不同砧木枝接‘元林’核桃愈合过程扫描电镜观察

Scanning Electron Microscope(SEM)Observation of the Healing Process of Yuanlin Walnuts Grafted with Different Rootstocks

【目的】通过对核桃枝接愈伤组织形成过程的显微观察,为选择适宜的砧木、提高核桃嫁接成活率和苗木质量提供科学依据。【方法】以‘香玲’‘黑核桃’‘鸡爪绵’和‘枫杨’的实生苗为砧木,采用枝接的方法分别嫁接‘元林’核桃品种后,利用扫描电镜观察不同砧穗结合体愈伤细胞和愈伤组织的形成过程。【结果】‘香玲’核桃、‘黑核桃’和‘枫杨’砧木分别嫁接‘元林’后,第20天发现愈伤组织细胞,而‘鸡爪绵’核桃砧木嫁接‘元林’后第10天已经发现有愈伤组织,第30天后不同砧穗结合部位均产生大量的愈伤组织。枝接后第30天,接穗萌芽新梢开始快速生长。【结论】‘鸡爪绵’核桃砧木与‘元林’核桃愈合能力较强,扫描电镜观察枝接后第10天到第30天是愈伤组织产生期,为嫁接管理的关键时期。

[Objective]Through microscopic observation of the formation process of walnut grafting callus,scientific basis could be provided for selecting suitable rootstock types,improving the survival rate of walnut grafting and the quality of seedlings.[Method]The seedlings of‘Black walnut’‘Jizhaomian’‘Xiangling’and‘Pterocarya stenoptera’were used as rootstocks to be grafted with‘Yuanlin’walnut,respectively.Then the formation process of different callus cells and tissues after being grafted was observed by scanning electron microscope.[Result]Callus cells were found on the 20th day after‘Xiangling’‘Black Walnut’and‘Pterocarya stenoptera’rootstocks were grafted with‘Yuanlin’walnut,but calluses were found on the 10th day after‘Jizhaomian’rootstocks were grafted with‘Yuanlin’walnut.Also,a large number of calluses were produced at all joints of rootstocks and ears after being grafted for 30 days,the scion sprouted and new shoots began to grow rapidly.[Conclusion]‘Jizhaomian’was a good rootstock to be grafted with‘Yuanlin’walnut,and their joints had strong healing ability.The critical period of the grafting management occurred in the callus span from 10th day to 30th day after being grafted.