Abstract:
Soil tillage has influence on soil conditions and rhizosphere, ultimately influencing growth and productivity of plants. The objectives of this study were to (i) determine the effects of ridge-furrow on the physiology and growth of spring wheat, (ii) determine the effect of ridge-furrow planting on kernel yield and yield components and (iii) to determine the effect of ridge-furrow on root growth and soil physical characteristics. This experiment was conducted at Egerton University (0o 22’ 26’’ S, 35o 56’ 1.3’’ E) and Kenya agricultural and livestock research organization, Njoro (0° 22′ 47’’ S, 35° 56′ 1.7’’ E) in a randomized complete block design (RCBD) as a split-plot arrangement. Tillage systems served as the main plot and cultivars (Kwale and Kingbird) as the sub-plot. Location had a significant (p≤0.05, p≤0.01 and p≤0.001) effect on (ear emergence, flowering, maturity, flag leaf senescence, plant height. Yield, 1000 kernel weight, spike length, number of spikelets, chlorophyll, NDVI and soil traits (temperature, electrical conductivity, and bulk density). Tillage system was significant (p≤0.001) for ear emergence, flowering, maturity, flag leaf senescence, plant height, yield, 1000 kernel weight, spike length, harvest index, kernels per spike, number of spikelets and chlorophyll content. Cultivar Kwale and Kingbird were significantly (p≤0.05) different for all the traits. The ridge system had higher means for yield (2.22 tonnes ha-1) than the flat system (1.35 tonnes ha-1). Cultivars in the ridge system took 4 days longer to flowering and heading and 7 days longer to maturity and flag leaf senescence than the cultivars in the flat tillage system. Yield significantly correlated (r=0.76*) with thousand kernel weight and the number of seeds spike-1 (r=0.73*). Soil bulk density negatively correlated to root length (r=-0.78*), root surface area (r=81*), root diameter (r=-0.27) and root volume (r=-0.68). Soil moisture positively associated with root length (r=0.80*) and root surface area (r=0.76*). This study has shown that ridge tillage system improved wheat roots and plant growth, kernel yield and yield components. Therefore, the approach could be implemented for wheat cultivation in Kenya.
