Mineral nutrition and fertilizer response of grain sorghum in India - A review over the last 25 years

Researches on the mineral nutrition and fertilizer response of grain sorghum (Sorghum bicolor (L) Moench) carried out during the last 25 years in India are reviewed here. In general, N,P,K, Fe and Mn concentrations in vegetative plant parts decreased with crop age, while the concentrations of Ca, Mg and Cu increased. The concentration of N and P increased in panicle or grains of sorghum with advance in crop age. The seasonal change for other nutrients has not, however, been studied. Accumulation and uptake of N,P, and K by grain sorghum were characterized. Usually N and P accumulated slowly compared with the rapid accumulation of K in early crop growth stage and vice-versa in later stages of growth. As against the sizable mass of N and P into panicle, K was partitioned into stalk. Fertilizer responses to N and P were observed throughout India. Improved varieties and hybrids of sorghum responded to N rates ranging from 60 to 150 kg N ha-1, whereas a response to P application was observed up to 40 kg P ha-1. Although responses to K application had been inconsistent, an increase in grain yield of sorghum was observed due to 33 kg K ha-1. A balanced fertilizer schedule consisting of 120 kg N ha-1, 26 kg P ha-1, 33 kg K ha-1 and 15-25 kg Zn504 ha-1 is recommended for improved productivity of grain sorghum. It is concluded that systematic research efforts should be directed so as to identify problem soils showing deficiencies and toxicities of different nutrients. Characterization of the seasonal changes in the concentration and uptake of different nutrients and determination of critical concentration and hidden hunger of different nutrients in plant tissues would lead to the recommendation of balanced fertilization for different sorghum-growing regions in India. © 1982 Martinus Nijhoff/Dr W. Junk Publishers.