Population Distribution of Wild Radish (Raphanus Raphanistrum L.) Weed and Soil Depth of Seed Bank Across Different Land-Use Types in Horro District, Western Oromia, Ethiopia

Abstract

Background: Wild radish (Raphanus raphanistrum L.) is an invasive weed in Ethiopia and hurting different land use types in the Horro district of the study area and fact, more research has not been done yet on the weed is highly infested and persisted for three decades. Therefore, this study was conducted to assess the weeds flora and seed bank status across different land use types in the Horro district of western Oromia, Ethiopia. Three locations and from each location five different land use were purposively selected and a 1m2 area of quadratic sampling techniques was used to record weed flora. From each quadrat, soil samples were taken having two soil depth levels (0-15cm and >15-30cm) to evaluate the soil seed bank of weeds. Results: The data of wild radish weed in different location and different land use types both field survey and greenhouse experiments were found a statistically significant difference (p<0.05) among the target action of land use types but there was found no significant difference among soil depths. More all less, the highest wild radish population was recorded from grazing land land followed by wheat crop land and among the locations, Gitilo Dale has the highest weed density. Among the weed flora, again wild radish was highly dominated weed species than the other weed species in all land use types and locations. From soil seed bank status of soil depth, high weed population was recorded at 0-16cm of second season weed emergence from pot and Gitilo Dale was the highest infected location at this season, while barley crop land was the highest infected among land use types in first season of weed emergence from pot. Among the weed species were recorded from soil depth, again wild radish was highly dominated in both seasons. The population of weed flora per quadrat was directly proportion with population recorded from soil depth that emerged from pot. Conclusions: This study has highly verified that this area has highly infected by wald radish (Raphanus raphanistrum) and there could be a source of weed seed. Generally, the concerned bodies should have to be given attention which should need immediate intervention strategies to mitigate the negative impacts of weed otherwise the area will be out of production soon. Therefore, an extensive integrated weed management strategies should be applied in all phases of cropping systems to sustain environment and reduce this weed in the future.