摘要
为了研究苜蓿(Medicago sativa)节水品种筛选碳同位素分辨率替代指标的可行性,在宁夏中部干旱带采用喷灌方法,设置3种水分处理,即,严重水分胁迫处理(全生育期不灌水)、中等水分胁迫(灌溉302mm)和充分灌水(562mm),对10个品种苜蓿材料始花期和盛花期的整株和叶片碳同位素分辨率(Δ13 C)与灰分含量、比叶重及叶片相对含水量、光合气体交换参数等之间的关系进行了研究。结果发现,水分处理对叶片及整株Δ13 C、叶片灰分含量、叶片相对含水量及叶片光合气体交换参数有显著影响(P<0.05)。严重水分胁迫条件下整株Δ13 C与比叶重呈负相关;严重水分胁迫及中度水分胁迫条件下叶片相对含水量与叶片Δ13 C及整株Δ13 C呈显著正相关;在严重水分胁迫条件及中度水分胁迫条件下整株灰分含量均与整株Δ13 C呈显著负相关;在中度水分胁迫处理下,叶片Δ13 C与气孔导度呈显著正相关。在宁夏半干旱地区有限供水的条件下,苜蓿的叶片比叶重、相对含水量和整株灰分含量可以作为叶片Δ13 C的替代指标来预测苜蓿的蒸腾效率。
In order to study the substitution indexes of carbon isotope discrimination for alfalfa, ten varieties of alfalfa materials were planted under three water conditions, including severe drought stress （with 0 mm irrigation）, moderate drought stress （with 302 mm irrigation） and well watered （with 562 mm irrigation）, in arid area of central Ningxia. Relationships betweer AlaC（carbon isotope discrimination） and ash con- tent, specific leaf dry weight, leaf relative water content, photosynthetic gas exchange parameters in leaf and whole plant were studied at the beginning of flowering stage and flowering stage. The results showed that there was significant effect of water treatment on leaf and whole plant AlaC, leaf ash content, specific leaf dry weight and photosynthetic gas exchange parameters. Specific leaf dry weight and whole plant A13C were negatively correlated under severe drought stress. Leaf relative water content was positively related with whole plant A13C under severe drought stress and moderate drought stress. Negative correlation between ash content and whole plant AlaC was observed under severe drought stress and moderate drought stress. It was accordingly concluded that specific leaf dry weight, leaf relative water content and whole plant ash content might be considered as the substitution indexes of carbon isotope discrimination to predict transpiration efficiency of alfalfa under water limited condition in arid area of Ningxia.
出处
《草业科学》
CAS
CSCD
北大核心
2013年第12期2011-2017,共7页
Pratacultural Science
基金
教育部科学技术研究重点项目(211195)
国家自然科学基金项目(31160478)
关键词
碳同位素分辨率
蒸腾效率
替代指标
苜蓿
carbon isotope discrimination
transpiration efficiency
substitution indexes
alfalfa
