Genetic parameters and correlation studies for fruit and seed characteristics in half-sib progenies of Cinnamomum zeylanicum Blume

Abstract

Cinnamomum zeylanicum Blume is an economically important tree spice valued for its bark, leaves and increasingly for its fruits. The present study was undertaken to assess genetic variability, heritability and inter-relationships among fruit and seed traits in half-sib progenies of C. zeylanicum under humid tropical conditions of the Western Ghats, India. Six-year-old half-sib progenies representing five seed sources were evaluated during 2023-2025 in a randomized complete block design. Genetic parameters including genotypic and phenotypic coefficients of variation, heritability and genetic advance were estimated, along with genotypic and phenotypic correlations among traits. Substantial variability was observed for most fruit and seed characters. Fruit traits such as mature fruit length (84.58%), fruit width (60.26%) and test weight (69.92%) exhibited high heritability coupled with moderate genetic gain, indicating predominance of additive gene action and suitability for direct selection. Seed length (81.33%) and seed dry weight (73.72%) recorded high heritability and moderate genetic gain, suggesting strong genetic control and potential for improving seed quality and vigour. Traits related to fruit number and fruit set showed greater environmental influence and lower selection efficiency. Correlation analysis revealed strong positive associations among size and weight-related fruit traits, as well as among seed morphological traits, indicating that selection for one trait could lead to simultaneous improvement of related characters. The study identifies key selection traits for cinnamon improvement and provides valuable insights for breeding, conservation and sustainable cultivation of C. zeylanicum.