Foliar Bioinput Spraying Step-by-Step Application Guide for Farmers | Bacillus subtilis, Pseudomonas fluorescens, Trichoderma, Beauveria bassiana, Metarhizium anisopliae and Verticillium lecanii

Foliar bioinput spraying is an agricultural application method in which suitable microbial products are sprayed onto plant leaves, stems and other above-ground crop surfaces.

This method is commonly used for biological pest management, selected foliar disease-management programs and certain plant-growth-promoting applications.

Beneficial microorganisms such as Bacillus subtilis, Pseudomonas fluorescens, Beauveria bassiana, Metarhizium anisopliae and Lecanicillium species may be considered for foliar applications when the product formulation and registered or permitted use support the intended treatment.

Trichoderma species are primarily associated with soil and root-zone applications, although certain strains and formulations have also been investigated for foliar use.

Farmers should understand that biofertilizers and microbial biopesticides have different intended functions. Microorganisms used for nutrient-related processes are not automatically suitable for controlling insects or foliar diseases.

Successful foliar spraying requires appropriate microbial selection, correct dilution, suitable water quality, uniform spray coverage and favorable environmental conditions.

Selecting Suitable Microbial Bioinputs for Foliar Application

Farmers should first identify the crop, growth stage, target pest or disease and intended purpose of the microbial application. Selected strains of Bacillus subtilis and Pseudomonas fluorescens may be used in appropriate biological foliar disease-management programs, while Beauveria bassiana, Metarhizium anisopliae and Lecanicillium species are entomopathogenic fungi used against certain susceptible insect pests. The suitability of each microorganism depends on its strain, formulation, target organism, application instructions and applicable regulatory authorization. Farmers should verify the product label, microbial concentration, expiry date and recommended application method before preparing a spray solution.

Preparing the Microbial Spray Solution and Correct Dilution

A clean spray tank should be filled partially with suitable water before adding the measured quantity of the selected microbial product according to its label instructions. For Bactostore powder products specifically recommending 5 grams per litre of water for foliar spraying, the corresponding mixing quantities are 50 grams in 10 litres, 75 grams in 15 litres and 100 grams in 20 litres of water; this concentration must not be applied universally to products with different label rates. The suspension should be mixed thoroughly and maintained uniformly during spraying, particularly when using wettable powders or formulations containing insoluble carrier particles. Farmers should avoid preparing excessive quantities of spray suspension and should use the mixture within the period recommended for the product.

Applying the Spray with Proper Coverage and Equipment

Before spraying, farmers should inspect the sprayer, nozzle, filters, pressure settings and tank cleanliness to ensure proper operation. The spray should be directed toward the plant surfaces and pest locations identified in the product instructions, including the undersides of leaves when relevant to the target organism. Suitable nozzle selection, spray pressure and walking speed help achieve consistent coverage while minimizing unnecessary runoff and drift. Farmers should avoid spraying during strong winds, imminent rainfall or unsuitable temperatures and should follow the product label for personal protection, re-entry intervals and any other safety precautions.

Checking Spray Timing, Compatibility and Crop Response

Microbial sprays should be applied under environmental conditions appropriate for the selected microorganism, because temperature, sunlight, humidity and rainfall may influence survival and biological activity. Farmers should not automatically mix microbial products with fungicides, bactericides, disinfectants, concentrated fertilizers or other pesticides without verified compatibility information. After spraying, farmers should monitor pest activity, new crop damage, leaf condition and any signs of phytotoxicity, while maintaining an integrated crop-management program. Repeat applications, where necessary, should follow product-specific directions and observed field conditions rather than a fixed schedule applied to every crop or microorganism.