Entomopathogenic Action of Wild Fungal Strains against Stored Product Beetle Pests

Abstract

There is ample evidence that entomopathogenic fungi can be used as alternative biological control agents for the management of insect pests in storage facilities. As the market demands more environmentally friendly methods and chemical insecticides become increasingly obsolete, more studies are being conducted to evaluate new strains of entomopathogenic fungi for their efficacy in storage facilities. In this context, we tested ten species of fungi isolated from soil, belonging to the genera Cladosporium, Condenascus, Lecanicillium, and Penicillium, for their long-term effects on economically important beetle species. Whole wheat was directly sprayed with a conidial suspension of 108 spores/Ml of each of the tested fungi and then adults of Sitophilus granarius, S. oryzae, S. zeamais, Rhyzopertha dominica, and Trogoderma granarium were placed on the sprayed medium to study the mortality effects. Significantly higher mortality than the control was observed in all treatments. The lowest LT50 (9.164 days) was observed in T. granarium infected with Penicillium goetzii. The isolate with the strongest results was L. dimorphum, which recorded remarkably low LT50 values in S. oryzae (~11 days), R. dominica (~12 days), T. granarium (~10 days), and S. granarius (~13 days). However, for S. zeamais, it was more than 16 days. Our results confirm the existing literature on the efficacy of EPF on storage beetles, suggest the possible virulence of wild untested strains, and also highlight the importance of EPF specificity.

Pathogenicity of the Steinernema feltiae TUR-S3 (Rhabditida: Steinernematidae) Isolate on Oryzaephilus surinamensis (Coleoptera: Silvanidae) and Tribolium confusum (Coleoptera: Tenebrionidae)

“…Various factors in post-harvest storage can lead to a loss in product quality (Galstyan et al, 2019;Olorunfemi and Kayode, 2021), with storage pests being a major contributing factor to yield loss. Therefore, controlling storage pests holds significance for food supply (Hassan et al, 2023;Mantzoukas et al, 2023).…”

First Record of Flavocillium subprimulinum (Cordycipitaceae, Hypocreales) in Mexico: Morphological and Molecular Characterisation, Nematocidal Activity of Its Liquid Culture Filtrates against Haemonchus contortus and Protease Activity

“…One of the most widely studied fungal genera belonging to this class is Lecanicillium. Species classified into this genus are potential biocontrol agents with important lethal activity against aphids, scales, whiteflies, thrips, mealy bugs, nematodes, and other insect pests [9][10][11]. Lecanicillium subprimulinum was reported by Huang et al as a novel species from Baoshan, Yunnan, China [12].…”

Susceptibility of Rhyzopertha dominica (Coleoptera: Bostrichidae) and Sitophilus oryzae (Coleoptera: Curculionidae) to the fungal entomopathogen Beauveria bassiana (Balsamo-Crivelli) Vuillemin s.l. (Hypocreales: Clavicipitaceae)

“…Current trends in integrated pest management are oriented towards preserving the environment together with the use of natural biopesticides with less toxicity. Among these products are the entomopathogenic fungi (14,20).…”

“…The species within the genera Beauveria and Metarhizium are widely used due to their specificity and effectiveness as biological insecticides (11,22,26,27). Several studies have demonstrated the capacity of entomopathogenic fungi to protect stored seeds and have demonstrated their insecticidal capacity to control different beetles (3,9,10,13,14) highlighting the importance of conducting bioassays for the selection of highly virulent isolates given the high genetic variability presented by these microorganisms.…”