盐处理对甜菜生长和渗透调节物质积累的影响

摘要

In this study,the effects of NaCl at different concentrations (0,50,100 and 150 mmol/L) on the growth and osmoregulatory substance accumulation in 60-day-old sugar beet (Beta vulgaris) plants were investigated in pot experiments.The addition of 50,100,and 150 mmol/L NaCl promoted the growth of sugar beet plants and maintained water conditions well.Compared with the control (0 mmol/L),various concentrations of NaCl significantly increased the fresh weights and dry weights of the leaf blade,leaf petiole,and storage root of B.vulgaris plants (P＜0.05).Compared with the control,the high-salt treatment (150 mmol/L) resulted in marked increases in Na+ concentrations in the leaf blade and leaf petiole (4.4-and 4.9-fold,respectively;P＜0.05),and decreased the relative distribution of Na+ in storage roots and lateral roots (by 44％ and 53％,respectively;P＜0.05).The high-salt treatment also reduced the K+ concentrations in the leaf blade and lateral root by 39％ and 55％,respectively (P＜0.05),and increased the relative distribution of K+ in the leaf petiole and storage root by 35％ and 80％,respectively (P＜0.05).The salt treatments reduced sucrose contents by44％-50％ (P＜0.05) and fructose contents in the storage root by 31％-36％ (P＜0.05),whereas glucose contents were unaffected.The high-salt treatment increased the proline concentration in the storage root by 93％,compared with the control (P＜0.05).These results suggested that sugar beet plants can adapt to saline conditions by accumulating the large quantities of Na+ in the leaf blade and leaf petiole,by maintaining K+ homeostasis,and by enhancing the accumulation of proline in storage roots.%采用室内盆栽法,探究了不同浓度NaCl(0、50、100和150 mmol/L)对60 d龄甜菜植株生长及渗透调节物质积累的影响.结果表明,添加50、100和150 mmol/L NaCl明显促进甜菜植株生长,维持良好水分状况.与对照(0mmol/L)相比,不同浓度NaCl均显著增加甜菜叶片、叶柄和贮藏根的鲜重和干重(P＜0.05).高盐(150 mmol/L)条件下,甜菜叶片和叶柄Na+浓度较对照分别增加4.4和4.9倍(P＜0.05),贮藏根和侧根Na+相对分配比例分别降低44％和53％ (P＜0.05);叶片和侧根K+浓度分别降低39％和55％ (P＜0.05),叶柄和贮藏根K+相对分配比例分别增加35％和80％ (P＜0.05).盐处理下贮藏根蔗糖含量降低44％～50％(P＜0.05),果糖含量减少31％～36％(P＜0.05),而葡萄糖含量维持在稳定水平.另外,高盐使贮藏根的脯氨酸浓度较对照增加93％ (P＜0.05).由此可见,甜菜通过叶片和叶柄积累大量Na+、根部维持K+的稳态平衡以及提高脯氨酸含量,以适应盐渍生境.