Performance of wheat (Triticum aestivum L.) genotypes on different levels of nitrogen at Khumaltar, Nepal

Abstract To evaluate the performance of wheat genotypes under different nitrogen doses, a field trial was conducted at the Nepal Agricultural Research Council (NARC), Khumaltar, Lalitpur. Two genotypes (NL1330 and WK1204) were combined with six nitrogen doses (50, 75, 100, 125, 150, and 175 kg/ha) in a split-plot design. NL1330 outperformed WK1204 in plant height, normalized difference vegetation index (NDVI), and tillers/m 2 , except for the soil plant analysis development ( SPAD) value. Higher nitrogen doses significantly increased all growth parameters. Phenological parameters such as days to 90% flowering, heading, and physiological maturity were observed to be minimum (110, 114, and 156 days, respectively) in NL1330. Maximum values of yield and yield attributes, such as spike length (9.96 cm), effective tillers/m 2 (514.26), grains/spike (47.09), grain yield (7.82 Mt/ha), and biological yield (18.42 Mt/ha), were observed in NL1330 compared to WK1204. Nitrogen doses also had a significant influence on yield and yield parameters, with maximum values of effective tillers/m 2 (484.87), spike length (9.97 cm), thousand grain weight (49.97 g), and biological yield (18.20 Mt/ha) observed at a nitrogen dose of 175 kg/ha. However, grain per spike (47.31) was maximum at a nitrogen dose of 150 kg/ha. Considering the parameters of grain yield, the nitrogen doses of 150 kg/ha and 175 kg/ha were on par for various yield attributes. Genotype NL1330 and a nitrogen dose of 150 kg/ha could be the better option to enhance the productivity of wheat in the lowland of Nepal.