Effect of phosphorus and potassium on fodder production, quality and nutrient uptake of Lucerne.

摘要

A study was conducted in the main Forage Research Station Farm of Anand Agricultural University, Anand, Gujarat, India, during the winter, kharif and summer seasons of 2003 and 2004, to investigate the response of lucerne (Medicago sativa varieties GAUL-1 and AL-3) to phosphorus and potassium levels in terms of growth, fodder production, quality and nutrient uptake. The treatments were 2 levels of P (50 and 75 kg/ha P< sub>2O< sub>5) and 3 levels of K (50, 150 and 300 kg/ha K< sub>2O). Sowing of lucerne was carried out in the second week of December 2003, and the first cut was obtained after two months of sowing and subsequent cuts at an interval of 25 to 30 days. The last cut was done during third week of December 2004. The results showed significant increase in average plant height of lucerne with increasing levels of potassium. The maximum plant height was recorded in 300 kg/ha K< sub>2O, whereas the minimum in 50 kg/ha K< sub>2O. Cumulative green forage (GF), dry matter (DM) and crude protein (CP) yields of 19 cuts were not significant due to the lucerne varieties. The highest total uptake of N was recorded at a higher K dose (300 kg/ha K< sub>2O) and it was 17.8 and 11.9 higher than that of 50 and 150 kg/ha K< sub>2O, respectively. The effects of K levels irrespective of varieties on GF yield were significant at 300 kg/ha K< sub>2O to AL-3 over the treatments except application of 300 kg/ha K< sub>2O to variety GAUL-1. The effect of cuts irrespective of lucerne variety was significant for GF yield of lucerne. The effect of cut irrespective of potassium levels was significant for GF and DM yield of lucerne on pooled basis. Maximum total returns and net return over control was recorded when soil K dose applied at 300 kg/ha K< sub>2O during first year and 225 kg/ha K< sub>2O during second year irrespective of lucerne variety.