Production potential of sweet sorghum (Sorghum bicolor) for biomass, grain yield and bio-fuel under variable nutrient environment in north-west India

Abstract

A field experiment was conducted at the fodder research farm of the Punjab Agricultural University, Ludhiana, during the rainy (kharif) seasons of 2019 and 2020, to assess the relative performance of sweet sorghum [Sorghum bicolor (L.) Moench] genotypes under different fertility levels. Three sweet sorghum genotypes tested were: ‘SPV 2530’, ‘CSV 19SS’ and ‘CSV 24SS’ at 3 fertility levels, i.e. 60 : 30 : 30, 80 : 40 : 40 and 100 : 50 : 50 kg N : P₂ O₅ : K₂ O/ha. All the treatment combinations were replicated thrice in a factorial randomized block design. The variations in terms of growth and ethanol yield were observed among 3 genotypes, with the sweet sorghum genotype ‘CSV 19SS’ having the best performance, especially in ethanol yield and gave significantly highest potential ethanol yield of 1,490 L/ha. The application of 100 : 50 : 50 kg N:P:K/ha resulted in the best growth response and recorded significantly maximum ethanol yield of 1,417 L/ha. However, fertilizer rate as low as 80 : 40 : 40 kg N : P : K/ha produced potential ethanol yield which was statistically at par as produced with the highest fertility level. Hence, 80 : 40 : 40 kg N : P : K/ha would also result in reasonable performance of the crop in the areas of this study, especially under favourable environmental conditions.