砧木断根对西瓜嫁接苗生长和光合特性的影响

Effects of root-pruning splice grafting on the growth and photosynthetic characteristics of watermelon grafting seedlings

为探究砧木断根对西瓜嫁接苗生长和光合特性的影响,以西瓜品种早佳(8424)为接穗,南瓜品种砧壮为砧木,采用单子叶贴接法嫁接,设置砧木不断根(CK)和砧木断根(DRC)2个处理进行研究。结果表明,与CK相比,砧木断根使西瓜嫁接苗株高降低,茎叶干质量、叶柄长和叶面积均表现为先低于对照、后高于对照的趋势,在嫁接后24 d,砧木断根处理的西瓜嫁接苗的叶柄长、第1片真叶叶面积、第2片真叶叶面积和茎叶干质量分别比对照增大了11.40%、33.34%、11.46%和25.02%。与CK相比,砧木断根使西瓜嫁接苗的叶片净光合速率、胞间二氧化碳浓度、蒸腾速率和气孔导度显著增大;光合产物可溶性糖和淀粉含量都在嫁接后18 d显著升高。由此可见,断根嫁接苗对西瓜嫁接苗后期的生长和光合能力的提高有促进作用。

In order to investigate the effects of root-pruning splice grafting on the growth and photosynthetic characteristics of watermelon grafted seedlings,the watermelon variety Zaojia(8424)was used as scion and the pumpkin variety Zhen-zhuang was used as rootstock.The difference between the root-pruning splice grafting(DRC)and common root intact splice grafting(CK)was studied.The results indicated that the DRC grafting method improved the growth of watermelon seedling at the late stage after grafting.Compared with CK,the length of leaf petiole,the area of first true leaf,the area of second true leaf and the shoot dry mass were increased 11.40%,33.34%,11.46%and 25.02%at 24 days after grating,respectively.The net photosynthetic rate,intercellular carbon dioxide concentration,transpiration rateand stomatal conduc-tance of leaves were significantly increased after grafting.The soluble sugar and starch content of photosynthetic products increased significantly at 18 days after grating.It can be seen that root-pruning splice grafting can promote the growth and photosynthesis of watermelon grafted seedlings.