Influence of Nitrogen Fertilization on Quality Parameters and Heat Use Efficiency of Basmati Rice

Physical, milling, cooking, and chemical qualities of basmati cultivars had great concern for researchers, producers, traders, and consumers as instability index of production is higher. Quality may be enhanced by good N optimization to responsive basmati varieties. Therefore, a field experiment was conducted for two consecutive years under split-plot design. Results revealed that application of 120 kg N ha−1 improved heat use efficiency (4.85 & 4.91 kg ha−1 degree-day−1), milling quality traits, physical quality, and chemical quality while aroma score (up to 2.50) improved only up to 60 kg N ha−1. Highest protein (7.79 & 7.77%) and least amylose (21.88 & 22.24%) content were recorded with highest N rates while highest protein yield (414.18 & 402.66 Kg ha−1) reported at 120 Kg N ha−1. Basmati varieties, HUBR 10–9 and HUBR 2–1, were superior in most of quality traits along heat use efficiency (4.62–4.70 kg ha−1 degree-day−1). However, short-grained aromatic variety HUR 917 recorded higher head rice recovery (64.34 & 63.21%), protein (7.61 & 7.63%), and amylose content over others. Most important trait, i.e. aroma (1.83–2.38) score, was higher with basmati varieties. Overall, basmati (HUBR 10–9 and HUBR 2–1) grown with 120 kg N ha−1 proved superiority. This study achieved better heat use efficiency along with improved quality of basmati rice which found to be positively correlated with most quality traits of basmati rice. The low amylose in basmati is preferable, and amylose found to be negatively correlated with heat use efficiency.