Characterisation of grape genotypes collected from Western Uganda
Abstract
In Uganda, a number of exotic grapes genotypes were introduced by the British and are being grown; however, the lack of knowledge about their similarities and differences have hindered their utilization and commercialization. Field based trial was conducted to characterise the grape genotypes collected from Western Uganda. The objectives of the study were to determine variation in growth of grape genotypes, to determine variation in development of the grape genotypes and to determine variation in yield and quality of the grape genotypes. The plant materials used were grapevines from 4 genotypes collected from Western Uganda (Mbarara and Bushenyi districts). Management practices such as defoliation, mulching, pruning, dormex (hydrogen cyanamide) application, training, thinning, tipping off and irrigation were done. Data on number of spurs per plant and time to bud break were collected after pruning for two seasons, time to ripening data was collected at veraison for one season, data on fruit bunches per plant, bunch weight, number of fruits per bunch, fruit weight and total soluble solids were collected at harvest for the first season only. Collected data were subjected analysis of variance (one-way and two-way) using R software version 4.3.1. Analysis indicated that interactions between genotypes and seasons had significant difference in time to bud break but not in number of spurs per plant. Time to ripening, number of fruits per bunch, fruit weight and total soluble solids varied significantly among the grape genotypes. Number of spurs per plant, fruit bunches per plant and bunch weight did no vary significantly among the grape genotypes. Genotype 4 took the shortest time to break buds and to ripen, genotype 1 had the highest amount of fruits in a bunch, genotype 2 had the highest fruit weight and genotype 3 had the highest total soluble solids. In overall evaluation, diversity existed among the grape genotypes studied, genotype 4 was identified different from the rest of the genotypes with regards to development and quality. It is recommended that principal component analysis, further studies on improvement of total soluble solids, morphological and genetic variations among genotypes of grapes should be done.