EFFECT OF TILLAGE PRACTICES AND OVER-SOWING METHODS ON GROWTH AND POPULATION DYNAMICS OF TWO STYLOSANTHES SPECIES IN NATURAL PASTURE

Abstract

This study was conducted to evaluate the growth and population dynamics of two legume species oversown into natural pasture. Two legumes (Stylosanthes guianensis cv. Cook and Stylosanthes hamata cv. Verano), two tillage methods (zero-tillage and minimal tillage) and two planting methods (broadcasting and drilling) were combined into eight (8) treatments and replicated 4 times as a 2 x 2 x 2 factorial arrangements in a randomized complete block design. Planting was carried out in late rainy season (September, 2013) and the components of the oversown natural pasture were evaluated for height and soil cover between 2-8 months after planting (MAP) which covered the dry and rainy seasons, There were no marked differences (p>0.05) in the heights of the sown legumes, other herbaceous species, sown legume cover and existing dominant grass (P. maximum) cover in the dry season. There were significant differences (p<0.05) in the height of existing dominant grass, soil covered by sown legumes and other herbaceous species in the dry season. There were no significant differences (p>0.05) in the heights and soil cover of the legumes, other herbaceous species, and existing dominant grass (P. maximum). The two Stylosanthes species tolerated the drought of dry season. Irrespective of the tillage or sowing methods employed, the two oversown legumes survived competition from companion or existing species over the growing seasons, perhaps through the initial clearing of the field prior to over-sowing activities.