Melia volkensii (Gürke) is being increasingly promoted as an on-farm tree in Kenya. Researchers’ and farmers’ views on its competitiveness with crops differ; research station studies have found it to be highly competitive whereas farmers do not consider it to be so. Because of difficulties in seed germination, it is probable that dissemination programmes will rely upon plants produced from root and stem cuttings, rather than on seedlings. This study evaluates differences in root system architecture of plants raised from seed (of four provenances), stem or root cuttings and the relationships between the competitivity index (CI) and crop yield. Cuttings were more shallowly rooting than seedlings, and had higher competitivity indices, and there was a negative relationship between CI and crop yield. No differences in root architecture between provenances were found. Therefore, to reduce tree-crop competition, the use of seedlings rather than cuttings should be recommended when promoting the use of this species on dryland farms. If cuttings are used to circumvent the problems of seed germination, alternative methods of controlling competition, such as root pruning, need to be considered.
Tag: propagation
A decision support tool for propagating miombo indigenous fruit trees of southern Africa
Indigenous fruit trees (IFTs) contribute to the livelihoods of rural households as sources of food, income and medicine. Conservation and domestication of IFTs involve germplasm selection, collection, multiplication and evaluation. In addition, biodiversity and genetic improvements have been realized through propagation. However, there are numerous challenges when propagating indigenous trees and the choice of appropriate propagation techniques determines the success of domestication programme. In this paper we synthesize different propagation methods used for indigenous fruit trees, and propose a decision support tool based on desirable attributes of individual IFT, technical requirements, expertise of the propagators and relative cost of implementing the technology in addition to field performance and tree management. Depending on circumstances, this decision support tool can be used to quickly choose a propagation method for a given fruit tree so as to maximize on germplasm collection, multiplication and evaluation without compromising field performance and management of the fruit trees.