Effects of Uniconazole on Physiological and Biochemical Properties of Roots of Different Sweetpotato Cultivars at Seedling Stage

烯效唑对不同耐旱性甘薯苗期根系生理生化特性的影响（英文）

Objective] This study almed to investigate the effects of uniconazoIe on physioIogical and biochemical properties of roots of different sweetpotato cuItivars at seedIing stage. [Method] Under hydroponic conditions in a greenhouse, the effects of exogenous uniconazoIe on physioIogical and biochemical properties of roots of different sweetpotato cuItivars at seedIing stage were analyzed under continuous drought stress simuIated by PEG-6000. [Result] Compared with normal water suppIy treatment （N）, drought treatment （D） decreased significantIy root Iength, root surface area, average root diameter and root voIume of Jishu 21 and Jihei 1; to be specif-ic, compared with Jishu 21, root Iength, root surface area and average root diame-ter of Jihei 1 decreased greatIy, but root voIume of Jihei 1 decreased sIightIy. SOD, POD, APX activities and MDA content of Jishu 21 and Jihei 1 increased, and root vitality of two sweetpotato cuItivars was reduced; to be specific, compared with Jihei 1, Jishu 21 exhibited significantIy improved SOD, POD, APX activities, sIightIy im-proved MDA content and remarkabIy reduced root vitality. IAA, GAs and ZR con-tents of Jishu 21 and Jihei 1 decIined at seedIing stage; ABA content of two sweetpotato cuItivars was improved; to be specific, compared with Jihei 1, IAA, GAs and ZR contents of Jishu 21 were reduced sIightIy, whiIe ABA content of Jishu 21 was improved sIightIy. Under stress conditions, uniconazoIe treatment increased sig-nificantIy root Iength and root surface area of Jihei 1 and increased sIightIy root voIume of Jihei 1 compared with Jishu 21; uniconazoIe treatment increased signifi-cantIy SOD, POD and APX activities and root vitality of Jihei 1 and decIined re-markabIy MDA content of Jihei 1 compared with Jishu 21; uniconazoIe treatment in-creased significantIy IAA, ZR and ABA contents of Jihei 1 compared with Jishu 21. [Conclusion] Drought-toIerant sweetpotato cuItivar Jishu 21 exhibits high pIasma membrane integrity and root vitality by increasing activities of antioxidant enzymes under drought stress and malntalning high contents of IAA, ZR and ABA. Unicona-zoIe exerts greater reguIatory effects on physioIogical and biochemical properties of drought-sensitive sweetpotato cuItivar Jihei 1 under drought stress.

[目的]探究烯效唑对不同耐旱性甘薯苗期根系生理生化特性的影响。[方法]通过温室水培方式,采用PEG-6000模拟连续干旱法,研究了外源烯效唑对不同耐旱性甘薯苗期根系的生理生化特性影响。[结果]与正常供水处理相比,干旱显著降低了济薯21和济黑1的根长、根表面积、根平均直径和根体积,但济黑1的根长、根表面积和根平均直径降幅较大,根体积的降幅较小;2个品种的SOD、POD、APX活性和MDA含量均增高,根系活力均降低,但济薯21的SOD、POD和APX活性增幅较大,MDA增幅较小,根系活力降幅较小;2个品种苗期根系的IAA、GAs和ZR含量显著降低,ABA含量显著增加,但济薯21苗期根系的IAA、GAs和ZR含量降幅较小,ABA含量增幅也较小。在干旱处理中,烯效唑对济黑1的根长、根表面积增幅较大,对其根体积的增幅较小;烯效唑对济黑1的SOD、POD、APX活性和根系活力增幅较大,MDA含量降幅也较大;烯效唑对济黑1苗期根系的IAA、ZR和ABA含量增幅均高于济薯21。[结论]耐旱性强的济薯21主要通过提高干旱胁迫下的抗氧化酶活性和维持较高的IAA、ZR和ABA含量,以提高细胞质膜完整性和植株根系活力;烯效唑对干旱条件下干旱敏感型济黑1的调控效果更明显。