Certain physiological changes during growth and development of Fruits of Jujube Ziziphus spp. cvs . Tufahi and Bambawi

Abstract

The present study was carried out in a private orchard in Al-Hartha, region, Basrah, during the growing season of 2010 / 2011, to investigate changes in certain physiological (Fresh weight of whole fruit , activity of Invertase and cellulose , as well as changes in soluble proteins and total Free amino acids} during growth and development of fruit of jujube cvs. Bambawi and Tufahi . A completely randomized block design was used with three replicates. The data were subjected to the analysis of variance and revised LSD at 5% was used to compare mean values. The results , may be summarized as follows:- The results indicated that jujube fruits of both cultivars displayed a double sigmoidal growth curve , with lag period of fruit growth was shorter ( 4 weeks ) for the cv. Tufahi , whereas for fruits of cv. Bambawi , it was 6 weeks . The results showed that fresh weight for Tufahi fruits were higher than those for the Bambawi fruits . The pattern of Invertase was similar in fruits of both cultivars , as the activity was low during early stages of fruit development , but the activity of Invertase increased as the fruit advanced toward ripening , and then the activity declined as fruits entered an over ripe stage . For cellulase , the activity was high and reached earlier for Tufahi fruits as compared to its activity in Bambawi fruits . However , the activity of cellulase in fruits of both cultivars declined rapidly as the fruits entered an over ripe stage .The level, of total free amino acids was high during early stages of fruits growth of both cultivars , and increased until it reached its highest value during the 10th and 12th week from fruit set in fruits of Tufahi and Bambawi respectively. However, the levels of free amino acids declined rapidly as the fruits advanced toward an over ripe stage. As for soluble proteins, the levels was low during early stage of fruit development, but the levels increased as the fruit advanced in development , reaching its highest levels during the 12th and 14th week from fruit set in Bambawi and Tufahi fruits respectively. Thereafter, the levels of soluble proteins declined as the fruit entered the ripening phase.