中文摘要：

为了解西南麦区小麦品种苗期抗旱性和筛选适宜鉴定指标,利用盆栽和大田干旱棚2种栽培方式,对西南地区42个小麦品种进行自然干旱胁迫。盆栽试验测定苗期叶面积（X_1）、苗高（X_2）、根长（X_3）、地上部干重（X_4）、地下部干重（X_5）、全株干重（X_6）、根冠比（X_7）、植株含水率（X_8）、离体叶片失水速率（X_9）、叶绿素含量（X_（10））等10个指标,大田控水试验于收获期测定株高（X_（11））、小穗数（X_（12））、穗长（X_（13））、单株成穗数（X_（14））、单穗重（X_（15））、单株产量（X_（16））等6个指标。以各指标的抗旱系数作为衡量抗旱性的依据,运用加权隶属函数、聚类分析、逐步回归等方法对小麦抗旱性进行综合评价及分类。结果表明,42个小麦品种可划分为水分敏感、弱抗旱、中度抗旱和强抗旱4种抗旱类型,分别包括3、23、13和3个品种。以苗期和收获期16个指标的抗旱系数为基础,利用逐步回归方法建立了小麦苗期抗旱性评价回归模型：D1=-1.593＋0.152 X_1＋0.293 X_2＋0.256 X_3＋0.151 X_5＋0.426 X_6＋0.107 X_7＋0.958 X_12＋0.085 X_14＋0.056 X_（15）＋0.205 X_（16）,R2=0.998 8,平均拟合精度99.23%;利用苗期10个指标的抗旱系数进行逐步回归分析建立小麦苗期抗旱性评价回归模型：D2=-0.677＋0.218 X_1＋0.481 X_3-0.803 X_4＋0.230 X_5＋1.232 X_6,R2=0.674 0,平均拟合精度88.50%,表明用苗期性状结合产量性状评判小麦抗旱性更为可靠准确。

英文摘要：

The objectives of this study were to evaluate the drought resistance and screen indexes for 42 wheat cultivars seedlings in the southwest of China.Natural drought stress was performed by pot culture and field cultivation.Then 10 traits leaf area（X_1）,seedling height（X_2）,root length（X_3）,shoot dry weight（X_4）,root dry weight（X_5）,the whole plant dry matter accumulation（X_6）,root shoot ratio（X_7）,plant water content（X_8）,containing excised-leaf water loss rate（X_9）,chlorophyll content（X_（10））of wheat cultivars cultured in pot and 6indicators obtaining plant height（X_（11））,spikelet number（X_（12））,spike length（X_（13））,panicle number per plant（X_（14））,single spike weight（X_（15））,yield per plant（X_16）of wheat cultivars cultivated in field in harvest time were measured.Comprehensive assessment on drought resistance and classification of these wheat cultivars were implemented by using weighted membership function,clustering analysis and stepwise regression based on every indexof drought resistance coefficient.The results suggested that：42wheat cultivars were divided into four drought-tolerant types by cluster analysis,3of the 42 varieties were drought-sensitive type,23 varieties were weak drought-resistance type,13 were medium drought-resistance type,and 3 were high drought-resistance type.A mathematical evaluation model for wheat drought tolerance was established that containing 16 drought resistance coefficients of seeding stage and harvest period by means of regression analysis,and D1=-1.593＋0.152 X_1＋0.293 X_2＋0.256 X_3＋0.151 X_5＋0.426 X_6＋0.107 X_7＋0.958 X_（12）＋0.085 X_（14）＋0.056 X_（15）＋0.205 X_（16）,R2=0.998 8.Average fittingaccuracy of all varieties were 99.23%.A mathematical evaluation model for wheat drought tolerance was established that containing 10 drought resistance coefficients of seeding stage by means of regression analysis,and D2=-0.677＋0.218 X_1＋0.481 X_3-0.803 X_4＋0.230 X