Response of leaf area ratio, specific leaf weight, grain moisture content and quality traits of spring maize (Zea mays L.) to nitrogen dose and application timing

Abstract

A field experiment was conducted at Regional Research Station, Uchani, Karnal of CCS Haryana Agricultural University during two consecutive spring seasons. The study aimed to assess the response of leaf area ratio (LAR), specific leaf weight (SLW), grain moisture content and quality traits of spring maize (Zea mays L.) to nitrogen dose and application timing. The experiment comprised four nitrogen doses, N1 (150 kg N ha-1), N2 (165 kg N ha-1), N3 (180 kg N ha-1) and N4 (195 kg N ha-1) assigned to main plots, and four nitrogen application timing were allocated to subplots, S1 (50% at sowing + 25% at 8-leaf stage + 25% at tassel initiation), S2 (25% at sowing + 25% at 4-leaf + 25% at 8-leaf + 25% at silking), S3 (20% at sowing + 30% at 6-leaf + 40% at flowering + 10% at grain formation) and S4 (20% at 2-leaf + 30% at 6-leaf + 40% at tassel initiation + 10% at grain formation). The treatments were arranged in a strip plot design with three replications. The results indicated that LAR and SLW significantly influenced by different nitrogen doses at all growth stages except at 25 DAS during both years. The highest LAR and SLW values were recorded with N1, which was statistically at par with N2 but significantly higher than N3 and N4. Among the nitrogen application timing, S3 produced the highest LAR and SLW followed by S4 and it was higher than S1 and S2. Grain moisture content increased with increasing nitrogen doses, with the highest moisture content observed under N4 (21.34 and 21.17%), which was similar with N3 and lowest under N1 (18.73 and 19.01%) during both the years. In nitrogen application timing, maximum grain moisture content was recorded under S3 (21.22 and 21.52%) and S4 (20.43 and 20.80%), while S1 resulted in the lowest moisture content. Quality traits including lysine, tryptophan and protein content were significantly affected by nitrogen dose and application timing. The highest lysine (2.93 and 2.84%), tryptophan (0.75 and 0.74%) and protein content (10.02 and 9.83%) were obtained with N4, which was statistically similar to N3 but significantly superior to N1 and N2 during both years. Among the nitrogen application timing, treatment of S4 recorded the highest lysine (2.89 and 2.83%), tryptophan (0.75 and 0.74%) and protein content (9.81 and 9.64%), which was statistically at par with S3 but significantly higher than S1 and S2.