【摘要】 采用沙培植物育苗法,以聚乙二醇6000(PEG-6000)模拟自然干旱,研究9份苏丹草(Sorghum sudanense)及3份高丹草(S. bicolor×S. sudanense)幼苗期对干旱胁迫的生理响应,并利用隶属函数法对其抗旱性进行综合比较。结果表明,抗旱性强的材料在干旱胁迫下保水能力强、叶绿素持有率高、能维持较高的光合性能和细胞膜结构的完整性。依据叶片相对含水量、相对电导率、丙二醛含量、叶绿素含量、光化学效率(Fv/Fm)、净光合速率和水分利用效率7项抗逆相关指标,对12份材料的抗旱隶属值进行计算,其综合抗旱适应性鉴定结果为,材料编号1、2和3的苏丹草与10(‘蜀草2号’高丹草)、11(‘蜀草1号’高丹草)及12(‘海狮’苏丹草)抗旱性较强,编号为7、8的两份苏丹草和9号高丹草抗旱性较差。本研究为高梁属作物抗旱新品种选育和优质牧草栽培利用提供了试验依据。更多还原

【Abstract】 The physiological responses of nine cultivars of Sorghum sudanense and three cultivars of S. bicolor × S.sudanense were studied under drought stress induced by polyethylene glycol 6000(PEG-6000) based on a sand culture experiment. The results show that materials with better drought tolerance have better water retaining capacity, higher chlorophyll content, and better photosynthesis and membrane integrity under drought stress. The drought tolerance of the 12 cultivars were evaluated by subordinate function values analysis according to seven physiological parameters(leaf relative water content, electrolyte leakage, malondialdebyde content, chlorophyll content, photochemical efficiency, net photosynthetic rate, and water use efficiency). Three S. sudanense cultivars(No. 1, 2, and 3) and cultivar No. 10(‘Shucao No. 2’ S. bicolor × S. sudanense), cultivar No. 11(‘Shucao No. 1’ S. bicolor × S. sudanense), and cultivar No. 12(‘HayKing ’ S. sudanense) had higher drought tolerance, and two S. sudanense cultivars(No. 7 and 8) and a S. bicolor × S.sudanense cultivar(No. 9) had lower drought tolerance. This study provides basal data for the cultivation and utilization of forages and selection of new cultivars with higher drought tolerance.更多还原