Effect of planting pattern of two herbaceous forage legumes in fodder grasses on productivity of grass/legume mixture in semi-arid tropical kenya

摘要

An experiment was conducted to investigate the effect of planting pattern of legumes on the growth, persistence and productivity of grass/legume mixture in the semi-arid tropical Kenya. The legumes, Seca and Siratro were planted either as single or double rows between rows of Napier grass and giant panicum. Plant population, growth and productivity of the mixture were monitored for a period of 4 wet seasons; short rains (SR) 02, long rains (LR) 03, SR 03 and LR 04 and two dry seasons (DS) 03 and DS 04. There was significantly (P<0.05) more plants that survived from double rows of legumes (15 plants m-2) than from single rows (10 plants m-2). Legumes planted in double rows between grass rows covered more plot than when planted in single rows with Siratro covering more plot than Seca. However, legumes planted in double rows had no significant (P<0.05) dry matter (DM) yield advantage over single rows and did not benefit or impede growth (tiller and canopy cover) of the fodder grasses. The productivity of the associated fodder grasses was not affected and hence combined total DM yield (grasses + legumes) were not significantly different. Napier grass was more vigorous, had more tillers, large canopy and consequently was more productive than Panicum. On the basis of combined DM production, Napier grass/Seca was most productive while Napier intercropped with Siratro and Panicum intercropped with either Seca and Siratro showed similarity in DM. Seca was more productive than Siratro and overall the proportion of the legume to total DM was highest during the dry season than wet season. Dry matter was highest during the SR 02 and declined progressively with seasons and was lowest during the dry seasons.