Determination of optimum population density Of basil (ocimum basilicum l.) For intercropping With hot green pepper (capsicum annum l.) At Hawassa, southern Ethiopia

Abstract

Hot pepper (Capsicum annum L.), its green pod and Basil (Ocimum basilicum L.) are widely grown in Hawassa area by smallholder farmers as a mixed cropping system with different population densities of basil. Hence, an experiment was conducted in a field at Hawassa Green Mark Herbs Private Limited Company site to determine optimum basil population densities for intercropping with hot pepper and assess yield advantage and economic returns. Two hot pepper varieties (Melka Shote and Melka Awaze) and four basil population densities (100% (55556), 75% (41667), 50% (27778) and 25% (13889) plant ha-1 ) and their soles as check were factorialy arranged and laid out in randomized complete block design with three replications. Data on phenology, growth, yield components, yields and quality parameters were collected for both crops and analyzed using SAS software (version 9.3). The analysis of variance revealed that the green hot pepper yield was not significantly (P≤0.05) influenced by variety. However, the highest marketable fruit yield (8.05 t ha-1 ) was obtained from a plot with the lowest population density of basil (25%). Similarly, the sole cropping system of green hot pepper had the highest yield (8.58 t ha-1 ) and intercropping with basil reduced its yield by 23 %. On the other hand, the interaction was not significant (P≤0.05) for fresh leaf yield and essential oil yields of basil. However, the highest fresh leaf yield of basil (8.92 t ha-1 , 6.24 t ha-1 and 12.02 t ha-1 ) was obtained from Melka Awaze variety, 100% density and sole cropping system, respectively. The essential oil yield of basil was not influenced by hot pepper varieties, but significant higher mean essential oil yields of (14.73 kg ha-1 and 19.46 kg ha-1 ) were obtained from 100% density, which was statistically at par with 75%, and the intercropped system of basil, respectively. Intercropping of Melka Awaze variety with 50% density of basil resulted in the maximum total LER value of 1.86 and MAI value of 251,525 ETB ha-1 , Whereas intercropping of Melka Shote with 50%, 75% and 25% population densities had maximum total LER values of 1.78, 1.74 and 1.74, and MAI values of 240,755 ETB ha-1 , 242,385 ETB ha-1 and 236,808 ETB ha-1 , respectively. Furthermore, correlation analysis showed that growth and yield components had significant and positive contribution to the yields of both crops. Therefore, the population density of 27778 basil plants ha-1 with Melka Awaze variety and 41667 basil plants ha-1 with Melka Shote variety could be recommended to the targeted area. However, further studies across locations, seasons, under both rainfed condition and full irrigation systems, and for dry pod of hot pepper would be important to assess the yield and economic advantages of intercropping hot pepper with basil and come up with a more compressive conclusion.