N.S. Pasricha and S.K. Bansal. Potash Research Institute of India, Gurgaon, Haryana, India, 219 - C, Bhai Randhir Singh Nagar, Ludhiana, Block C, Ludhiana, India, Ludhiana, India
This paper highlights the results of several trials on crop production, done over a period of time across the country on the use of potassium in balanced fertilization. Even in soils, where available K levels were considered adequate a couple of decades ago, continuous and increased use of fertilizers other than K has quickly shifted their K status towards deficiency. Large area under cereal grains like wheat and rice makes the K nutrition of these crops important in the wake of increasing K deficiency with increased cropping intensity and larger harvests under high input conditions. Besides its role in improving the yield and quality of the crop, role of K in mitigating soil moisture stress can help improving crop performance in rain fed agriculture currently occupying more than 60% of the total cultivable area of the country. Development of plant resistance against pathogens and insect pest infestation through proper K fertilization of the crops, which has important environmental implications, is also highlighted in this paper. Amount of K fertilization has to be based on not only the K supplying power of the soil but also the level of crop harvests, level of use of other nutrients, type of crop produced and proportion of the crop removed in the harvest portion. Where vegetative portion is removed for fodder or fuel, the depletion of K is more rapid. Results suggest that for achievements in quality food production, use of potassium along with nitrogen and phosphorus fertilizers will require speedy implementation of policies that encourage farmers to use potash in balanced fertilization. Projected estimates suggest that proportion of K in fertilization has to be increased more than 5 fold if future need of quality food is to be met for increasing population in the country.