苏丹草生长早期耐旱性评价方法及种质耐旱性筛选

本研究采用Hoagland营养液砂培法,以PEG-8000为水分胁迫物,建立了苏丹草(Sorghum sudanense)生长早期耐旱性评价方法,并评价了22份苏丹草种质材料的耐旱性。结果表明:不耐旱基因型'06-222'能忍受的PEG-8000的最高浓度为-0.675 MPa。当PEG-8000的浓度为-0.600和-0.700 MPa时,22份苏丹草种质材料在相对存活率、相对株高及相对地上部干质量3个性状上的差异均达极显著水平。按照耐旱指数,将22份苏丹草种质材料分为5类,其中,'内农1号'、'89-105'及'TS185'的耐旱性最强,而'06-222'最弱。相对存活率和相对地上部干质量均与相对株高间存在较强的相关性。因此,对苏丹草进行生长早期耐旱性评价时PEG-8000的最高浓度应在-0.675 MPa左右;在评价苏丹草早期的耐旱性时考察相对存活率和相对地上部干质量2个性状即可。

Evaluation Method and Screening of Drought Tolerance of Elite Germplasm in the Early Growth Stage of Sudangrass

A sand culture experiment with Hoagland solution plus PEG-8000 was conducted to evaluate the drought tolerance of 22 sudangrass genotypes in the early growth stages. The results showed that a weak drought-tolerant genotype, '06-222', could tolerate up to PEG-8000 of-0.675 MPa. Under the PEG-8000 of-0.600 and-0.700 MPa, the relative livability(RL),relative dried mass(RDM) and relative plant height(RH) of sudangrass were significant different among the 22 genotypes. According to drought tolerance index(DTI), 22 studied genotypes were generally classified into five groups. 'Neinong-1', '89-105' and 'TS185' genotypes were the most drought tolerance compared to others. Correlation analysis suggested both RL and RDM possessed a strong correlation with RH. In conclusion, in evaluating the drought tolerance of sudangrass genotype, the maximum concentration of PEG-8000 was about-0.675 MPa and two traits, RL and RDM, could be used to investigate the drought tolerance of genotypes.