Anatomical study on sound and cracking fruits of jujube '' Ziziphus mauritiana Lam".CV. Tufahi during growth and ripening

Abstract

This study was conducted on 10- years old jujube trees CV. Tufahi grown in Al- Hartha District , Basrah Governorate , to determine the time of crack initiation and changes in some anatomical characteristics of sound and cracking fruits during growth and ripening. Results showed that crack initiation occurred in pericarp tissue after 31 days of anthesis and continued to develop throughout the growth stages of the cracking fruits up to the ripening stage. Results also showed significant differences in some anatomical characters between sound and cracking fruit tissues , in which sound fruits had significant increases, over cracking fruits,in cuticle and epidermis layers thickness and number of cells per mm2 of the inner mesocarp layer recording values of 5.571 um and 34.86 and 271.3 cell respectively , whereas cracking fruits gave significant increases in cell length and width of the inner mesocarp as compared with sound fruits , recording values of 83.2 um and 104.1 um respectively. Anthesis period factor had significant influence on the studied characters, in which period 31 days of anthesis recorded the highest significant increases in cuticle and epidermis layers thickness and number of cells per m m2 over other anthesis periods, whereas period 141 days of anthesis gave the highest significant increases in cell length width as compared to other anthesis periods. The combination of sound fruit and period 31 days of anthesis had the highest significant increases in cuticle and epidermis layers thickness and number of cells per m m2, whereas cracking fruit and period 141 days of anthesis had the highest significant increases in cell length and width as compared to other anthesis periods. It was also found that the swelling length formed in pericarp layer tissue increased throughout fruit growth and ripening stages recording the highest significant increase of value at period 141 days of anthesis ( 340.51 um ) . In addition, both cracking length and width formed in pericarp layer tissue recorded the highest significant increases of value at period 141 days of anthesis , i.e . 262.56 um and 197.66 um respectively .