Rooting Patterns and the Effect of Sesbania species on Soil Moisture Content

Abstract

This study was conducted at ICRAF field station in Machakos, Kenya. It was designed to examine the effect of three Sesbania species on soil moisture content and to test their rooting patterns. For each of the Sesbania species, free growth (roots and shade present), guy-wiring (shade removed) and root barrier (roots removed) treatments were used. The Sesbania species, with these treatments, were intercropped with maize. Sole maize was used as control. The treatments were arranged in a randomized complete block design with ten treatments and three replications. In each plot, a single row of Sesbania was planted at 0.5 within-row spacing. Six maize rows were planted at 0.3m within-row spacing and 0.75 m between-row spacing. Soil moisture content was monitored in Sesbania sesban and sole maize treatments. The root length density was studied in guy-wiring treatments of S. sesban and S. macrantha. The number of roots in the profile wall was studied in the free growth treatment of the three species. The results indicated that soil moisture content was lower in rows near trees compared with those far from trees. The study of the root system indicated that Sesbania sesban has higher root length density than S. macrantha. It is concluded that roots of the studied species can compete with agricultural crops for moisture and nutrients.