A Quantitative Genetic Approach to Avocado Breeding Value Estimation
Venkata Rao
*
Department of Fruit Science, College of Horticulture, UHS Campus, GKVK, Bengaluru, India.
Venkatesha S C
Regional Horticulture Research and Extension Centre, UHS Campus, GKVK Post, Bengaluru-560065, India.
Priyanka Hugar
Department of Fruit Science, College of Horticulture, UHS Campus, GKVK, Bengaluru, India.
*Author to whom correspondence should be addressed.
Abstract
The avocado one of demanding fruit crop for its immense nutritive value and diabatic suitable fruit. But improvement in the crop is limited. Hence, improving its genotypes is crucial due to rising avocado demand in India, low local yields, and the need to develop superior, climate-adapted genotypes. In present study, Statistical analysis, including genotypic (GCV) and phenotypic (PCV) coefficients of variation, showed that a wide genetic diversity exists within the collected germplasm, particularly for key traits like fruit yield, fruit volume, average fruit weight, pulp weight, seed weight, and pulp to seed ratio (GCV/PCV all above 20% and GCV for pulp to seed ratio at 55.61%). Heritability estimates revealed that most characters, including fat content (99.67%) and total soluble solids (98.54%), exhibited very high heritability, indicating strong genetic control and suitability for direct selection. The analysis of genetic advance (GA) and genetic gain (GG) identified traits offering the best potential for next-generation improvement. The Pulp to seed ratio stood out with an exceptional 110.08%. GG, projecting a massive proportional increase in edible pulp through selection. Other traits with high heritability coupled with high genetic advance, such as fruit volume (213.65 ml GA, 87.30% GG), fruit yield (80.96 Kg GA, 75.66% GG), and average fruit weight (195.54 g GA, 66.29% GG), are considered parameters of high selection value. Conversely, traits like non-reducing sugars showed minimal absolute genetic advance (0.08% GA). These findings confirm the existence of substantial genetic variability among the collected ecotypes, particularly in Kodagu and Mysuru regions, and provide breeders with reliable metrics to select superior germplasm based on Pulp to seed ratio, Fruit volume, Fruit yield, Average fruit weight, and Number of fruits for accelerated progress in avocado improvement.
Keywords: Genetic variability, heritability, Genetic Advance (GA), Genetic Gain (GG), direct selection