Comparison of leaf stomatal features in some local and foreign apricot (Prunus armeniaca L.) genotypes

The objective of this study was to determine the leaf stomatal features of some local and foreign apricot (Prunus armeniaca L.) cultivars. Stomata frequency, size and stomatal conductance of leaves of twenty apricot genotypes from inside and outside of Turkey were measured. The leaf stomatal frequency significantly varied among the apricot cultivars. The highest leaf stomata frequency was found in cv. Orange Red (349 stomata/mm(2)) and lowest was in cv. Cnef (182.2 stomata/mm(2)). Mean stomata size was 81.8 m. In 2006 stomatal conductance was the lowest (84 mmol m(-2) s(-1)) in 'Roxana' and the highest (263 mmol m(-2) s(-1)) in 'Thyrinthe' cultivars. In 2007, the lowest stomatal conductance (143 mmol m(-2) s(-1)) was found in 'Hasanbey' cultivar and the highest (405 mmol m(-2) s(-1)) was in 'Cnef' cultivar. Generally in the second year counductance values were higher which was probably due to higher values of maximum air temperature. The differences in leaf stomatal conductance values that existed among the genotypes can be taken into consideration as selection criteria for apricots to be grown in regions with higher summer temperatures.