Optimizing In-Vitro Conservation and Rapid Multiplication Regimes for Exotic and Local Taro Genotypes

ABSTRACT

Taro (Colocasia esculenta (L) Schott) is an important staple food crop grown throughout many part of the world for it fleshy corms and nutritious leaves. Suckers are the main planting materials used in West Africa; therefore, it is traditionally conserved in field collections. This is not an effective conservation strategy for medium to long term preservation of taro genetic resources due to extreme climatic conditions, pests and diseases. Tissue culture is one of the invitro techniques which have in recent years become major agricultural importance in the area of plant propagation, disease elimination and production of secondary metabolites in-vitro. However, with tissue or micropropagation conservation, challenges include: High growth rate of both the local and exotic genotypes of taro which causes sub-culturing in every eight weeks and also high shoot proliferation and all axillary buds produce shoots, leading to a dense population competing for limited nutrients in the glass vessel. Taro is a crop that is amenable to tissue culture. A study was conducted to optimize rapid multiplication and establish slow growth systems for Colocasia genotypes in-vitro. Thus, taro genotypes used for the experiment were obtained from the Taro Breeding Programme at Crop Research Institute which includes SA0 002, CE/MAL/32, SA0 006 and CE/MAL/ 14, BL/SM/80, KA 019 as corms. The study was carried out at the Tissue culture labouratory-Crops Research Institute (CRI), Fumesua.  The experiment was categorized into 5 stages thus: In-vitro Rapid Multiplication, In-vitro Medium-Term Conservation; In-vitro Recovery, Fourier Transform Infra-red analysis for concentration of Mannitol absorption content in Colocasia genotype and Biochemical analyses. The genotypes were evaluated in a complete random design. Means were separated using LSD at 5%. Rapid multiplication experiment cultures were maintained at 25±10C at 16hr photoperiod.