Morphological, ecophysiological and photosynthetic diversity of some Pistacia species for use in breeding programs

Evaluation of genetic diversity is the basis of any breeding programs in all plants. The aim of this study was to evaluate and investigate the morphological, ecophysiological and photosynthetic diversity of some Pistacia species which can be used in breeding programs. A total of 42 genotypes belonging to Pistacia atlantica Desf., P. mutica Fischer & C. A. Meyer, Pistacia vera L., Pistacia terebinthus L. and P. khinjuk Stocks species were studied. The results showed that the P. terebinthus species is more efficient than other species in terms of leaf weight, chlorophyll a and b and total chlorophyll, as well as chlorophyll fluorescence and photosynthesis efficiency index. Among the varieties of pistachio belonged to P. vera, ‘Siirt’ and ‘Uzun’ cultivars had the highest levels of chlorophyll a, b, and total, photosynthesis rate and transpiration. In addition, P. mutica species had the highest leaf phenol content and stomatal conduction. For most traits measured, the lowest value was observed in P. atlantica species. Moreover, the results showed that there was a positive and significant correlation between morphological and photosynthetic traits as well as morphological and ecophysiological ones so that, the leaf length had a positive and significant correlation with the quantum yield of photosystem II (Fv/Fm) (r = 0.87), the efficiency index of photosynthesis (pi) (r = 0.76), total chlorophyll (r = 0.92), and carotenoid (r = 0.91). Cluster analysis divided the genotypes into three distinct groups. The first group consisted of P. vera species and its genotypes plus P. khinjuk species. The second group included the species of P. mutica and P. atlantica, and the third one just consisted of the species of P. terebinthus. In general, the results of this study showed that P. terebinthus specie, as well as ‘Akbari’ and ‘Siirt’ cultivars from P. vera can be used as parents in breeding programs to improve the rootstocks and cultivars resistant to environmental conditions.