Herbage leaf to stem ratio and yield distribution of ime as influenced by cutting frequency and N-fertilizer application in an old run-down Panicum maximum pasture

Abstract

In a sandy loam soil at Nsukka, the effects of cutting management and fertilizer-N treatment on revitalization of a run-down pasture were investigated in 2000 and 2001. Increasing the interval between cuts from 3 to 12 weeks increased the proportion of stem relative to leaf blade in the grass herbage in the second year. The proportion of leaf to stem at 3-weekly interval of cuts was 54.6:1; this ratio had fallen to 13.3:1 at 6 weeks, 4.7:1 at 9 weeks and 7:1 at the 12 weekly cutting intervals. Incremental application of fertilizer N led to increase in the proportion of stem relative to the leaf blade in the grass herbage. The proportion of leaf to stem when N was not applied was 12.7:1; this ratio had fallen to 11:1 at 150kg ha^-1, 7.7:1 at 300kg ha^-1 and 6.9:1 at the highest N-rate of 450kg ha^-1. The 6-week interval of cuts yielded significantly higher dry matter of grass herbage than the 3 - weekly intervals in most of the periods considered. Grass herbage yield picked up early in the year and increased with advancing season up to about early October and then decreased in both years. Increasing the interval between harvests from 3 to 6 weeks increased the dry matter yields of leaf, stem and inflorescence in all the periods considered. Fertilizer-N treatment significantly increased grass herbage yield in most of the periods. A combination of 6 - weekly interval of cuts with 450kg ha^-1 gave the highest forage grass herbage dry matter yield.

Keywords: Leaf to stem ratio, Yield distribution, Cutting Frequency, N – Fertilizer

Agro-Science Vol. 4 (1) 2005: pp. 74-77