凉山州马铃薯主栽品种苗期抗寒性分析

Analysis on Cold Resistance of Main Potato Varieties at Seedling Stage in Liangshan Prefecture

为研究马铃薯苗期离体叶片对短期低温胁迫的生理响应,选用陇薯3号、陇薯7号、丽薯6号、代S、荷兰15、凯薯2号为试验材料,取苗期叶片放置于4℃冰箱中,于处理后0、6、12、24 h分别测定相关的生理指标(可溶性糖含量、MDA含量、POD活性、叶绿素含量)。结果表明,经过低温胁迫后,可溶性糖含量、叶绿素含量整体在短时间内均呈现下降的态势,而后快速上升;POD活性和MDA含量在6 h内出现缓慢上升态势,后快速上升,在12 h时达到最高值,而后又急剧下降。POD活性与叶绿素含量、MDA含量成极显著正相关,与可溶性糖含量成显著正相关;叶绿素含量与MDA含量成显著正相关。采用隶属函数法对这些品种的苗期抗寒性进行综合评价,品种抗寒性的排列顺序为荷兰15>陇薯3号>凯薯2号>代S>陇薯7号>丽薯6号。

In order to study the physiological response of in vitro potato leaves to short-term low temperature stress at the seedling stage,Longshu 3,Longshu 7,Lishu 6,Dai S,Holland 15 and Kaishu 2 were selected as the experimental materials.The leaves at the seedling stage were placed in a refrigerator(4℃),and the relevant physiological indicators(soluble sugar content,MDA content,POD activity,chlorophyll content)were determined at 0 h,6 h,12 h and 24 h respectively after treatment.The results showed that after low temperature stress,the soluble sugar content and chlorophyll content as a whole decreased in a short time,and then increased rapidly;POD activity and MDA content slowly increased within 6 h,then increased rapidly and reached the highest value at 12 h,then fell sharply.POD activity had an extremely significantly positive correlations with chlorophyll content and MDA content;POD activity was significantly positively correlated with soluble sugar content;chlorophyll content was significantly positively correlated with MDA content(P<0.05).The affiliation function method was used to comprehensively evaluate the cold resistance of these varieties at seedling stage.The order of cold resistant varieties was Holland 15>Longshu 3>Kaishu 2>Dai S>Longshu 7>Lishu 6.