Introduction
Peach is among the most important fruit trees cultivated in Iran since ancient times. Thus, evaluating adaptability and identifying optimal peach varieties is crucial for its cultivation expansion. The ability of a peach cultivar (a specific cultivated variety of peach) to adapt to a new environment depends on several factors, including climate, soil as well as disease and pest resistance. Understanding these factors is crucial for the successful introduction of peach cultivars to new areas. Researchers and growers are constantly working to develop new cultivars, evaluate existing cultivars and refine agricultural practices. By considering cultivar adaptability and implementing appropriate strategies, growers can expand peach cultivation into new regions, increasing fruit production and diversifying the agricultural landscape.
 Materials and Methods
The present study was conducted with 15 peach varieties to evaluate their adaptability for a period of three years starting from 2016 at Urban Orchard Research Station in Kermanshah Province. The trees were planted Within a randomized complete block design (RCBD) with three replications Spaced 4*4 m apart in March 2014 Four trees were planted in each experimental unit, and a total of 12 trees were evaluated for each variety. To evaluate the pomological and yield characteristics of the cultivars, various fruit traits were measured over a three-year period from 2016 to 2018. These traits included fruit and stone weight, fruit and stone dimensions, stone-to-flesh adhesion, skin and flesh color, percent soluble solids, pH, fruit acidity, tree yield, yield efficiency, ripening time, and ripening duration. At the onset of fruit color change, the total number of fruits on each tree was recorded. Upon ripening, all fruits of each cultivar were harvested and weighed. A 30-fruit sample was then selected to determine weight, flesh content, stone weight, and fruit quality parameters, including soluble solids, pH, and titratable acidity. To assess quality traits, juice was first prepared from five ripe fruits. Soluble solids were measured using a handheld refractometer model [refractometer model]. pH was measured using a pH meter model [pH meter model]. Titratable acidity was determined by titration with 0.1 N NaOH solution in the presence of phenolphthalein indicator until a color change to purple was observed. The amount of NaOH consumed indicated the malic acid content per 100 g of fruit, which is the predominant acid in peach and nectarine fruits. The collected data were analyzed using the MSTATC software, and mean comparisons were performed using Duncan's multiple range test.
Results and Discussion
The results revealed significant differences between the varieties under study in terms of various fruit characteristics, including the number of fruits per tree, fruit weight, fruit and stone dimensions, fruit yield per tree and hectare, and fruit quality characteristics such as soluble solids, pH, and titratable acidity. The average yield over three years indicated that the fruit yield per hectare varied among the varieties from about 5.5 tons per hectare to about 38 tons per hectare. The 'Suncrest' variety enjoyed the highest yield with over 35 tons per hectare. Other varieties such as 'Federica', 'Babygold 6', and 'Babygold 7' were also superior with over 25 tons of fruit per hectare. Based on their good yield, fruit weight, and fruit quality, the varieties 'Suncrest', 'Federica', 'DixiRed', 'Domiziana', 'J.H. Hale', 'Amipsimidia', 'Alberta', 'Spring Crest', and 'Anjiry' were found to be suitable for fresh consumption. For industrial purposes, the varieties 'Babygold 7', 'Babygold 6', and 'Sudanl' were found to be appropriate due to their fruit quality and very high yield. As the results indicate, the yield rate increased as the peach trees aged. Moreover, the yield was recorded to be very high in some cultivars at the age of five, yet lower in some cultivars due to genetic differences or in response to the observed environmental conditions.
 Conclusion
This study provides valuable insights into the selection of suitable peach varieties for cultivation in Iran, considering both fresh market and industrial process applications. The findings can guide farmers and policymakers in optimizing peach production and enhancing the competitiveness of the Iranian fruit industry.