5个棉花品种的耐盐鉴定与筛选试验

为验证室内棉花苗期耐盐性鉴定结果的可靠性，在大田条件下对5个棉花品种在3个盐胁迫水平下的出苗率，3个生育期的叶绿素含量、光合速率、钠钾离子含量以及产量进行测定。结果显示，低盐浓度对棉花种子发芽影响较小，高盐浓度下的发芽势、发芽率才能较准确地反映棉花苗期的耐盐性，耐盐品种的筛选需要进行全生育期生理数据和终产量的综合评价才更可靠。本试验中仁和39号和中棉44号较其它3个品种在苗期有较好的耐盐性，泗棉3号耐盐性最差；重度盐碱相对轻度盐碱条件下产量下降比例，仁和39号、鲁棉研28号、中棉49号、泗棉3号和中棉44号分别为25．2％、26．7％、31．9％、32．2％和26．4％，说明仁和39号受盐胁迫影响最小，中棉44号和鲁棉研28号次之，中棉49号和泗棉3号耐盐性较差。

Identification and Screening Test on Salt Tolerance of Five Cotton Varieties

In order to verify the reliability of the identification results of cotton salt tolerance at seedling stage, the emergence rate, chlorophyll content, photosynthetic rate, sodium and potassium ion contents and yield of five cotton varieties were determined in field under three salt stress levels. The results showed that there was no significant effect on cotton seed germination at low salt concentration, but the germination potential and germination rate could reflect the salt tolerance of cotton seedlings under high salt concentration, so it was reliable to screen salt -tolerant varieties based on the comprehensive evaluation on physiological data of the whole growth period and final yield. The varieties of Renhe 39 and Zhongmian 44 had better salt tolerance at seedling stage compared to the other three varieties; Simian 3 had the worst salt tolerance. The yield of Renhe 39, SCRC 28, Zhongmian 49, Simian 3 and Zhongmian 44 decreased by 25.2%, 26.7% ,31.9%, 32.2% and 26.4% under severe salinity compared to light salinity, which indicated that Renhe 39 had the best salt tolerance, while Zhongmian 49 and Simian 3 had the worst; Zhongmian 44 and SCRC 28 was in the middle.