Nutrient uptake and content in sorghum cultivars (Sorghum bicolor L) under summer environment

Abstract

Performance of 10 sorghum cultivars (CSH13, CSH14, CSH16, CSH25, CSH30, CSV15, CSV20, CSV23, CSV27 and SPV462) for nutrient composition and nutrient uptake was determined under two dates of sowing (16 February and 3 March) at ICAR Research Complex for Eastern Region Patna, during summer season of 2015 and 2016. Study revealed that difference in sowing dates did not influence the nutrient contents (N, P, K, S, Zn, Fe and Cu) of grain of sorghum. But in case of stover, K, Zn and Cu content did change in two dates of sowing, while the content of other nutrients does not change in stover also. The 16th February sown crop had significantly higher K, Zn and Cu content in stover compared to 3rd March sown. Total uptakes of N, P and Zn were higher with 3rd March sown crop compared 16th February crop. The uptake of N, P and Fe in grain was significantly higher with 3rd March sown crop as compared to 16th February sown crop. However, N, P, K and Zn uptake in stover was markedly higher with 3rd March sown crop. Further, 3rd March sown crop had significantly higher total N, P and Zn uptake than 16th March sown crop. Sorghum cultivars varied significantly in nutrient contents and uptake (N, P, K, S, Zn, Fe and Cu) in grain and stover except K content in grain. Total uptake of N was higher with CSH13, while total uptake of P was maximum with CSV27 and K with CSV23. With respect to the micronutrient, total uptake of Zn and Fe was higher with CSH13, while total uptake of Cu was maximum with CSV20. Hence, use of nutrient efficient cultivars like CSH13, CSH16, CSV27 and SPV 462 with optimum sowing time is necessary to improve nutrient-use efficiency of summer sorghum. Further, cultivar ‘SPV 462’ showed the higher photosynthetic rate (PN), stomatal conductance (gs) and intrinsic transpiration ratio as compared to other genotypes irrespective of the sowing dates.The micro-nutrient deficiency in human food and animal feed and fodder in rural areas could be addressed by selecting appropriate sorghum cultivars rich in micro-nutrient (Fe, Zn and Cu) contents in grain and stover.