Evaluation of yield and economic advantage of Intercropping roselle with different planting densities Of common bean at hawassa, southern Ethiopia

Abstract

Roselle (Hibiscus sabdarif a L.) is a medicinal plant grown for its calyx yield. But, its cultivation in Ethiopia is not as common as that of other crops due to lack of appropriate cropping system. This experiment was therefore, conducted at Hawassa, southern Ethiopia, during 2017/2018 dry season to evaluate the performance of roselle and determine best intercropping combination of roselle with common bean for better economic yield, monetary advantage, and weed suppression. The experiment was carried out in a RCBD with a a 2x4 factorial arrangement and consisted of three replications and 11 treatments (sole cropping of two roselle varieties (Hibiscus-Sudan and Hibiscus-Jamaica) and a common bean variety (Ibbado) and intercropping of the roselle varieties with four common bean planting densities combinations (25%, 50%, 75%, and 100%)). All data collected were subjected to analysis of variance using SAS software version 9.3. Dif erences between means were assessed using Duncan`s Multiple Range Test at 5% probability level. Results of the experiment showed that the interaction between the main factors were nonsignificant for all parameters. However, the dif erence between the two roselle varieties was significant for all parameters evaluated in this experiment. Hibiscus-Jamaica took more days to flowering and maturity (145 and 180, respectively) and it was superior all parameters, except for thousand seed weight. Common bean planting density significantly influenced roselle seed yield per plant and dry calyx yield per hectare. Seed yields of roselle intercropped with 25% (46.6g) and 50% (47.05g) were statistically similar to that of 75% (40.65g) and 100% (39.27g) common bean planting densities. Dry calyx yield of roselle was higher at 25% (0.88 t ha -1) and lower at 100% planting density (0.74 t ha -1). Intercropping reduced roselle seed yield per plant by 16.62% and dry calyx yield per hectare by 12.1%. Hibiscus-Jamaica significantly reduced common bean maturity period and all yield and yield components, except 1000 seed weight. While number of pods per plant and seed number per pod showed decreasing trend, seed and biomass yields per hectare increased as planting density increased from 25% to 100%. Common bean planting density and cropping system significantly af ected weed infestation. The highest values for visual estimate weed ground coverage, weed density, and weed dry biomass were recorded for 25% planting density (2, 15.43 plant/m2 , and 13.34g/m2 respectively) and for sole cropping (2.5, 17.21 plant/m2 , and 15.61g/m2 respectively). Land equivalent ratio (LER) of Common bean was highest when intercropped with Hibiscus-Sudan (0.51) than with Hibiscus-Jamaica (0.38). Both roselle variety and common bean planting density did not influence total LER and monetary advantage index (MAI). However, higher yield and monetary advantages were obtained with variety Hibiscus-Sudan variety (35% and 17,946 ETB) and for 100% planting density (39% and 21,410 ETB) which was also ef ective in weed control. Therefore, intercropping Hibiscus-Sudan with a 100% planting density of common bean was recommended for growers in the same agroecology with the study area for better yield and economic advantage as well as for better weed control. Since this study was conducted during the dry season at one location, it should be repeated under rainfed condition at dif erent locations and in dif erent years.