种子引发对盐胁迫下高粱幼苗生物量分配和渗透物质含量的影响

Effects of seed priming on biomass allocation and osmotic substance contents of sorghum (Sorghum bicolor L.) seedlings under salt stress

以Tx623A×89-363和黑30A×大粒早2个高粱杂交组合为试验材料,100mmol.L-1NaCl溶液对种子进行引发处理。设计0、50、100和150mmol·L-1NaCl溶液模拟盐胁迫,研究种子引发对盐胁迫下高粱幼苗不同器官生物量分配、可溶性物质含量和Na+、K+离子吸收的影响。结果表明:种子引发处理促进了幼苗生长,幼苗总干物质量增加,根系生物量比和根冠比也不同程度增大;150mmol·L-1盐胁迫下,引发处理,Tx623A×89-363根系生物量比、根冠比和总干物质量分别比其未引发处理高5.4%、6.2%和7.5%,黑30A×大粒早总干物质量也比其未引发处理高10.9%,引发处理显著提高了幼苗叶片和根系可溶性糖和脯氨酸的含量;150mmol·L-1盐胁迫下,Tx623A×89-363引发处理幼苗叶片和根系可溶性糖和脯氨酸含量分别比其未引发处理高9.4%、10.0%和8.5%、20.2%,黑30A×大粒早则高4.8%、7.1%和19.3%、26.4%;引发处理还显著降低了2品种幼苗茎叶和根系的Na+/K+值,150mmol·L-1盐胁迫下,Tx623A×89-363幼苗茎叶和根系Na+/K+降低了16.7%和20.6%,黑30A×大粒早降低了5.5%和13.2%。试验结果证明,引发处理在一定程度上提高了高粱幼苗对盐胁迫的适应性,引发处理在品种间产生的效应不同,对弱耐盐性品种效应优于耐盐性品种。

Taking two sorghum hybridized combinations Tx623A×89-363 and Hei30A×Dalizao as test materials,100 mmol·L^-1NaCl solution was used to prime their seeds,and 0,50,100,and 150 mmol·L^-1NaCl solutions were designed for simulating salt stress. The effects of seed priming on the biomass allocation and the soluble substances,Na＋ and K＋ contents in different organs of the sorghum seedlings under salt stress were examined. Seed priming promoted the seedling＇s growth,and increased the total amount of seedling＇s dry matter,root biomass ratio,and root-shoot ratio in various degrees. Under the salt stress of 150 mmol NaCl·L-1,the root biomass ratio,root-shoot ratio,and total amount of dry matter of primed Tx623A×89-363 were 5.4%,6.2%,and 7.5% higher than those of the control,respectively,and the total amount of the dry matter of primed Hei30A×Dalizao was 10.9% higher than that of the control. Seed priming also increased the soluble sugar and proline contents of seedling＇s leaves and roots significantly. Under the salt stress of 150 mmol NaCl ·L-1,the soluble sugar and proline contents in primed Tx623A×89-363 seedling＇s leaves and roots were 9.4% and 10.0%,and 8.5% and 20.2% higher than those of the control,and the contents of these two compounds in primed Hei30A×Dalizao were 4.8% and 7.1%,and 19.3%,26.4% higher than those of the control,respectively. The Na^＋/K^＋ ratio in the seedling＇s stems and leaves and seedling＇s roots of Tx623A×89-363 and Hei30A×Dalizao was significantly reduced by priming. Under the salt stress of 150 mmol NaCl·L-1,the Na^＋/K^＋ ratio in the seedling＇s stems and leaves and seedling＇s roots of Tx623A×89-363 was reduced by 16.7% and 20.6%,and that of Hei30A×Dalizao was reduced by 5.5% and 13.2%,respectively. The results proved that seed priming enhanced the adaptability of sorghum seedlings to salt stress to a certain extent. The effectiveness of seed priming differed with hybridized combinations,being better for the hybridized combination with weaker salt tolerance.