樊庆琦 隋新霞 黄承彦 崔德周 李永波 楚秀生

摘要：为考察铁营养元素对普通小麦苗期生长发育的影响，以保存的86份山东省1950年以来搜集、引进和育成的小麦品种为研究对象，在缺铁胁迫下营养液培养15 d，考察根系数量、主根系长度、根干重、地上部分干重和根冠比与正常培养（对照）的关系以及不同年代供试品种的演变规律。结果表明，除根系长度外，其余4个性状缺铁胁迫下与对照相比，差异达极显著水平；根系数量、根系长度和地上部分干重品种间差异也达极显著水平。对上述性状进行方差分析和胁迫指数分析发现，多数小麦品种在缺铁胁迫下表现为根系数量减少，根干重和根冠比增加，地上部分干重明显降低。研究还发现，临麦4号、潍麦8号和山农27等小麦品种具有较强的缺铁耐受能力，可用于小麦铁营养高效的遗传改良。

关键词：小麦；苗期；缺铁胁迫；根系；胁迫指数

中图分类号：S512.101文献标识号：A文章编号：1001-4942（2018）05-0028-06

Abstract In order to investigate the effect of iron nutrition on growth and development of common wheat at seedling stage， 86 wheat germplasms from Shandong Province under normal culture and iron deficiency treatment were used as material to study the number of roots， length of main root， dry weight of root， dry weight of shoot and root/shoot ratio. Their evolution rules of different times were also studied. The results showed that except root length， the other 4 traits were significantly different between iron deficiency and control treatments. The root number， root length and dry weight of shoots were also significantly different between varieties. Furthermore， the variance and stress index analyses were performed， and the results indicated that most wheat varieties showed decrease in root number and shoot dry weight and increase in root dry weight and root/shoot ratio under iron deficiency treatment. This study also found that the wheat varieties such as Linmai 4， Weimai 8 and Shannong 27 had strong iron tolerance， so they could be used for genetic improvement of wheat iron nutrition.

Keywords Wheat； Seedling stage； Iron deficiency stress； Roots；Stress index

根系是小麥吸收生长发育必需矿物元素的器官。铁作为小麦必需的微量营养元素，具有重要的生物学功能。它参与叶绿素的合成，影响叶绿体的构造，是合成叶绿素的先决条件[1]。缺铁将导致细胞膜系统和胞内细胞器的畸变或破坏[2-4]，表型上则表现为黄化失绿现象[5]。另外，铁还具有参与作物呼吸作用和生物固氮等重要生物学功能[6-9]。

铁的供给水平和存在形式同样影响小麦根系的发育。铁浓度增加，可促进根系生长、根长和根重增加，但铁供给过量，则会导致毒害，抑制其生长[10，11]。……