永嘉早香柚果实裂瓣规律与授粉调控

Study on the effect of hand pollination on juice sac cracking of Yongjia Zaoxiangyou pomelo cultivar

以9年生的土柚砧永嘉早香柚为试材,研究了人工授粉及未授粉永嘉早香柚果实的裂瓣及中心柱发育规律。结果表明,未授粉果实的裂瓣于盛花后105d及其后的1个月内发生并结束,异花授粉果实的裂瓣指数不及未授粉果实的1/10,开始裂瓣的时期也比未授粉处理推迟15d。果实裂瓣与果实的快速膨大具有同步性和相关性。裂瓣指数与中心柱开裂指数的相关系数高达0.973,与中心柱横径呈显著负相关。未授粉果实中心柱发育不充实,直径仅为授粉果实的56%,并在后期出现中空现象,囊瓣与中心柱粘连不紧密,从而导致囊瓣开裂;授粉果实通过促进中心柱发育控制裂瓣发生。

Experiment was conducted with 9-year-old trees of Yongjia Zaoxiangyou pomelo cultivar （Citrus grandis L.） Osbeck） grafted on rootstock of local common pomelo seedlings for studying the effect of hand pollination on fruit juice sac cracking and central vascular axis. Results showed that the juice sac cracking of the hand-pollinated fruit were well controlled. The juice sac cracking of the non-hand pollinated fruit started from 105 d after full blossom and aggravated in next 30 d, while that of hand pollinated fruit started half a month later and with a cracking index less than 1/10 of non-hand poUinated fruit. A close correlation and synchronization was observed between juice sac cracking and rapid enlargement of fruit. The cracking index of juice sac was high positively correlated to the cracking index of central vascular axis, with a correlation coefficient as high as 0.97, and high negatively to the diameter of the central vascular axis. The central vascular axis of non-hand pollinated fruit was not well developed, with a diameter only 56 % of hand pollinated ones, and cracked then hollowed at later stage of fruit development, which resulted in poor adhesion of juice sacs to the central vascular axis and finally cracking of juice sacs. Hand pollination greatly inhibited juice sac cracking by stimulating the development of the central vascular axis.