Evaluation of an almond collection using morphological variables to choose superior trees

Introduction. Iranian almond germplasm is regarded as one of the most diverse and valuable genetics resources for almond improvement. Materials and methods. In the present study, 155 almond genotypes were evaluated to determine the overall degree of variation and to detect superior trees. The variation was observed for traits related to phenology, morphology, yield and fruit quality. Results and discussion. Nut and kernel traits contributed most of the total variation but there were also significant differences in flowering and ripening times. The majority of important correlations were determined between the characteristics representing nut size and kernel size. Cluster and principal component analyses confirmed considerable diversity in the studied germplasm. Conclusion. Genotypes MSh11, MSh100, MSh97, MSh24 and MSh126 were the best trees in terms of flowering season, consistently high fruit set, large nut and kernel size, and low percentage of double kernels. Furthermore, genotypes MSh9 and MSh110 were very late flowering and could be useful in breeding to improve flowering season of almond.