Multivariate analysis of morphological and phenological traits in Camelina sativa (L.) Crantz for identification of promising accessions

Abstract

Camelina ( Camelina sativa L.) is a promising oilseed crop for semi-arid environments, but its productivity is constrained by genotype × environment interactions and complex trait interrelationships. This study evaluated 23 camelina accessions over two consecutive years under rainfed, semi-arid conditions to characterize phenological, morphological, and yield-related traits, estimate genetic parameters, and identify superior genotypes for breeding. Significant genotypic variation was observed across traits, with broad-sense heritability ranging from 13.2% for plant height to over 80% for thousand-seed weight, days to seeding initiation, and maturity ending. Genetic advance as percent of mean (GAM) indicated high selection potential for seed yield, thousand-seed weight, lateral branches, pods per plant, and reproductive traits, whereas low GAM was found for several phenological traits. Genotypic correlations revealed that seed yield was positively associated with branching intensity, crown diameter, pods per plant, and thousand-seed weight, while early flowering and compact growth tended to reduce yield, highlighting trade-offs between earliness and reproductive output. Principal component analysis (PCA) explained 65% and 63% of total variation in the first and second years, respectively, with the first component representing vegetative and reproductive growth, and the second capturing reproductive timing and seed traits. Subsequent components reflected yield performance, harvestability, and phenology. PCA-based graphical analysis and accession clustering identified four categories each year, with Categories III/C (moderate phenology, high reproductive traits) and IV/D (early-maturing, highly reproductive) consistently exhibiting superior seed yield and adaptability. Integration of PCA and genetic parameters allowed identification of key traits for selection and development of predictive frameworks for breeding. These findings indicate that early- to moderately-maturing camelina accessions, combining balanced vegetative growth and reproductive efficiency, achieve stable yields under water-limited conditions. Accessions in Categories III/C and IV/D represent promising genetic resources for breeding programs aimed at improving both seed yield and environmental adaptability. This study demonstrates the utility of combining multivariate analysis with genetic parameters to guide trait prioritization, selection indices, and ideotype-based breeding strategies in camelina for semi-arid cultivation.