马铃薯幼苗对根际低氧胁迫的生长响应及耐性分析

摘要

为明确马铃薯抗湿性,筛选耐湿品种,本文采用盆栽淹水处理的方法,以国内外14个马铃薯品种资源为试验材料,研究了低氧胁迫对植株生长的影响,并利用湿害指数(WI)、抗逆系数(ARC)以及聚类分析方法分析了不同马铃薯品种资源幼苗耐低氧性的差异,对14个供试品种资源进行了耐低氧性综合评价.结果表明,与正常栽培(对照)比较,淹水处理显著降低了“乌洋芋”、“早大白”、“Favorita”和“Vagor”品种的植株鲜重、植株干重、新叶数、株高和根系长度,其平均抗逆系数为0.61～0.68,这4个品种对根际低氧胁迫敏感；而“竹根”、“藏薯1号”和“克新12号”品种在低氧逆境下,植株生长受到的抑制相对较小,其平均抗逆系数在0.90～0.93,说明其对低氧胁迫的抗性较强；其余7个品种(“克新16号”、“克新1 8号”、“713NS51-5”、“717NS78-7”、“Cersa”、“458 DTO-33”和“川芋”)的平均抗逆系数在0.75～0.83,对低氧胁迫有一定的抗性.此外,在淹水处理第8d时,“Vagor"和“Favorita”的湿害指数均达到3.0,死亡率分别为47%和50%,耐湿性最差；“克新18号”、“乌洋芋”和“早大白”的湿害指数为2.5～2.8,耐湿性较差；“竹根”、“克新12号”、“藏薯1号”和“克新16号”的湿害指数为0.2--0.8,耐湿性最强；其余品种(“713NS51-5”、“717NS78-7”、“Cersa”、“458 DTO-33”和“川芋”)居中,湿害指数为1.4～1.9.综合抗逆系数(ARC)、湿害指数(WI),结合聚类分析的评价结果,将供试的14个马铃薯品种分为4大类:耐低氧品种(“竹根”、“藏薯1号”和“克新12号”),中等耐低氧品种(“克新16号”、“713NS51-5”、“717NS78-7”、“458DTO-33”、“川芋”和“Cersa”),不耐低氧品种(“克新18号”、“乌洋芋”和“早大白”),低氧敏感品种(“Favorita”和“Vagor").%In order to analyze the waterlogging resistance of different potato varieties and screen waterlogging resistant genotypes, this paper investigated the effects of root-zone hypoxia stress on seedling growth of 14 potato varieties under pot-cultured waterlogging condition. The waterlogging-tolerance of these potato varieties was comprehensively evaluated according to the adversity resistance coefficient (ARC), waterlogging index (WI) and cluster analysis. The results showed that compared with normal cultivation (control), waterlogging significantly decreased plant fresh weight, dry weight, new leaf number, height and maximum length of new root of "Wuyangyu", "Zaodabai", "Favorita" and "Vagor" with the average ARC of 0.61 ~0.68, which indicated that those four varieties were sensitive to root-zone hypoxia stress. The plant growth was not significantly inhibited for "Zhugen", "Zangshu-1" and "Kexin-12" under hypoxic conditions with the average ARC of 0.90-0.93, those three species showed higher waterlogging tolerance. "Kexin-16", "Kexin-I8", "713NS51-5", "7I7NS78-7", "Cersa", "458 DTO-33" and "Chuanyu" had a certain degree of tolerance to hypoxia stress with the average ARC of 0.75-0.83. After 8 days for waterlogging treatment, "Vagor" and "Favorita" showed the lowest waterlogging tolerability, with the highest Wl of 3.0 and mortality rate of 47% and 50%. "Kexin-18", "Wuyangyu" and"Zaodabai" were poorly waterlogging resistant with the W] of 2.5-2.8; while "Zhugen", "Zangshu-1", "Kcxin-12" and "Kcxin-16" had higher waterlogging tolerance with the Wl of 0.2-0.8. "713NS51-5", "717NS78-7", "Cersa", "458 DTO-33" and "Chuanyu" were intermediately waterlogging tolerant with the WI of 1.4-1.9. The comprehensive evaluation on hypoxia stress tolerance with ARC, WI and cluster analysis divided 14 potato varieties into four groups, the high tolerant varieties of "Zhugen", "Zangshu-1" and "Kcxin-12"; medium tolerant varieties of "Kexin-16", "713NS51-5", "7I7NS78-7", "458DTO-33", "Chuanyu" and "Cersa"; no-tolerant varieties of "Kexin-18", "Wuyangyu" and "Zaodabai"; sensitive varieties of "Favorita" and "Vagor".