复盐胁迫对木薯苗期生长和根系生长发育的影响

Effects of Mixed Saline Stress on Growth and Root Development of Cassava Seedlings

以木薯新选048、GR911、SC8为材料,用2种中性盐NaCl和Na_2SO_4配制成不同浓度的溶液,对木薯进行30d复盐胁迫处理,测定木薯的株高、地上生物量、地下生物量、根长、根表面积和根体积,探讨了NaCl-Na_2SO_4胁迫对木薯苗期生长和根系生长发育的影响。结果表明:生物量和根冠比变化因品种和盐浓度而异,总体表现为低浓度NaCl-Na_2SO_4胁迫(0.05 mol/L)抑制作用不大,甚至有促进作用,但随着NaCl-Na_2SO_4胁迫浓度的增加,抑制作用越来越明显。低浓度NaCl-Na_2SO_4盐胁迫对木薯幼苗根系生长影响不明显,但高浓度盐胁迫明显抑制木薯幼苗根系的生长。NaClNa_2SO_4胁迫对新选048幼苗生长的抑制作用最大,GR911次之,SC8最小。因此,SC8对盐胁迫的适应性强于新选048、GR911、SC8的耐盐性较强。

In order to explore the effects of mixed saline stress on the growth and root development of cassava seedlings,the author used different concentrations of NaCl-Na2SO4 mixed solutions to treat the seedlings of cassava varieties Xinxuan 048,GR911 and SC8 for 30 days,and determined the plant height,aboveground biomass,underground biomass,root length,root surface area and root volume of stressed cassava seedlings.The results showed that：in general,the biomass and root-shoot ratio of cassava seedlings were inhibited（even promoted） slightly under low-concentration（0.05 mol/L） NaCl-Na2SO4 stress;however,along with the increase in NaCl-Na2SO4 concentration,the inhibitory effect was more and more obvious.The effect of low-concentration NaCl-Na2SO4 stress on the root growth of cassava seedlings was not obvious,but high-concentration NaCl-Na2SO4 stress markedly inhibited the root growth of cassava seedlings.NaCl-Na2SO4 stress had the greatest,moderate and the weakest inhibitory effects on the seedling growth of Xinxuan 048,GR911 and SC8,respectively,indicating that SC8 had a stronger adaptability and tolerance to mixed saline stress than Xinxuan 048 and GR911.