In this research,we selected Zhongzhu-1,Tri-1 and Xiangzhu-7 to study the growth and physiological characteristics of these 3 ramie varieties under soil drought stress with four different soil content levels:normal water supply(75％ ～ 80％ of capacity,CK),continuous droughts of 6 d,continuous droughts of 12 d,continuous droughts of 24 d.The result showed that drought stress can affect the growth of ramie,resulting in lower growth rate.The degree of wilting of ramie was positively correlated with drought stress duration.With the increasing of continuous drought stress,the degree of growth rate,leaf SPAD value,root activity of three ramie varieties affected was:Tri No.1 ＞ Zhongzhu No.1 ＞ Xiangzhu No.1.Under PD12 treatment,the POD value of Tri-1 reached the peak,and that of Zhongzhu No.1 and Xiangzhu No.7 was positively correlated with drought stress duration.The impact on ramie was increased with the duration of the stress,and there were differences among different ramie varieties.Comprehensive analysis displayed that under the persistent drought conditions,the drought resistances for the 3 ramie varieties were Xiangzhu No.7 ＞ Zhongzhu No.1 ＞ Tri No.1.%以中苎1号、多倍体1号和湘苎7号为试验材料,采用盆栽模拟干旱胁迫法,设置常规灌溉(土壤含水量为田间最大持水量的75％ ～ 80％,CK)、持续干旱6 d(Persistent droughts 6 d,PD6)、持续干旱12 d(Persistent droughts 12 d,PD12)和持续干旱24 d(Persistent droughts 24 d,PD24)4个处理,探索干旱持续天数对苎麻生长及生理生化的影响.结果表明:干旱胁迫影响苎麻长势,导致生长速率降低.苎麻萎蔫程度与干旱胁迫持续天数呈正相关.随着干旱胁迫时间的延长,从生长速度、叶片SPAD(叶绿素含量)值、根系活力的下降程度来看,3个品种受到的影响大小为:多倍体1号＞中苎1号＞湘苎7号;从影响根系过氧化物酶(POD)活性来看,在PD12处理下,多倍体1号POD值达到了峰值,而中苎1号和湘苎7号与干旱程度呈现出正比例关系.胁迫持续天数越久对苎麻的影响越大,且不同苎麻品种间存在差异.综合分析得出:在持续干旱条件下,3个苎麻品种的抗旱性强弱顺序为湘苎7号＞中苎1号＞多倍体1号.
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