Growth, yield, and biochemical behaviors of important stone fruits affected by plant genotype and environmental conditions.

• Three independent experiments on peach and nectarine cultivars and genotypes in Iran showed significant variations in growth, yield, and biochemical behaviors. • 'Henri' was found to have superior yield, tissue firmness, and total soluble solids. • Specific cultivars were found to have higher yield efficiency and nutrient levels compared to control cultivars, and the study recommends 'Flamino', 'Nectared', and 'Henri' as the best nectarine cultivars and 'Shasta', 'Sorkho-Sefid Mashhad', 'Suncrest', 'Fayette', and 'Shandabad-Hasteh-Joda' peaches as superior cultivars for specific locations. • These findings emphasize the importance of selecting appropriate cultivars for optimal growth and yield and continued research in stone fruit breeding. Stone fruit breeders face a significant challenge in obtaining new and high-yielding cultivars, and utilizing unknown ones. Among stone fruit, peaches and nectarines are the most prominent fruits. To address this issue, three independent experiments were conducted on various peach and nectarine cultivars and genotypes at two locations in Iran during 2018–2019 and 2019–2020 using a randomized complete block design with three replications. The results showed significant variations in growth, yield, and biochemical behaviors among the different genotypes and cultivars. 'Henri' was found to have superior yield, tissue firmness, and total soluble solids. Additionally, certain peach cultivars, such as 'Fayette', 'Sorkho-Sefid-Mashhad', and 'Shandabad', had higher yield efficiency than the control cultivar 'J.H. Hale'. Furthermore, 'PMsh-5′ had higher levels of ascorbic acid, antioxidant capacity, and carotenoids. 'Haj-Kazemi' had the tallest average tree height, trunk diameter, and crown of the tree in Golmakan, while 'Anjiri-Zaferani' had the highest levels of total soluble solids, flavor index, and pH. Based on these findings, 'Flamino', 'Nectared', and 'Henri' are recommended as the best nectarine cultivars in Mashhad due to their high pomological and phenological traits. 'Shasta', 'Sorkho-Sefid Mashhad', and 'Suncrest', as well as 'Fayette' and 'Shandabad-Hasteh-Joda' peaches, are recommended as superior cultivars for Mashhad and Golmakan, respectively. This study highlights the importance of selecting appropriate cultivars for optimal growth and yield and emphasizes the need for further research in stone fruit breeding. [ABSTRACT FROM AUTHOR]