青钱柳嫁接愈合过程中砧穗生理特性及其与亲和性的关系

Variations in physiological characteristics of rootstock-scion and its relationship to graft compatibility during the grafting union process of Cyclocarya paliurus

【目的】采用不同砧木嫁接青钱柳,分析不同嫁接组合接穗和砧木生理指标的差异,探讨砧穗生理特性与嫁接成活的关系,为青钱柳砧穗嫁接亲和性的早期预测和砧木选择奠定基础。【方法】分别以枫杨(F)、薄壳山核桃(B)和青钱柳(Q)作为砧木嫁接青钱柳接穗(3种嫁接组合),采用切接的方法进行嫁接,测定嫁接后0、40、70 d各嫁接组合砧木和接穗的可溶性糖、可溶性蛋白、淀粉及单宁含量、过氧化物酶(POD)和多酚氧化酶(PPO)活性,并统计嫁接70 d后的成活率。【结果】青钱柳本砧嫁接成活率为53.49%,显著高于以枫杨和薄壳山核桃为砧木的嫁接组合。嫁接后随着时间的延长,本砧嫁接砧穗中的可溶性糖和淀粉含量均呈现先降低后升高的变化规律;3个嫁接组合单宁含量均表现为先升高后降低趋势,但本砧嫁接组合在两个时段均最低,QB组合均最高;3个嫁接组合砧穗POD活性均表现为先升后降;本砧嫁接砧穗PPO活性先降后升,而QF和QB组合砧穗PPO活性均持续升高。相关分析表明,40 d时测定的砧穗可溶性糖、淀粉、单宁含量及PPO活性与嫁接成活率呈显著负相关(P<0.05),而POD活性与嫁接成活率呈显著正相关(P<0.05);70 d时测定的砧穗可溶性糖、单宁含量和PPO活性与嫁接成活率呈显著负相关(P<0.05),但接穗的POD活性与嫁接成活率呈极显著正相关(P<0.01)。接穗与砧木的PPO和POD活性差值绝对值分别在40和70 d时与嫁接成活率均呈显著负相关(P<0.05)。【结论】青钱柳本砧嫁接亲和性较强,而以枫杨和薄壳山核桃为砧木亲和性较弱,可溶性糖、淀粉、单宁含量、POD和PPO活性,以及POD和PPO活性差值绝对值可以作为青钱柳嫁接亲和性的早期评价指标。

【Objective】Variations in physiological indexes between scions and rootstocks of different grafting combinations were analyzed in Cyclocarya paliurus,and the relationship between the physiological characteristics of rootstocks and grafting survival was studied.This will allow the early prediction of grafting compatibility of rootstock-scion and the selection of C.paliurus stock.【Method】Three grafting combinations were designed,with Pterocarya stenoptera,Carya illinoinensis and C.paliurus as rootstocks to graft C.paliurus(as scions).The contents of soluble sugar,soluble protein,starch and tannin,peroxidase(POD)and polyphenol oxidase(PPO)activity in rootstocks and scions of the grafting combinations were measured at 0,40 and 70 days after grafting,respectively,while the grafting survival was determined at 70 days after grafting.【Result】The graft survival rate with C.paliurus as the rootstock was 53.49%,which was significantly higher than that of the P.stenoptera and C.illinoinensis grafting combinations.With the increase in time after grafting,soluble sugar and starch in the rootstock-scion initially decreased and then rose.The tannin content increased initially and then decreased,and the higher content of tannin in the rootstock-scion was not conducive to the survival of grafting.The increase in POD activity was beneficial for improving the defense response of affinity grafts,while a high PPO activity was not conducive to the survival of grafting.The correlation analysis showed that the soluble sugar,starch,tannin content,and PPO activity of stocks measured at 40 days were significantly negatively correlated with the graft survival rate(P<0.05),while POD activity was significantly positively correlated with the graft survival rate(P<0.05).The soluble sugar,tannin content,and PPO activity of the stocks measured at 70 days were significantly negatively correlated with the graft survival rate(P<0.05),but the POD activity of the scion was significantly positively correlated with the graft survival rate(P<0.01).The absolute value of the PPO activity difference between the scion and rootstock showed a significant negative correlation with the graft survival rate at 40 days(P<0.05),while the absolute value of the POD activity difference at 70 days showed a very significant negative correlation with the graft survival rate(P<0.01).【Conclusion】The graft compatibility was strong using C.paliurus as a grafting stock,while the grafting compatibility was weak when P.stenoptera and C.illinoensis were used as rootstocks.The content of soluble sugar,starch,tannin content,POD and PPO activity,and the absolute value of POD and PPO activity can be used as physiological indicators for the early evaluation of the grafting compatibility of rootstock and scion.