Efficacy of the entomopathogenic fungus, Beauveria bassiana and Lecanicillium muscarium against two main pests, Bemisia tabaci (Genn.) and Tetranychus urticae (Koch), under geothermal greenhouses of Southern Tunisia

Abstract

Background The geothermal greenhouses in Southern Tunisia are an important axis of agricultural development. This sector faces many abiotic and biotic constraints that could threat its sustainability. Thus, the heated greenhouses encounter destructive pests such as the whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) and the two-spotted spider mite Tetranychus urticae (Koch) (Acari: Tetranychidae). Results This study aimed to assess the effect of the entomopathogenic fungi (EPF) Beauveria bassiana (strain ATCC and strain R444) and Lecanicillium muscarium strain Ve6 on simultaneous existence of T. urticae and B. tabaci in the host plants. The EPF had a significant effect on eggs and larvae of B. tabaci and on eggs and mobile forms of T. urticae in particular. The use of B. bassiana ATCC, B. bassiana R444 and L. muscarium strains Ve6 showed significant efficacies against B. tabaci larvae and eggs compared to untreated control. Indeed, the reduction percent of B. tabaci eggs varied between 42.65 and 58.52%. Thus, the efficacy against the number of B. tabaci larvae was in order to 65.04, 60.26 and 55.52% of B. bassiana strain ATCC, B. bassiana strain R444 and L. muscarium strain Ve6, respectively. In addition, these EPF were very effective on T. urticae eggs with a percentage reduction greater than 92.86%, whereas the percentage reduction in the T. urticae mobile forms varied between 95.11 and 98.52%. Conclusions Use of EPF will be an imperative to develop directed interventions at the integrated management of these two pests in protected and geothermal crops.

Evaluation of Biopesticides for Management of Bemisia tabaci Middle East-Asia Minor 1 (Hemiptera: Aleyrodidae) in Florida

“…The most notable reduction occurred when BG was combined with SX (sample 2) in both trials, with nymph counts being reduced by 41.2% during the spring and by 73.5% during the fall. This aligns with a previous report that B. bassiana treatments significantly impacted B. tabaci populations, reducing egg numbers by up to 65% and nymph numbers by up to 58% compared to untreated plants [ 45 ]. In our study, we used the highest concentrations of these materials according to each product label.…”

“…Biochemical insecticides, such as insecticidal soaps and mineral oils, have shown potential in managing B. tabaci populations by mechanisms of action that likely do not select for resistance, including suffocation and anti-feedant properties [ 37 , 38 , 39 , 40 , 41 , 42 ]. Similarly, microbial insecticides containing Beauveria bassiana (Balsamo) Vuillemin (Hypocreales: Cordycipitaceae) and Cordyceps javanica (Kobayasi & Shimizu) (Hypocreales: Cordycipitaceae) as active ingredients have demonstrated efficacy against B. tabaci through the pathogenic activity of the fungi [ 41 , 43 , 44 , 45 ]. Despite the potential benefits of biopesticides, their performance can be variable and influenced by environmental conditions such as UV light, as well as application methods [ 43 , 46 , 47 , 48 ].…”

Soil and Sediments in Natural Underground Ecosystems as a Source of Culturable Micromycetes: A Case Study of the Brestovská Cave (Western Tatras, Slovakia)

“…Although it has been found previously in Slovakian caves, there are no reports on its occurrence in other regions of the world [14,92]. L. muscarium presence in the caves may be supported by its psychrotolerance, with the ability of some strains isolated from Antarctica to propagate even at 0 • C. Facilitation of the development in harsh conditions may be also due to the activity of lytic enzymes, degrading various substrates like chitin [93].…”

Evaluation of Biopesticides for Management of Bemisia tabaci MEAM1 (Hemiptera: Aleyrodidae) in Florida

“…Biochemical insecticides such as insecticidal soaps and mineral oils have shown potential in managing B. tabaci populations by mechanisms of action that likely do not select for resistance, including suffocation and anti-feedant properties [37][38][39][40][41][42]. Similarly, microbial insecticides containing Beauveria bassiana and Cordyceps javanica as active ingredients have demonstrated efficacy against B. tabaci through the pathogenic activity of the fungi [41,[43][44][45]. Despite the potential benefits of biopesticides, their performance can be variable and influenced by environmental conditions, UV light, and application methods [43,[46][47][48].…”