Efficacy of Three Entomopathogenic Fungi Alone or in Combination With Diatomaceous Earth Modifications for the Control of Three Pyralid Moths in Stored Grains

Abstract

The efficacy of Natural diatomaceous (DE) alone and combined with three fungal pathogens: Beauveria bassiana, Metarhizium anisopliae and Isaria fumosorosea against three moth species, Plodia interpunctella, Ephestia cautella and E. kuehniella was evaluated. Modified diatoms with Calcium hydroxide (Ca-DE) and modified diatoms with Sodium hydroxide (Na-DE) were the highlight treatments against tested insects and achieved the highest mortality percentages. E. kuehniella achieved the highest tolerant to tested DEs. B. bassiana was the most effective fungus alone against the three tested insects. Ca-DE and Na-DE treatments strongly enhanced the potency of the tested fungi. E. kuehniella was more susceptible to M. anisopliae and B. bassiana. Larvae of P. interpunctella and E. cautella were more tolerant to I. fumosorosea alone than E. kuehniella. In most cases, DE combinations with tested fungi had synergistic effects, while in E. cautella, modified diatoms with Aluminium hydroxide (Al-DE) decreased the efficacy of M. anisopliae and I. fumosorosea. Also, Al-DE and DE impaired the efficacy of I. fumosorosea against E. kuehniella. The egg production was highly suppressed by combination of Ca-DE followed by Na-DE with tested fungi in comparison to untreated control. The combination of Ca-DE/Beauveria bassiana strongly suppressed the number of deposited eggs of P. interpunctella (54.6±5.8 eggs/female), in comparison to untreated control (288.3±3.4 eggs/female).The most effective DEs modification were Ca-DE and Na-DE had insecticidal, repellent and ovicidal effects against tested insects and they had synergistic effects on the potency of tested fungi.

Simultaneous Use of Entomopathogenic Fungus <i>Beauveria bassiana</i> and Diatomaceous Earth against the Larvae of Indian Meal Moth, <i>Plodia interpunctella</i>

“…This result approved the finding of Sabbour et al [13], however, the LC 50 of fungus in their study was 1.29 × 10 9 con. mg −1 which was much greater than that of our finding, 1 × 10 5 con.…”

“…Some reports have pointed out to the promising control effects of B. bassiana on Indian meal moth [12] [13]. However the fungi encountered some limiting factors to show adequate level of pest control.…”

The Time–Concentration–Mortality Responses of Western Flower Thrips, Frankliniella occidentalis, to the Synergistic Interaction of Entomopathogenic Fungus Metarhizium flavoviride, Insecticides, and Diatomaceous Earth

“…Likewise, Wakil et al found that B. bassiana combined with DE or the neonicotinoid insecticide thiamethoxam increased the mortality of R. dominica adults, compared with individual treatments, and a significant additive effect was observed [32]. Similar synergistic interactions were observed when the tested fungi B. bassiana, M. anisopliae, and I. fumosorosea were combined with DE against Plodia interpunctella, Ephestia cautella, and Ephestia kuehniella [51]. Therefore, it is important to understand how a pathogen interacts with other insecticides and adjuvants.…”

“…Therefore, combining fungal biocontrol agents with adjuvants and Insects 2020, 11,93 3 of 20 other insecticides with good compatibility is an effective and reliable solution to improve the pest control effect [15,18,32,39,48]. Numerous studies have reported that the combination of EPF with insecticides [44,[48][49][50], DE [34,39,51,52], and with insecticides and DE have significantly improved their pest control efficacies [15,32,33,35]. For example, Nian et al [49] demonstrated that combining I. fumosorosea with sub-lethal doses of the insecticides beta-cypermethrin and bacillus thuringiensis caused synergistic effects against Plutella xylostella larvae under laboratory conditions.…”

Relative Susceptibility of Four Coleopteran Stored-product Insects to Diatomaceous Earth SilicoSec®

“…Diatomaceous earths are naturally occurring siliceous sedimentary mineral compound formed from the fossils of tiny phytoplanktons (diatoms) which absorb the epicuticular lipids of the insect cuticle, causing death Corresponding author: Baba Gana Jugudum Kabir, Dr., Ph.D., research field: stored products entomology. through desiccation [9]. They are known to protect commodities against stored-product pests in two ways.…”