土壤紧实度和盐胁迫对海滨锦葵生长和Na^+·K^+吸收的影响

Effects of Soil Compaction and Salt Stress on Growth and Na^+,K^+ Uptake of Kosteletzkya virginica Seedlings

[目的]为了研究土壤板结和盐胁迫交互作用对海滨锦葵生长及Na+、K+吸收的影响。[方法]在温室大棚内模拟自然条件,研究不同土壤紧实度(1.00、1.20、1.74 g/cm3)和Na Cl盐胁迫(5、10、15、20 g/L)交互作用对海滨锦葵苗期株高、主根长、各构件生物量及Na+、K+吸收的影响。[结果]高土壤紧实度下株高和主根延伸显著受到抑制。土壤紧实度为1.74 g/cm3、盐浓度为20 g/L胁迫下株高和主根长分别是土壤紧实度1.00 g/cm3和盐浓度为5 g/L胁迫下的50.33%和31.45%,叶干重、茎干重、侧根干重、主根干重、根冠比分别为45.45%、42.86%、20.00%、42.86%、76.67%。盐浓度仅对株高和根冠比有显著影响,两者交互作用对海滨锦葵生长没有明显影响。土壤紧实度和盐胁迫对根、茎、叶的Na+、K+吸收均有显著影响,两者交互作用仅对Na+吸收有明显影响。[结论]在海滨锦葵苗期对板结的盐碱土进行松土,是促进其生长的关键环境条件。

[Objective]The research aimed to clarify the effects of soil compaction and salt stress on the growth and the uptake of Na＋and K＋in Kosteletzkya virginica. [Method] Simulated experiments according to natural condition were done in green houoe. The effects of different soil compaction（ 1. 00,1. 20,1. 74 g / cm3） and salt stress（ 5,10,15,20 g/L） on Kosteletzkya virginica seedlings were characterized by the growth indexes of plant height,taproot length and the biomass of organs and the absorption of Na＋and K＋. [Result]Plant height and taproot length were significantly decreased at the highest level of compaction. The combination of 1. 74 g / cm3 compaction and 20 g / L Na Cl resulted in the plant height and taproot length were 50. 33% and 31. 45% of the plants under combination of 1. 00 g / cm3 compaction and 5 g / L Na Cl,respectively. Dry weight of leaf,stem,lateral root,tap root and root / stem ratio were 45. 45%,42. 86%,20%,42. 86% and 76. 67% accordingly. Salt stress had significant effects on plant height and root / stem ratio only. Interaction between compaction and Na Cl had no obvious effects on the growth of seedlings. Soil compaction and salt stress had significantly effects on root,stem and leaf absorption of Na＋and K＋respectively. Both interactions had an obvious effect on Na＋absorption only. [Conclusion] Scarification of hardened salinity soil at seedling stage of Kosteletzkya virginica is the key environmental condition to promote the seedlings growth.