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期 刊 ：植物遗传资源学报 2015年 16卷 5期

关键词：甘薯；抗旱鉴定；渗透胁迫；生理指标；

Keywords:Sweetpotato, Drought-resistance identification, Osmotic stress, Physiological index,

摘 要 ：为加速甘薯抗旱新材料筛选以及抗旱新品种选育，促进甘薯在丘陵旱薄地、内陆干旱地等边际土地的种植利用，减少田间鉴定工作量，需要建立一种室内辅助鉴定甘薯耐旱性的方法，对鉴定材料进行初选。本研究在田间鉴定甘薯抗旱性的基础上，室内PEG-6000模拟水分胁迫，研究不同胁迫下生理指标变化及其与抗旱性的关系。研究结果表明：经田间抗旱鉴定，广薯87和徐薯22的抗旱性强，日紫0602和宁紫薯1号的抗旱性差；在PEG6000模拟水分胁迫下，甘薯叶片NOS、CAT、T-AOC和T-SOD活性随着PEG浓度增高，其活性增强；Pro、MDA、Prot和T-AA含量也增加；尤其在25%PEG-6000胁迫处理24 h，甘薯叶片NOS、T-AOC、Pro的相对值与抗旱指数呈显著正相关，RWC相对值与抗旱指数呈极显著正相关，这四个指标的加权录属函数值D与抗旱指数呈显著正相关（r=0.8944）；因此，可用这四个指标的D值对甘薯抗旱性进行初步鉴定。

Abstract:A kind of auxiliary identification method of sweetpotato drought-resistance need be established to drought screening of new materials and breeding drought-resistance new varieties，promote sweetpotato planting in dry barren hills，inland arid etc. marginal land，reduce the workload of field identification. On the basis of identification of sweetpotato drought-resistance in the field, PEG-6000 simulate water stress, the relation of drought-resistance and physiological changes under was discussed. The results show that: Through drought identification in the field, Guangshu87 and Xushu22 have strong drought-resistance, Rizi0602 and Ningzishu1 have poor drought-resistance. Under stress, with the increasing of PEG concentration , the activity of NOS, CAT, T-AOC and T-SOD of sweetpotato leaves increased gradually, the content of Pro, MDA, Prot and T-AA also increased; especially after 24 h sweetpotato leaves were treated in 25% PEG-6000, drought resistance index and the relative values of NOS,T-AOC,Pro of sweetpotato leaves showed a significant positive correlation，the relative value of RWC and drought resistance index showed a highly significant positive correlation，drought resistance index and D value of NOS,T-AOC, Pro, RWC showed a significant positive correlation（r=0.8944）.so the D value of this four physiological indexes could be used for preliminary identification of sweetpotato drought-resistance.

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