Vesicular Arbuscular Mycorrhizae (VAM)
Mycorrhizae increases availability of major nutrients like, nitrogen, phosphorus and potassium and also certain micronutrients like zinc, calcium, iron, magnesium and manganese.
Mycorrhizal inoculation enhances absorption of water and moisture, and also enhances tolerance to drought. It produces specific antibiotics, which immobilize and kill soil borne pathogens. It also reduces requirement of chemical fertilizers upto 40% of recommended dose.
Vesicular arbuscular mycorrhiza is mostly recommended for upland crops especially for potted plants and tissue culture plantlets.
Commercially it is available as carrier based inoculum.The recommended method of application includes seed treatment, seedling dip and direct soil application along with organic manure.
Take 500gram culture in a plastic tray/basin. Moisten the seeds by sprinkling water or rice-gruel water (500 ml). Add moistened seeds, mix well and dry in shade for 30 minutes. The treated seed should be sown immediately.
For seedling dip the slurry of the culture is prepared by mixing 500g culture with 2.5 litre of water. The roots of the seedlings are dipped in the slurry for 15-20 minutes before transplanting.
For soil application one kilogram of the culture is mixed with 25 kilogram of FYM or compost and applied directly in the soil.For crop of six-month duration, the recommended dose is 1-2 kg/ha. This can be increased to 2-4 kg/ha for crops more than six months duration.
For perennial crops, 10 to 25 gram of the bio fertilizer is to be applied in the root zone during the first year and 25 to 50 gram during subsequent years. This can be done at the time of sowing, transplanting or during intercultivation.