PEG胁迫下玉米苗期耐旱种质资源鉴定与评价

Identification and Evaluation of Drought Tolerant GermplasmResources at Seedling Stage of Maize under PEGStress

为建立玉米苗期耐旱能力评价体系,筛选优良的耐旱玉米种质资源,以东北地区常用的124份玉米自交系为供试材料进行苗期水培,利用20%PEG-6000模拟干旱,测定干旱胁迫下自交系株高、茎粗、根长、地上鲜重、地下鲜重、植株含水量、叶绿素相对含量等10个性状,计算各指标耐旱胁迫指数。利用综合隶属函数法,进行主成分分析、回归分析和聚类分析,综合评价各玉米材料耐旱能力。结果表明,叶绿素相对含量、地下鲜重、茎粗可作为玉米苗期耐旱能力筛选的首选指标,并根据苗期耐旱能力将自交系分为4类,分别为旱耐受、中抗性、旱敏感、极敏感;旱耐受自交系共9个,占材料总数的7.26%;中抗性自交系47个,占比37.90%;旱敏感自交系52个,占比41.94%;极敏感自交系16个,占比12.90%。

In order to establish an evaluation system of maize drought tolerance at seedling stage andscreenexcellent drought tolerant maize germplasm resources,124 maize inbred lines commonly used in Northeast China were used as test materials for hydroponics at seedling stage,and 20% PEG-6000 was used tosimulatedrought.The drought-stress tolerance index of inbred lines was calculated by measuring plant height,stemdiameter,root length,fresh weight aboveground,fresh weight underground,plant water content and chlorophyll relative content.Principal component analysis,regression analysis and cluster analysis were used toevaluatedrought tolerance of maize materials.The results showed that chlorophyll,fresh weight underground andstemdiameter could be used as the first choice indicators for screening drought tolerance of maize seedlings,andmaize seedlings could be divided into four categories,including drought tolerance,mediumresistance,drought sensitive and highly sensitive inbred lines.Drought tolerance inbred lines included nine inbred lines,accountingfor 7.26% of the total number of materials.There were 47 moderately resistant inbred lines,accounting for 37.90%;there were 52 drought sensitive inbred lines,accounting for 41.94%;there were 16 highly sensitiveinbred lines,accounting for 12.90% of the total material.