干旱胁迫对冬马铃薯苗期生理指标及光合特性的影响

Effects of Drought Stress on Physiological Index and Photosynthetic Traits at Seedling Stage of Winter Potato

【目的】采用盆栽冬种的方式,研究干旱胁迫对4个马铃薯品种(会-2、合作88、丽薯6号和宣薯2号)苗期生理指标及光合参数的影响,为冬马铃薯抗旱栽培及为选择优质耐旱冬马铃薯品种奠定了理论基础。【方法】选用云南主栽的4个马铃薯品种(会-2、合作88、丽薯6号和宣薯2号),对其进行干旱胁迫。当土壤含水量为田间最大持水量的20%~40%时,对脯氨酸含量、可溶性糖含量、可溶性蛋白含量、超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)、丙二醛(MDA)、土壤含水量、叶绿素a、叶绿素b、叶绿素a/b、总叶绿素、蒸腾速率、净光合速率、气孔导度、胞间CO_2浓度进行测定分析。【结果】干旱胁迫下,脯氨酸含量、可溶性糖含量、可溶性蛋白含量、超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)、丙二醛(MDA)均比对照增加;干旱胁迫下,土壤含水量、叶绿素a、叶绿素b、叶绿素a/b、总叶绿素、蒸腾速率、净光合速率、气孔导度、胞间CO_2浓度均比对照降低;叶绿素a比叶绿素b对干旱胁迫更敏感;4个品种干旱胁迫结果存在显著差异,抗旱性由强到弱依次是:会-2>宣薯2号>合作88>丽薯6号。【结论】在重度水分胁迫下,马铃薯的生理特性、光合参数的变化与品种的抗旱性密切相关。

[ Purpose]Four potato varieties （Hui-2, Hezuo88, Lishu6 and Xuanshu2） were cultivat- ed in pots in winter, and the effects on physiological indexes and photosynthetic parameters were stud- ied under drought stress to provide a theoretical base for drought resistant cultivation and quality drought-tolerant winter potato varieties selection. [ Methodl Four main potato cultivars （Hui-2, He- zuo88, Lishu6 and Xuanshu2） used in Yunnan, were selected for drought stress. When the soil mois- ture content was 20% to 40% of the maximum amount of water in the field, the proline content, solu- ble sugar content, soluble protein content, SOD activity, POD activity, CAT activity, MDA content, soil water content, chlorophyll a, chlorophyll b, chlorophyll a/b, total chlorophyll, transpiration rate, net photosynthetic rate, stomatal conductance and intercellular CO2 concentration were detected. [ Re- sults] The proline content, soluble sugar content, soluble protein content, SOD activity, POD activi- ty, CAT activity and MDA content increased significantly under drought stress, however, the soil watercontent, chlorophyll a, chlorophyll b, chlorophyll a/b, total chlorophyll, transpiration rate, net photo- synthetic rate, stomata/ conductance, intercellular CO2 concentration decreased. Chlorophyll a was more sensitive than chlorophyll b. Drought resistance ranks of four potato cultivars were as follows： Hui-2 〉 Xuanshu 2 〉 Hezuo88 〉 Lishu 6. [ Conclusion] Under severe drought stress, the changes ofphysiological properties, fluorescence parameters are closely related with drought resistance.