水分胁迫对不同基因型苦荞苗期根系生理特性及产量的影响

Effects of water on root physiological characteristics at seedling stage and yield of different tartary buckwheat

采用盆栽人工控水试验,研究了不同水分处理(正常供水、中度干旱和重度干旱)对不同抗旱基因型苦荞(迪庆苦荞、云荞1号、多元苦荞)生理、形态指标以及产量构成的影响。结果表明:(1)随水分胁迫加剧,参试品种苗期株高、茎粗、叶面积、地上部干重、总根体积、总根面积、叶绿素含量、叶片相对含水量、PSII潜在活性Fv/Fo、最大光化学效率Fv/Fm、根系活力及可溶性蛋白含量均明显降低,且表现为多元苦荞>云荞1号>迪庆苦荞。(2)苗期根冠比、根系SOD、POD活性、根系MDA、游离脯氨酸和可溶性糖含量随干旱胁迫加深均增大,增幅表现为:迪庆苦荞>云荞1号>多元苦荞。中度胁迫刺激了各基因型苦荞主根长生长,但在重度胁迫下三个品种均受到抑制,迪庆苦荞受影响最小。(3)成熟期各品种主茎分枝数、单株粒数、百粒重等指标也表现为随干旱胁迫加剧呈下降的趋势,其中单株粒数降幅最为明显。分析表明:在干旱逆境下,不论是形态指标和生理指标,还是产量构成,均为迪庆苦荞表现最佳,优势突出,表明其在干旱逆境下具有更强的适应能力;多元苦荞抗旱性最差,云荞1号属中间型。

The effects of three different water stresses on the physiomorphological characteristics and root associated physiological characteristics of the tartary buckwheat（ ‘Di Qing＇,‘Yunqiao1 ＇,and ‘Duoyuan＇） during the seedling stage were studied in a pot experiment. The results showed that：（ 1） With aggravation of water stress,Testing varietiess＇ seedling plant height,stem diameter,leaf area,shoot dry weight,total root volume,total root area,chlorophyll content,leaf relative water content and potential activity of PSII Fv/Fo and the maximal photochemical efficiency of Fv/Fm,root activity and soluble protein content declined,but the drop is different,is shown as： Duoyuan 〉Yunqiao1 〉Di Qing.（ 2） Root/shoot ratio,root SOD,POD activity,root MDA,Content of proline and soluble sugar with deepening of drought stress is on the rise,is shown as： Di Qing 〉Yunqiao1 〉Duoyuan.Maximum root length under moderate stress has a trend of elongation,but three varieties were depressed at the influence of severe stress,and the depression of Di Qing is most smallest.（ 3） With aggravation of water stress,branches of main stem、grains per plant、100-seed mass of tested varieties declined at mature stage,Grains per plant was most obvious. Analysis showed that,under the drought stress,whether the obvious morphological indices,root SOD,POD that scavenging free radical and yield at mature stage etc.,Pingqiao2 all have a good performance,prominent superiority. In short,Di Qing under drought stress has a stronger ability to adapt,worst drought resistance of Duoyuan,Yunqiao1 belong to the intermediate type.