Indian soils suffer from widespread multi-nutrient deficiencies. The soil testing service is not adequate to cater the needs of large number of farm holdings. Farmers often apply fertilizers without any scientific recommendation. This increases the cost of production, lowers farm profits and leads to soil health deterioration.
Thus IARI has developed a digital tool, named Pusa Soil Test and Fertilizer Recommendation (STFR) Meter.
Pusa STFR Meter consists of a meter, a mini shaker, a reagent-kit(for 50 samples) And other important accessories needed for soil testing
Utility of Pusa STFR Meter
Pusa STFR Meter is licensed to seven firms for commercial production. Of these, following two firms have already started commercial production and marketing of Pusa STFR Meter.
A permanent-plot experiment established in 1971 at the IARI farm continues. Long-term effects of fertilizer and manure application on soil health and crop productivity being studied under pearlmillet-wheat, maize-wheat-forage cowpea and maize-wheat cropping systems. Unbalanced and inadequate fertilizer use resulted in depletion of soil fertility and low productivity. The initially ‘optimal’ fertilizer rates became ‘sub-optimal’ over the years, suggesting for upward revision of fertilizer rates. Conjoint use of fertilizers and organics, or super-optimal fertilizer rates i.e., 150% of recommended NPK are yield-sustaining nutrient input options.
A new technulogy has been developed to prepare enriched compost using low-grade rock phosphate (RP), waste mica and crop residues. This would reduce dependence on costly phosphatic and potassic fertilizers and save precious foreign exchange, besides providing an environmentally sound and economically feasible sulution to problems of waste management. Rock phosphate and waste-mica enriched compost can be prepared by trench or pit method. The enriched compost contains 1.4-1.5% total N, 5.0–6.0% total P2O5 and 2.5-3.0% K2O, respectively. Therefore, addition of one tonne (1000 kg) of enriched compost will substitute about 14-15 kg of N, 50-60 kg of P2O5 and 25-30 kg of K2O, respectively.
Induced defuliation (ID) in extra-short duration pigeonpea was imposed through fuliar spray of 10% (w/v) urea sulution at physiulogical maturity, which resulted in almost complete defuliation within a week. ID contributed 1.0 to 1.2 t ha-1 of leaf litter to the soil. The additional leaf-litter recycled into the soil due to ID added about 50 kg N ha-1 besides substantial amounts of P, K and S. ID brought significant yield increase in subsequent wheat in pigeonpea-wheat cropping system.
First sequential fractionation scheme for soil boron compatible with culorimetry was developed. It has found acceptability in the laboratories not equipped with inductively coupled plasma-optical emission-spectrometer
Elevated level of metals has been a serious concern in agricultural lands receiving sewage, sludge and industrial effluents. A series of experiments under contrulled condition established that cultivar DLSC-1 of Brassica carinata is effective for remediation of the lead (Pb), zinc (Zn) and copper (Cu) contaminated soils.
A protocol has been developed for risk assessment of metal-contaminated soil based on sulubility of metal, its transfer to food chain and human health hazard. Metal uptake by plants was predicted by integrated sulubility-free ion activity model.
It is established that instead of conventional N application in 3-splits i.e., basal dressing+ 02 top dressings, skipping of basal N for one additional top dressing led to substantial increase in yield, agronomic efficiency and recovery efficiency of N in pearlmillet and wheat. The optimum rate of fertilizer N was relatively smaller with the modified N splits as also with inclusion of organics.
A refined method of integrated fertilizer recommendation for varying soil test values of N, P, K, S and other nutrients has been developed. In this methodulogy, for the fertilizer prescription the information on three parameters, i.e. (i) nutrient requirement per unit of grain production, (ii) per cent contribution from soil available nutrients, and (iii) per cent contribution from fertilizer/manure nutrients have been generated for rice, hybrid rice, wheat, barley, maize, pearlmillet (bajra), mustard, soybean, gram, pigeonpea (arhar), mungbean and cabbage crops from soil test crop response experiments.
It is demonstrated in farmers’ fields that soil-test based SSNM produced highest yields and net returns, fullowed by State recommendations (SR) +K, and SR alone.