干旱胁迫下不同砧木对酿酒葡萄‘Syrah’光合作用的影响

Effects of Different Rootstocks on Photosynthesis of Wine Grape ‘Syrah’ Under Drought Stress

为探讨干旱胁迫下不同砧木对酿酒葡萄‘Syrah’光合作用的影响,以‘Syrah’为试材,研究了干旱胁迫下嫁接苗(采用‘Beta’‘5BB’‘SO4’为砧木)和自根苗叶片叶绿素含量(叶绿素a,Chl a;叶绿素b,Chl b;叶绿素总量,Chl)、光合效率(净光合速率,Pn;气孔导度,Gs;蒸腾速率,Tr;水分利用效率,WUE)和PSⅡ光化学活性(PSⅡ最大光化学效率,Fv/Fm;光化学猝灭系数,qP)各项指标的动态变化。结果表明:1)干旱胁迫下,嫁接苗和自根苗的各项指标除WUE呈现先上升后下降,整体上升的趋势外,其它均呈下降趋势。说明干旱胁迫下,嫁接苗和自根苗光合效率和光合能力都有所降低;2)但与自根苗相比,嫁接苗中除Tr外其它指标均高于自根苗,尤其在干旱胁迫严重时,嫁接苗的Chl a、Chl b、Chl、Gs、Pn、WUE均显著高于自根苗,说明干旱胁迫下嫁接苗具有较高的光合效率和光合能力;3)3种嫁接苗中,又以‘Beta’为砧木的嫁接苗各项指标表现更为突出,优于‘5BB’和‘SO4’为砧木的嫁接苗,说明以‘Beta’为砧木的‘Syrah’嫁接苗在干旱胁迫下具有更高的光合效率和光合能力。因此,优先推荐‘Beta’作为抗旱节水酿酒葡萄‘Syrah’的理想砧木。

In order to study the effects of different rootstocks on photosynthesis of wine grape‘Syrah’under drought stress,the experiment was conducted with‘Syrah’grapevine grafted on different rootstocks(‘Beta’‘5 BB’and‘SO4’)and its self-rooted seedling as the test material.The effect of self-rooted seedling and different rootstocks on the chlorophyll content(chlorophyll a,Chl a;chlorophyll b,Chl b;total chlorophyll,Chl),photosynthetic efficiency(net photosynthetic rate,Pn;stomatal conductance,Gs;transpiration rate,Tr;water utilization efficiency,WUE),photochemical activity of PSⅡ(PSⅡmaximal photochemical efficiency,Fv/Fm;photochemical quenching coefficient,qP)under drought stress were studied.The results showed that,1)Under drought stress,the indexes of grafted seedlings and self-rooted seedlings showed a downward trend except WUE increased first and then decreased,it showed upward trend in overall,which indicated that photosynthetic efficiency and photosynthetic capacity of grafted and self-rooted seedlings Gs decreased under drought stress;2)But compared with self-root seedlings,all the indexes except Tr in grafted seedlings were higher than those in self-root seedlings.Especially when drought stress is severe,the various parameters of Chl a,Chl b,Chl,Gs,Pn and WUE of grafted seedlings Gs were significantly higher than those of selfrooted seedlings,indicating that grafted seedlings Gs had higher photosynthetic efficiency and photosynthetic capacity under drought stress;3)Considering‘Syrah’grafted on‘Beta’had higher photosynthetic efficiency and photosynthetic capacity under drought stress,so‘Beta’were considered as optimum rootstocks for‘Syrah’grape,followed by‘5 BB’and‘SO4’.Therefore,priority was given to‘Beta’as an ideal rootstock of drought-resistant and water-saving wine grape‘Syrah’.