Experimental studies on seed production of tropical grasses in Kenya. 2. Tillering and heading in seed crops of eight grasses.

Abstract

Tillering in seed crops grown undisturbed for 6 months was studied over 2 years in cultivars of Setaria sphacelata, Chloris gayana, Panicum coloratum, Panicum maximum and Brachiaria ruziziensis. Tiller numbers rose to a maximum around the time of initial head emergence (5-10 heads/m2), followed by a decline and finally a levelling off. Head emergence was found to continue in some cv. for over 3 months. The weight/tiller increased at a linear rate. Tiller numbers never exceeded 1900/m2. Tillers were less numerous but were heavier in the year of sowing than in the subsequent year. Total dry weights of tillers were also highest in the first year. Seed yield was significantly correlated with degree of concentrated head emergence and percentage of heading tillers in a cultivar. It is suggested that, within cv., plants with heavier tillers may produce higher seed yields. Cv. within species can be identified according to date of initial head emergence. A type of culm branching is described in which tillers develop into flowering culms out of elevated nodes of erect parental culms. (Abstract retrieved from CAB Abstracts by CABI’s permission)