金冠/中砧1号苹果树耐低铁胁迫的评价

Evaluation of Golden Delicious/Chistock 1 on Resistance to Low Iron Stress

为了对苹果砧木‘中砧1号’耐低铁能力进行评价,本研究以金冠/山荆子为对照,设正常供铁(40μmol·L-1)和低铁胁迫(0、4、10、20和30μmol·L-1),着重研究2年生金冠/中砧1号的形态以及生理生化指标的变化。研究表明,金冠/中砧1号在30μmol·L-1 Fe时,叶片未出现黄化,且新梢增长量、叶面积以及幼叶叶绿素含量、活性铁含量、光合速率与正常铁处理植株无显著差异;0~20μmol·L-1Fe水平下,虽然出现黄化现象,但是其各项指标受影响程度均低于金冠/山荆子。金冠/山荆子在30μmol·L-1 Fe下15 d严重黄化;0~20μmol·L-1 Fe水平下在秋梢生长期出现了严重的小叶焦梢现象。表明在金冠长期低铁环境下,用中砧1号作砧木能耐30μmol·L-1低铁胁迫且生长发育基本正常。

In order to evaluate the capacity of Chistock 1 on resistance to low iron stress,this experiment was conducted on the phenotypic,physiological and biochemical characteristics of 2-year-old Golden Delicious/Chistock 1(GD/Cs)under different iron conditions of 0,4,10,20,30 or 40 μmol · L-1 Fe-EDTA. Compared to Golden Delicious/Malus baccata(GD/Mb),GD/Cs at 30 μmol · L-1 Fe showed no chlorosis in the whole growth period,and had no significant differences at Fe levels between the normal concentration(40 μmol · L-1)and low Fe stress(30 μmol · L-1)on shoot growth,leaf area,young leaf chlorophyll,photosynthetic rate,or active iron content. Furthermore,at 0 to 20 μmol · L-1 Fe,GD/Cs showed much slighter chlorosis than GD/Mb. However,GD/Mb showed severe chlorosis after 15 days at 30 μmol · L-1 Fe,and reduced leaf area with shoot tip dieback from 0 to 20 μmol · L-1 Fe in autumn growth stage. Thus,the experiment lead a preliminary conclusion that Golden Delicious can grow normally under long-term low iron stress on rootstock of Chistock 1.