Effects of cutting management and N-fertilizer application on plant height, tiller production and percentage dry matter in a run-down <i> Panicum maximum </i> 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. Grass swards were cut at intervals of 3, 6, 9 and 12 weeks and received 0, 150, 300 and 450 kg N/ha. Increasing the interval between harvests from 3 to 12 weeks increased plant height from 31.5 cm to 139.2 cm and from 25.2 cm to 72.6 cm in 2000 and 2001, respectively but reduced the number of grass tillers. The dry matter percentage increased from 28.0 to 35.4% with 9-weekly cut compared with 3-weekly interval in 2000 and increased from 23.6 to 32.9% with 12-weekly interval of cut compared with 9-weekly interval in 2001. Tiller number per square metre generally decreased with increase in cutting interval up to 9-weeks interval. Plant height and grass tiller number were increased with increase in N application. Plant height increased from 48.4 to 91.5 cm, or from 42.6 to 68.9 cm when fertilizer N was increased from 0 to 450 kg N/ha applications in 2000 and 2001, respectively. The dry matter percentage was decreased from 32.4 to 31.2% with incremental application of N from 150 to 450 kg N/ha in 2000 and decreased from 28.7 to 25.2% with 0 to 450 kg N/ha application in 2001. Plant height, tiller number and dry matter yields of crop fractions tended to pick up early in the season, increased with season and decreased at the late season. The dry matter percentage tended to increase with advancing season. Cutting of 12 weeks interval gave the highest plant height when combined with 450 kg N/ha while fertilizing at 450 kg N/ha produced the highest tiller number when combined with cutting at 6-weekly interval. Harvesting at 9-weekly interval gave the highest percentage dry matter when combined with 300 kg N/ha.

Keywords: Grass height, Tiller population, Dry matter content, Interval between cut, N – Fertilizer.

Agro-Science Vol.42 (2) 2005: pp. 28-33