Effect of Added Phosphate and Zinc on Their Availability, Uptake and Yield of Pearl Millet in Presence of Calcium Carbonate and Farmyard Manure

The effect of P and Zn, in absence and presence of CaCO₃ and FYM, on their availability, uptake and dry matter yield of bajra (pearl millet) was studied in a greenhouse experiment. Application of P increased the yield, while Zn failed to do so, but the combined addition of P and Zn further enhanced the yield. Increasing levels of P and Zn raised their concentrations and uptake in plants but more than 50 ppm P showed antagonistic effect on Zn nutrition. Both P and Zn increased their availability in soil but that of the latter was depressed by the former.

Calcium carbonate decreased the available P and Zn in soil, plant P concentration, uptake and yield but concentration and uptake of Zn were more. FYM helped in maintaining higher levels of available P and Zn irrespective of the presence of CaCO₃, and in increasing the yield, concentration and uptake of the two nutrients. In absence of CaCO response to P was more pronounced than of Zn while in its presence the trend was reversed.