打破野生藏沙蒿种子休眠方法的筛选与评价

为筛选能够打破野生藏沙蒿（Artemisia wellbyi）种子休眠的适宜方法,本研究采用不同温度的温水浸种,不同浓度硝酸钾（KNO₃）、赤霉素（GA₃）、吲哚乙酸（IAA）、微量元素浸种以及不同浓度过氧化氢（H₂O₂）、聚乙二醇（PEG-6000）浸泡滤纸等7种方法处理藏沙蒿种子,测定种子萌发及活力指标,并利用隶属函数法将各指标进行综合评价。结果表明：随着KNO₃浓度的升高,藏沙蒿种子的相对发芽率呈现升高的趋势;且高浓度KNO₃对藏沙蒿种子根的伸长有较高促进作用;低浓度的GA₃,IAA,PEG-6000和30℃温水浸种对藏沙蒿种子萌发有促进效果;微量元素浸种对藏沙蒿种子的萌发影响较对照差异不显著;较高H₂O₂浓度下藏沙蒿发芽指数有所升高,但对其根长和芽长有一定抑制作用。综合分析,不同浓度GA₃,10 mg·L^-1IAA浸种处理12 h对藏沙蒿种子的萌发促进效果整体最优,可以作为打破藏沙蒿种子休眠的适宜方法。

Screening and Evaluation of Methods for Breaking Seed Dormancy of Wild Artemisia wellbyi

In order to screen the suitable methods to break the seed dormancy of Artemisia wellbyi,seven methods were conducted as using different temperatures of warm water,different concentrations of potassium nitrate,gibberellin (GA₃),indole-3-acetic acid (IAA),or trace elements to soak seeds,and using the hydrogen peroxide,polyethylene glycol-6000 (PEG-6000) solution to immerse filter paper in this study. The germination and vitality indexes of the seeds were determined,and the indexes were evaluated by the membership function method comprehensively. The results showed that,with the increase of potassium nitrate concentration,the relative germination rate of A. wellbyi seeds showed an increasing trend,and the higher concentration of potassium nitrate played an important role to promote the elongation of seed roots of A. wellbyi. The methods of soaking seeds with lower concentrations of GA₃,IAA,PEG-6000 and 30℃ warm water could promote the seed germination. The effect of different concentrations of trace elements on seed germination of A. wellbyi was not significantly different from the control. At the higher H₂O₂ concentration,the germination index of A. wellbyi increased,but the root and bud length were inhibited to some extent. Comprehensive analysis showed that the germination promoting effect of soaking seeds with each concentration of GA₃ and 10 mg·L^-1 IAA for 12 hours was the highest,which can be used as suitable methods to break the dormancy of A. wellbyi seeds.