摘要
研究选用耐旱性强的 定西24 和 高原671 与耐旱性弱的 高原448 和 青春533 春小麦品种,在盆栽条件下比较了不同耐旱性品种在拔节后经不同程度水分胁迫后叶片的多种生理参数:叶片相对含水量、净光合速率、叶绿素a、叶绿素b、叶绿素总量和类胡萝卜素含量.结果表明:在土壤相对含水量75%、55%、40%和30%这4个等级上,这些生理指标均随土壤相对含水量的降低而下降,耐旱性强的品种降低慢,且降低幅度小.在水分胁迫下,4个品种叶片的叶绿素a、叶绿素b和叶绿素总量下降,证明此时光合器官的生理功能遭到破坏;在轻度水分胁迫下,耐旱性强的品种定西24和高原671叶片的类胡萝卜素含量上升;在严重水分胁迫下,4个品种的叶片类胡萝卜素含量明显下降,可能此时自由基积累超过了抗氧化剂的清除能力,从而使细胞受到损伤.根据本研究结果,可以将轻度水分胁迫下叶片类胡萝卜素含量升高作为春小麦品种耐旱性的选择指标之一.
Four spring wheat cultivars which had different droughttolerance were planted in flower pots with an inside diameter of 28 cm and a height of 30 cm. Just after the cultivars reached elongation stage, soil relative water contents in the pots were controlled to 75%, 55%, 40% and 30% levels. The effects of water stress on relative water content, net photosynthetic rate and pigment contents in the second leaves of the cultivars were studied. The relative water content in leaves and net photosynthetic rate decreased as compared with those in control with the decline of soil relative water content, but droughtresistant cultivars Dingxi 24 and Plateau 671 decreased to a less extent. Under water stress, Chlorophyll a, Chlorophyll b, and total chlorophyll content also decreased. But compared with droughtsensitive cultivars Plateau 448 and Qingchun 533, droughtresistant cultivars Dingxi 24 and Plateau 671 decreased to a less extent. Carotinoid contents in leaves of droughtresistant cultivars Dingxi 24 and Plateau 671 under less water stress increased. However, carotinoid contents in leaves of the four cultivars decreased significantly under severe water stress. The increase of carotinoid content in leaves under less water stress could be used as a selected marker for droughttolerance.
出处
《西北植物学报》
CAS
CSCD
2003年第5期811-814,共4页
Acta Botanica Boreali-Occidentalia Sinica
基金
中国科学院知识创新工程方向项目的 优质耐旱小麦选育与推广KSCX2-1-01-1-03 资助
