Foliar Bioinput Spraying Farmer Checklist for Successful Biological Crop Protection | Bacillus subtilis, Pseudomonas fluorescens, Beauveria bassiana, Metarhizium anisopliae, Lecanicillium lecanii and Bacillus thuringiensis

Foliar bioinput spraying is an important method of applying suitable microbial biopesticides, biofungicides and other biological crop-care products directly onto plant surfaces.

This application method may be used in vegetables, fruits, field crops, plantation crops, nurseries and protected cultivation systems when the selected product is suitable for the intended use.

Beneficial microorganisms such as Bacillus subtilis and Pseudomonas fluorescens may contribute to selected biological disease-management programs.

Beauveria bassiana, Metarhizium anisopliae and Lecanicillium species are entomopathogenic fungi used against certain susceptible insect pests.

Bacillus thuringiensis is a microbial insecticide used against specific insect larvae, depending on the bacterial subspecies, strain and formulation.

However, the performance of microbial foliar products depends on correct product selection, suitable spray preparation, microbial viability, target coverage and environmental conditions.

Farmers should remember that nutrient-related biofertilizers, microbial biofungicides and microbial biopesticides have different intended functions.

Following a practical checklist before, during and after spraying can help reduce avoidable application mistakes and support responsible biological crop protection.

Check the Target Pest, Microbial Product and Formulation

Before spraying, farmers should identify the crop, growth stage, target insect or disease and intended purpose of the treatment. Selected Bacillus subtilis and Pseudomonas fluorescens strains may be appropriate for certain biological disease-management applications, while Beauveria bassiana, Metarhizium anisopliae and Lecanicillium species are associated with management of susceptible insect pests; suitable Bacillus thuringiensis products target particular insect larvae. Farmers should verify the product's microbial strain, formulation, viable concentration, expiry date, storage instructions and authorized crop and target use. A product formulated for soil application should not automatically be used as a foliar spray without supporting instructions.

Check Spray Dosage, Water Quality and Mixing Procedure

Farmers should calculate the required product quantity using the recommended concentration and the spray volume needed for adequate crop coverage. For Bactostore powder products specifically recommending 5 grams per litre of water, the mixing quantities are 50 grams in 10 litres, 75 grams in 15 litres and 100 grams in 20 litres; other formulations must follow their own product-specific label rates. Clean water and a clean spray tank should be used, and wettable powder suspensions should be mixed thoroughly with suitable agitation during application. Water with unsuitable pH, excessive salinity, disinfectant residues or extreme temperatures may affect microbial viability, while incompatible chemical residues in the tank may reduce product performance.

Check Weather Conditions, Spray Equipment and Leaf Coverage

Before application, farmers should inspect the sprayer, nozzle condition, filter cleanliness, spray pressure and equipment calibration. Spraying should be planned according to the selected microorganism, target organism and prevailing weather conditions, avoiding strong winds, imminent rainfall and other conditions unsuitable for the product. Early morning or late afternoon may be appropriate for certain microbial formulations because intense sunlight and excessive heat can affect sensitive microorganisms, although product-specific guidance takes priority. Farmers should achieve uniform coverage of the intended plant surfaces, including leaf undersides when relevant, without excessive runoff, drift or unnecessary repeated spraying.

Check Chemical Compatibility, Crop Safety and Post-Spray Monitoring

Microbial foliar products should not automatically be mixed with fungicides, bactericides, insecticides, concentrated fertilizers, disinfectants or other biological products without verified compatibility information. Farmers should follow label instructions for tank mixing, application intervals, personal protective equipment, re-entry restrictions and any applicable harvest precautions. After spraying, the crop should be monitored for pest activity, fresh feeding damage, disease development, leaf condition and possible phytotoxicity. Repeat treatments should be based on product directions, pest or disease monitoring and the wider integrated crop-management program rather than an identical schedule for every microorganism.