PHENOTYPIC DIVERSITY ANALYSIS OF ETHIOPIAN HOT PEPPER (Capsicum annum L.) ACCESSIONS FOR POD AND QUALITATIVE TRAITS

Abstract

Diverse environmental conditions and variation in farming systems are expected as a base for wide variability in hot pepper germplasm in Ethiopia. Forty-eight accessions were collected  from different agro-ecological zones of Ethiopia where hot pepper is extensively produced and high phenotypic diversity is expected to exist (Meskan, Mareko, Halaba,, Hawassa and Abishege, Asossa , Bale, West Hararghe) and one standard cultivar (Mareko Fana) were used for this study. Therefore, this research was conducted to estimate phenotypic diversity of 49 genotypes for qualitative and fruit quality related traits. Data for qualitative and fruit quality related traits were subjected to analyses of variance separately. The frequency distribution of the genotypes displayed high polymorphism for all traits except for anthocyanins on the stem, leaf colour and dry fruit colour. Moreover, the diversity for qualitative traits was ranging from 0.65 to 0.98 with an overall average Shanon diversity index of 0.88. The highest diversity index was obtained from calyx attachment (98%), anthocyanins on the fruit, canopy and fruit shape, followed by growth habit and fruit shape at blossom end (93%). The Shanon diversity index of H’ of within (88%) and between (12%) regions of collections were obtained, where anthocyanins on the fruit, green fruit color, fruit shape at blossom end and canopy shape and growth habit contributed very high for differentiation between regions of collections. The Principal Component Analysis (PCA) of fruit quality traits showed 55% of the total variance encountered by the first two components in which, fruit volume and surface area, TSS%, pedicel length were associated with the first components, while only fruit shape index were associated with the second component. The cluster analysis using fruit quality traits, the genotypes were distinctly grouped into six clusters with similarity value ranging from 0.15 to 1.27 and inter cluster D² values of 13 to159, with the maximum distance recorded between IV and V (159) and III and V (158) clusters. Therefore, this study demonstrated the existence of high phenotypic diversity among genotypes for qualitative and fruit quality related traits in Ethiopian collections that could be properly conserved and exploited for future variety improvement program.