Beauveria bassianana a fungus that causes white muscardine disease in the arthropods is an entomo-pathogenic fungus. It is recently being used as a biological insecticide for controlling the infestation of pests on crops, also it is being used for bedbugs and malarial mosquito control. These endophytic fungi are spread vastly across the soil and don’t seem to harm the plants (hosts), as they are in mutualistic relationships. With the added benefit of protection for the host plant from different pests, this funguscan produce compounds that are toxic for the insect pests, they are also believed to cause pathogenic resistance in the plants against the invaders. Endophytic entomopathogenic fungi (EEPF) can be either sprayed or inoculated on the plants. Since there is an elevated interest in the use of EEPF for pest and disease control in plants, a team of researchers from Taif Governorate in KSA conducted a study to evaluate the fungus (Beauveria bassianana) against piercing-sucking pests on grapevine by spraying.
Grapevine is an important economical fruit for the Taif region in KSA and is consumed in the form of juice and raisins. The famous aphid pests infesting grapevines are Shimer, also known as, Aphis illinoisensis, Glover, or Aphis gossypii. The Gennadius, sweet potato whitefly is also considered pests for the grapevines.These pests can infest the trees, young terminal shoots, stems, young leaves, and fruit clusters, which causes the early fall of the grape berries. These infestations also harm the quality of grapes. The Gennadius is known for damaging the production of honeydew. Another enemy for the grapes is thrip, like Pergande, Uzeli, and Lindeman, as they feed on the young leaves and damage them, at the same time they damage the flowers by affecting blooming.
Biocontrol agents have the potential benefit of adapting to climate conditions, being more targeted, environmentally friendly, and economic. One such agent is B. bassiana against pests; A. illinoisensis, B. tabaci, and F. occidentalis on the grape plants.
The fungus was isolated, propagated, and prepared in suspensions kept at 4°C. The plants were treated in a Randomized Complete Block Design (RCBD) with 3 treatments that are; 5-day, 10 day and 15-day intervals in the early morning. Aphids, whiteflies, and thrips were counted from the leaves before and after an experiment for infestation analysis.
The study suggested a reduction in the infestation of aphids at all the 3 intervals. Whereas, the white fly control was also evident from the experiment. White fly control was less comparing to aphid control, which could be due to the pathogenicity of the fungi isolates or because the nymphal in stars remained immobile and flattened on the leave and not got exposed to the conidia. The thrips control was also evident after spraying them with B. bassiana but it was not much significant in the first spray.
The results indicated the EEPF were effective in controlling piercing-sucking insect pests like aphids, whitefly, and thrips. Which could be great facilitation in organic grapevine production. It has the potential to replace chemical treatment, helping the environment and benefiting consumer health. Further studies should explore the efficacy of the isolates of fungi on other crops for added economic benefits.
Aphids, whitefly, thrips, Beauveria bassianana, white muscardine disease, organic farming, organic pesticide, Grapevine, A. illinoisensis, B. tabaci, and F. occidentalis.