Abstract:
Rainwater harvesting is an old age practice used in water-scarce rainfed crop production areas. It is practiced to supplement additional water for crops with insufficient amounts of rainfall for optimum production. The aim of this study was to assess yield responses of Swiss chard under In-field rainwater harvesting techniques (IRWH) and catchment areas. The trials were conducted at two sites, University of Limpopo experimental farm (Syferkuil) and on farmer’s field at Apel. The main plots were two catchment areas (2 m (1 m runoff strip plus 1 m basin)) and (3 m (2 m runoff strip plus 1 m basin)), while the subplots were five IRWH techniques namely; Control (farmers practice), Rainfed, IRHW (without mulch + irrigation), IRWH+Mulch and IRWH+Mulch+Irrigation. The results obtained showed no significant differences in yield of Swiss chard in relation to catchment areas of 3 and 2 m respectively. However, significant differences in plant height, plant vigour, number of leaves and chlorophyll contents were obtained under different IRWH techniques. Significantly, highest average plant height of 40.75 cm was obtained in IRWH+Mulch compared to Rainfed with the lowest average 28.50 cm at Syferkuil. A similar trend was obtained at Apel. There were significant differences in number of leaves under IRWH techniques; the highest mean of 16.00 was obtained in the control (farmers practice) treatment, while the lowest mean of 9.00 was obtained in IRWH treatment at Apel. At Syferkuil, significantly highest average number of leaves was obtained in the IRWH+Mulch+irrigation treatment, while the lowest average number of leaves was obtained in the rainfed treatment. Regarding the yield of Swiss chard, the significantly highest average yield was obtained under IRWH+Mulch+irrigation and 3 m catchment treatment combination which was 84.86 t ha-1 compared to 20.66 t ha-1 in rainfed and 3 m catchment treatment combination at Syferkuil. Similar trend was found at Apel with the highest average yield recorded in IRWH+Mulch+irrigation treatment combination. Hence, IRWH technique with mulch and irrigation could be adopted by growers in a water-scarce environment like the Limpopo Province of South Africa.
