不同苹果矮化砧穗组合的抗旱性比较研究

Comparative Study on Drought Resistance of Different Apple Dwarfing Rootstock and Scion Combinations

以4年生苹果矮化砧穗组合(‘宫藤富士’/G935、‘宫藤富士’/M9-T337和‘宫藤富士’/SH6)为试验材料,研究了3种组合叶片形态结构的差异,并结合各组合在干旱胁迫8 d期间及复水7 d后的光合作用与生理生化指标的变化,利用隶属函数法综合评价其抗旱性。结果显示,‘宫藤富士’/SH6的叶片厚度、栅栏组织厚度及气孔密度均显著低于‘宫藤富士’/G935和‘宫藤富士’/M9-T337;干旱胁迫期间,与另外两个砧穗组合相比,‘宫藤富士’/SH6具有更高的水分利用效率(WUE)、渗透调节物质积累量、超氧化物歧化酶(SOD)活性和叶片ABA含量,而丙二醛(MDA)含量最低;就光合参数而言,‘宫藤富士’/SH6的净光合速率(P_(n))、蒸腾速率(T_(r))和气孔导度(G_(s))在干旱胁迫期间均显著低于‘宫藤富士’/G935和‘宫藤富士’/M9-T337。隶属函数分析结果表明,‘宫藤富士’/SH6抗旱性最优,其次为‘宫藤富士’/G935,而‘宫藤富士’/M9-T337抗旱性最差。综上,‘宫藤富士’/SH6是抗旱性优良的苹果矮化砧穗组合。

To evaluate the effect of apple dwarfing rootstocks on the scion growth and drought resistance,we used four-year-old apple trees with different scion-rootstock combinations(’Fuji’/G935,’Fuji’/M9-T337 and’Fuji’/SH6). Morphology analysis of these three apple trees showed that’Fuji’scion grown on SH6 exhibited significantly reduced leaf thickness,palisade tissue thickness and stomatal density compared with the’Fuji’grafted on G935 and M9-T337. Furthermore,three kinds of apple trees were exposed to drought stress treatment for determining their drought tolerance and recovery feature after re-watering. The analysis of drought-related physiology parameters indicated that compared with the other two grafted combinations,the’Fuji’/SH6 combination displayed enhanced water use efficiency(WUE),osmoregulation substance content,superoxide dismutase(SOD)activity and ABA content,and the reduced malondialdehyde(MDA)content,net photosynthetic rate(P_(n)),transpiration rate(T_(r))and stomatal conductance(G_(s))under drought stress. The results of membership function analysis showed that’Fuji’/SH6 had the optimal drought resistance,followed by’Fuji’/G935,and’Fuji’/M9-T337 had the worst drought resistance.Overall,’Fuji’/SH6 grafted combination showed excellent drought resistance.