摘要
以耐碱性燕麦品种Vao-9和碱敏感性品种白燕5号为试验材料,采用盆栽法,用25、50、75和100 mmol L–1碱浓度(Na2CO3和NaHCO3按摩尔比1∶1混合)进行短期(14 d)和长期(28 d)胁迫处理,观测两品种根、茎、叶中Na+、K+、Ca2+、Mg2+吸收及分配特点,并从离子平衡吸收与分配角度,探讨燕麦对碱胁迫的生理适应机制。胁迫处理14 d后,燕麦体内Na+增加,K+下降,Ca2+和Mg2+变化不大,且两品种间各器官中4种离子的分配比例差异不显著。胁迫处理28 d后,两品种各器官中Na+增幅较大,K+、Ca2+和Mg2+降幅较大。Vao-9植株体内Na+、Ca2+含量大于白燕5号,但K+、Mg2+含量与白燕5号无显著差异,但两品种间各器官中4种离子的分配特点不同;当胁迫浓度达到100 mmol L–1时,与白燕5号相比,Vao-9叶片中少分配5.9个百分点Na+,多分配13.5个百分点K+、28.9个百分点Ca2+、10.9个百分点Mg2+,茎中多分配5.4个百分点Na+,少分配9.8个百分点K+,根中少分配28.9个百分点Ca2+、10.9个百分点Mg2+,因而Vao-9叶片中Na+/K+、Na+/Ca2+、Na+/Mg2+值较白燕5号低。可见,燕麦通过提高阳离子选择吸收及器官分配能力以适应碱胁迫。
In a pot experiment, an alkali-tolerant oat variety, Vao-9, and an alkali-sensitive variety, Baiyan 5, were exposed to 25, 50, 75, and 100 mmol L-t of alkali stress （molar ratio of Na2CO3：NaHCO3 = 1：1）. The contents of Na^＋, K^＋, Ca^2＋, and Mg^2＋ ab- sorbed by oat seedling and their distribution characteristics in root, stem, and leaf were measured after a short-term （14 d） or a long-term （28 d） stress treatment. The objective was to understand the physiological adaptation to alkali stress in oat in the view of ion balance absorption and distribution. After short-term stress, the cation contents in oat plants showed the variations of increased Na^＋, decreased K^＋, and minor changes in Ca^2＋ and Mg^2＋. Besides, the distribution proportions of the four ions in various organs were not significantly different between the two varieties. Compared to short-term stress, long-term stress resulted in larger in- crease ofNa^＋ content and larger decreases of K^＋, Ca^2＋, and Mg^2＋ contents in all organs of both varieties. Vao-9 absorbed more Na^＋ and Ca^2＋ than Baiyan 5, and the absorptions ofK^＋ and Mg^2＋ were not significantly different between varieties, but the distribution characteristics of the four ions in various organs were different between the two varieties. Under 100 mmol L-1 alkali stress, 5.9 percent Na^＋ in leaf were lower distributed and 13.5 percent K^＋, 28.9 Ca^2＋, 10.9 Mg^2＋ more distributed in Vao-9 than in Baiyan 5, 5.4 percent Na^＋ in stem higher and 9.8 K^＋ lower in Vao-9 than in Baiyan 5, 28.9 Ca^2＋, 10.9 Mg^2＋ in root were lower in Vao-9 than in Baiyan 5, As a result, the Na^＋ content and the ratios of Na^＋/K^＋, Na^＋/Ca^2＋, and Na^＋/Mg^2＋ in leaf were lower in Vao-9 than in Baiyan 5. Clearly, oat plant has the mechanism of selective absorption and distribution of various cations in different organs in response to alkali stress.
出处
《作物学报》
CAS
CSCD
北大核心
2014年第2期362-368,共7页
Acta Agronomica Sinica
基金
国家自然科学基金项目(31060174
30660084)
内蒙古自然科学基金项目(2010Zd07
200607010301)
国家现代农业产业技术体系建设专项(CARS-08-B-5)
内蒙古农业大学科技创新团队项目(NDTD2010-8)资助
关键词
碱胁迫
燕麦
阳离子平衡
Alkali stress
Oat
Cation iquilibrium
