Leaf color chart based nitrogen management in spring rice

Abstract

A field experiment on LCC-based nitrogen (N) management was carried out at Rajapur, Bardiya during the spring season of 2021 to determine the growth and productivity of spring rice varieties. The experiment was laid out in strip plot design with three replications. The treatment consisted of four varieties (Chaite-5, Hardinath-1, Hardinath 1-F1, and Hardinath-3) in horizontal plots and five levels of LCC-based N management practices (Pure LCC, 25% N (basal) + LCC, Recommended dose of fertilizer in three splits, Farmer’s dose, and no nitrogen (i.e. Control) in vertical plots. The results showed that Pure LCC-based nitrogen management produced the highest grain yield (6.24 t ha^-1) followed by 25% N basal + LCC (5.77 t ha^-1). LCCbased treatments produced a significantly higher yield than recommended dose applied in three splits. The higher yield in pure LCC was because of higher yield attributes like effective tillers m^-2, higher thousand-grain weight, lower sterility percentage, longer panicle length, and higher panicle weight. Hardinath-3 and Hardinath 1-F1 with pure LCC produced significantly higher yields than other treatment combinations. The spring rice varieties Hardinath 1-F1 and Hardinath-3 were high yielders than Hardinath-1 and Chaite-5. The higher yield of Hardinath-3 was due to higher number of effective tillers m^-2, longer panicle length, and higher panicle weight. Similarly, the higher yield of Hardinath 1-F1 was mainly due to higher thousandgrain weight and higher number of effective tillers m^-2 as compared to other varieties except for Hardinath-3. The nitrogen use was highest in Hardinath1-F1 (116.25 kg ha^-1) followed by Hardinath-3 (108.75 kg ha^-1). The varieties Hardinath 1-F1 and Hardinath-3 with pure LCC-based N management were high-yielders in Bardiya-like climatic conditions.