The Investigation of Effect of Bacteria in Biological Control of Red Spider Mite (Tetranychus spp.) and Plant Yield Parameter in Cotton (Gossypium hirsutum L.)

The purpose of this study was to assess the usability of two bacterial

strains, namely Bacillus subtilis PA1 and Paenibacillus azotofixans PA2, for the

biological control of red spider species, and their effects on plant quality and yield

in cotton under field conditions. The experiments were conducted at three different

locations with multiple replications. As a control, a commercial preparation

containing Lambda-Cyhalothrin as the active ingredient was used. The obtained

results from the study revealed that the application of the bioagent formulation led

to a significant decrease in the density of Tetranychus spp. at different biological

stages, ranging from 59.22% to 61.07%, when compared to the control group.

Additionally, several important plant growth parameters showed remarkable

improvements. The number of fruit branches increased by 130.20%, plant crown

diameter by 88.16%, plant height by 40.15%, the number of flowers by 21.25%, the

number of wood branches by 18.13%, the average number of cocoons by 126.53%,

and cocoon weights by 54.65% significantly across all three trial parcels. The

successful implementation of the bacterial application for pest control had a positive

impact on cotton yield. Bulk cotton yield increased by 80.03%, and fiber yield

increased by 82.17%. Consequently, the bacterial formulation containing these two

bacteria demonstrated its potential as a biopesticide in cotton cultivation, effectively

controlling pests while also playing a crucial role in enhancing productivity. Overall,

the study suggests that using the bioagent formulation consisting of Bacillus subtilis

PA1 and Paenibacillus azotofixans PA2 could be an effective and environmentally

friendly approach for pest control in cotton farming, leading to increased

productivity.