Genetic Diversity and Grouping of Litchi Genotypes Based on 83 Qualitative and Quantitative Traits

The presence of a narrow genetic base is the major bottleneck in improvements in litchi to get desired objectives. Studies on the nature and extent of genetic diversity are directly related to yield and quality, which can be used in a breeding programme for genetic improvement. In the present study, 30 litchi genotypes were assessed with respect to variability, heritability and genetic advance based on 39 quantitative traits. Results revealed that phenotypic coefficients were lower than their corresponding genotypic coefficients suggesting an inherent relationship among them. High phenotypic and genotypic coefficients of variation were recorded for flavonoids in seeds (132.39 and 132.38%), flavonoids in the pericarp (116.89 and 116.86%), phenolics in the pericarp (97.84 and 97.83%), anthocyanin in the pericarp (55.73 and 55.54%), female flowers (53.08 and 52.98%), total chlorophyll (51.07 and 50.99%), phenolics in seeds (48.60 and 48.58%), number of fruits per cluster (44.94 and 44.73%), tree volume (38.80 and 38.70%) and panicle length (28.15 and 19.92%). Broad-sense heritability was more than 80% for all the traits except trunk girth, leaflet width, panicle length and titratable acidity. Heritability and genetic advance were found to be maximum for female flowers (%), phenolics and flavonoids content. A high coefficient of variation was observed for female flowers (%), number of fruits per cluster, phenolics and flavonoids. The grouping of genotype based on combined qualitative and quantitative traits presented more accurate results. This will help to select distant diverse genotypes in the hybridization programme in order to get more diverse progenies.