Fazlullah, Shahid Hussain, Muzammil Farooq, Muhammad Naeem Aslam and Naeem Zada

Abstract: The invasive polyphagous pest Fall armyworm (FAW) Spodoptera frugiperda, (Lepidoptera: Noctuidae) is a migratory pest of maize crops in Asia and other countries including Pakistan. It is mostly fed on leaves at the larval stage this pest can be controlled by various types of pesticides globally but now resistance has come in pest against insecticides. So, we can also control this pest by other control strategies including physical, biological, and mechanical Eco-friendly Mycoinsecticides fungus Beauveria bassiana, Trichoderma, and Metarhizium anisopliae instead of chemical control method. By this, we can save our ecosystem and nature from the hazardous effects of chemicals. According to in vitro bioassay of entomopathogenic fungi like Beauveria bassiana Trichoderma and Metarhizium anisopliae under control conditions Metarhizium anisopliae was found very effective on fall armyworm 1st 2nd 3rd and 4th instar larvae and mortality percent was recorded 85.5% on 1st 2nd and 3rd instar larvae at 40ppm dose while minimum mortality was recorded 18.6% on 10ppm dose of Trichoderma during bioassay under control condition. During the second instar larvae of bioassay entomopathogenic fungi, Metarhizium anisopliae was recorded as very effective and showed mortality of FAW up to 83.3% at a dose of 40ppm after exposure of three days at 25℃ approximately. While minimum mortality of FAW was recorded at 10 ppm after exposure for three days. In 2nd instar larvae, exposer Metarhizium anisopliae was found to have entomopathogenic potentials and Couse highest mortality of FAW the minimum mortality was recorded at 48% on 10ppm dose exposure of M. anisopliae after three days at 25℃ and approximately 53% humidity. The studies show that the entomopathogenic potentials of fungi decrease with increasing larval instars. On 3rd and 4th instar larvae only M. anisopliae was recorded as effective and mitigated the larvae population 78.5% at 40 ppm and 55.8% mortality was observed on 4th instar larvae after exposure of three days among all Metarhizium anisopliae was found potential insecticidal properties as compare to Beauveria bassiana and Trichoderma. This comparative study shows that M. anisopliae was found highest insecticidal properties as compared to Beauveria bassiana and Trichoderma. So, M. anisopliae was found broad spectrum insecticidal potentials on FAW multiple larval stages under control conditions. Among all only Metarhizium anisopliae was found with exophytic sporulation characters and dynamic insecticidal potentials while Beauveria bassiana and Trichoderma were recorded as endo sporulation characters.

Keywords: Insecticidal potential, Mycoinsecticides, endosporulation, FAW, Exophytic sporulation

Date published: 2023-02-24