evaluation of proline, proteins and sugar during phonological processes of flower buds of commercial pistachio cultivars

abstract the present research was done to evaluate proline, proteins and sugars of flower buds of pistachio trees during phonological stages. this study was conducted using a split-plot design with three replications considered time as main factor (5 stages) and cultivars (ahmad-aghaee, ouhadi, kaleh-ghochi and akbari) as secondary factor. the experiment was conducted at ferdowsi university of mashhad and institute of pistachio research of iran (pri). the studied variables included proline, soluble sugars and total protein which were assessed during rest (winter), flowering (beginning of spring) and after spring frost. the highest (27.36 mili mol/gram weight of fresh flower bud) and lowest (7.86 mili mol/gram weight of fresh flower bud) rates of proline were found in ahmad-aghaee after chilling injury and bud swelling, respectively. the highest rate of total protein was shown by akbari (70.79%) and ouhadi (71.25%) at flower burst, and the lowest amount was obtained at bud swelling of ouhadi (25.39%). results indicated that sugars accumulated during winter and reduced by beginning of spring. amount of proline increased during flowering and after spring frost. overall proteins were fixed and low after falling leaves (autumn) to bud dormancy (winter), but its amounts increased after bud dormancy till after flowering and spring frost