Status of conservation of the indigenous leaf vegetables and fruits of Africa

The diversity of indigenous leaf vegetables and fruits of Africa is being seriously eroded as a result of multiplicity of environmental, political and socio-economic factors. This paper discusses some new development-related and crises factors that have interacted in concert to amplify the spate of loss of the indigenous leaf vegetables and fruits genetic resources in Africa. The paper also suggests urgent steps that nations individually and Africa in general can take to arrest the wave of loss of plant genetic resources and therefore ensure the conservation of our remaining indigenous leaf vegetables and fruits heritage

Review - Application of biotechnological for the improvement of Nigerian indigenous leaf vegetables

Nigeria is endowed with many indigenous leaf vegetables (ILVs) species, which spread across the estimated cultivable land area of 71.2 million hectares. These ILVs provide food, income, employment and herbal medicine to the population. Uncollected and uncharacterized germplasm, pests, diseases, anti-nutritional factors, recalcitrant seed, seed dormancy and perishable produce militate against the realization of potentials of the ILVs. This paper discusses biotechnological applications such as meristem culture, in vitro selection, zygotic embryo culture, somatic embryo genesis, protoplast culture, anther culture and genetic engineering that can solve improvement and production problems associated with some selected ILVs. Among the problems envisaged in the application of these biotechnological techniques are lacks of resources, selections of crop for research, attitude of government and weather conditions

A Cassava vein mosaic virus promoter cassette induces high and stable gene expression in clonally propagated transgenic cassava (Manihot esculenta Crantz)

The study described a T-DNA vectorwith a Cassava veinmosaic virus promoter cassette (pCsVMV) and a kanamycin selectable marker gene driven by the 35S Cauliflower mosaic virus promoter with a view to stably express transgenes over repeated cycles of clonal propagation. A ?-glucuronidase reporter gene under control of pCsVMV (pCsVMV-GUS) was introduced into the cassava landrace ‘Tokunbo’ via Agrobacterium-mediated genetic transformation. Transgenic tobacco plants (Nicotiana tabacumSR1) with the same gene construct were also produced. In tobacco, the pCsVMV-GUS was highly expressed in all tissues tested such as leaf, stem, petiole, and roots. In transgenic cassava, the pCsVMV-GUS gene was highly expressed in all tissues and most cell types of in vitro plants including leaf, stem, petiole, and fibrous roots. The pCsVMV-GUS gene was also highly expressed in these tissues as well as in tubers of greenhouse grown cassava. High and stable pCsVMV-GUS gene expression wasmaintained over 3 cycles of ratooning under greenhouse conditions, thus showing the absence of undesired gene silencing effects after repeated in vitro subculturing and vegetative propagation. Fromthe high constitutive levels of GUS activity observed, the study concluded that the CsVMV promoter cassette was useful for high-level expression in cassava over repeated cycles of clonal propagationThe study described a T-DNA vectorwith a Cassava veinmosaic virus promoter cassette (pCsVMV) and a kanamycin selectable marker gene driven by the 35S Cauliflower mosaic virus promoter with a view to stably express transgenes over repeated cycles of clonal propagation. A ?-glucuronidase reporter gene under control of pCsVMV (pCsVMV-GUS) was introduced into the cassava landrace ‘Tokunbo’ via Agrobacterium-mediated genetic transformation. Transgenic tobacco plants (Nicotiana tabacumSR1) with the same gene construct were also produced. In tobacco, the pCsVMV-GUS was highly expressed in all tissues tested such as leaf, stem, petiole, and roots. In transgenic cassava, the pCsVMV-GUS gene was highly expressed in all tissues and most cell types of in vitro plants including leaf, stem, petiole, and fibrous roots. The pCsVMV-GUS gene was also highly expressed in these tissues as well as in tubers of greenhouse grown cassava. High and stable pCsVMV-GUS gene expression wasmaintained over 3 cycles of ratooning under greenhouse conditions, thus showing the absence of undesired gene silencing effects after repeated in vitro subculturing and vegetative propagation. Fromthe high constitutive levels of GUS activity observed, the study concluded that the CsVMV promoter cassette was useful for high-level expression in cassava over repeated cycles of clonal propagatio