摘要
【目的】探究NaCl胁迫与根系分泌物成分的关系。【方法】以耐盐和盐敏感两个黄瓜品种为研究对象,NaCl浓度分别为0、100、200和300 mmol.L-1,研究两个黄瓜品种在不同生育期根系分泌物中可溶性糖、氨基酸种类与含量以及其它化合物种类的变化。【结果】定植后50 d,除300 mmol NaCl.L-1处理外,耐盐品种根系分泌物中的可溶性糖含量高于盐敏感品种。从黄瓜根系分泌物中共检测出16种游离氨基酸,定植前耐盐品种的氨基酸种类和含量均高于盐敏感品种;定植后30 d,盐敏感品种在NaCl胁迫下和耐盐品种在100、200 mmol NaCl.L-1浓度下氨基酸总含量低于非NaCl胁迫;各处理氨基酸的种类和总含量在定植后50 d高于定植后30 d,在200、300mmol NaCl.L-1处理下,盐敏感品种氨基酸总含量高于耐盐品种,其它处理为盐敏感品种的氨基酸总含量低于耐盐品种;定植后70 d,氨基酸总含量高于其它两个时期,除300 mmol NaCl.L-1处理,盐敏感品种氨基酸总含量高于耐盐品种。盐敏感品种同一处理的根系分泌物中苏氨酸、丝氨酸、甘氨酸的含量低于耐盐品种,而半胱氨酸的含量高于耐盐品种。GC-MS检测发现,黄瓜根系分泌物中可能存在65种化合物,化合物种类在定植后30 d有高于其它两个时期的趋势,而总含量在定植后50 d有高于其它两个时期的趋势。300 mmol NaCl.L-1处理的盐敏感品种根系分泌物中的化合物总含量在3个取样时期均高于耐盐品种。【结论】根系分泌物中可溶性糖含量的高低受盐胁迫程度以及黄瓜生长时期的影响,盐敏感品种的可溶性糖含量相对较高。盐胁迫可以增加根系分泌物中氨基酸的种类和含量。随着盐胁迫浓度的增加和黄瓜生长时间的延长,各处理GC-MS检出的化合物种类和总含量呈减少的趋势。
【Objective】This study aimed to elucidate the relationship between NaCl stress and root exudates components. 【Method】 Cucumber cultivars with different NaCl tolerances were used as experimental materials. Root exudates components in the whole growth period of cucumber under different NaCl concentrations （0, 100, 200, 300 mmol NaCl？L-1） were analyzed. 【Result】Except for the 300 mmol NaCl？L-1 concentration treatment, soluble sugar content in NaCl-tolerant cucumber root exudates was higher than that in NaCl-sensitive cultivar on 50 d after cucumber transplanting. Sixteen kinds of free amino acids were detected in cucumber root exudates. The variety and contents of free amino acid were higher in NaCl-tolerant cucumber root exudates than in NaCl-sensitive cultivar at the seedlings stage. On 30 d after cucumber transplanting, total amino acid content in NaCl-sensitive cultivar under all concentrations of NaCl and in NaCl-tolerant cultivar under 100 and 200 mmol NaCl？L-1 treatments were lower than that in the control. On 50 d after transplanting, the variety and contents of free amino acid were higher than that on 30 d after transplanting; total amino acids content in NaCl-sensitive cultivar were higher than that in NaCl-tolerant cultivar under 200 and 300 mmol NaCl？L-1 treatments, whereas the trend was the contrary for other NaCl concentrations. On 70 d after transplanting, the variety and contents of free amino acid were higher than that on 30 and 50 d after transplanting, except for the 300 mmol NaCl？L-1 treatment, total amino acids content in NaCl-sensitive cultivar were higher than in NaCl-tolerant cultivar. Under the same NaCl concentration, threonine, serine and glycine contents in the NaCl-sensitive cultivar were higher than in the NaCl-tolerant cultivar, whereas cysteine content was the contrary. There were 65 kinds of compounds were detected in cucumber root exudates with GC-MS method. The variety of these compounds was higher on 30 d after transplanting than on 50 and 70 d after transplanting. The total content of these compounds was higher on 50 d after transplanting than on 30 and 70 d after transplanting. In 300 mmol NaCl？L-1 treatment, the total content of these compounds was higher in NaCl-sensitive cultivar than in NaCl-tolerant cultivar on 30, 50 and 70 d after transplanting. 【Conclusion】Soluble sugar content in cucumber root exudates was affected by NaCl concentration and cucumber growth stage. Soluble sugar content in NaCl-sensitive cultivar was higher than in NaCl-tolerant cultivar. NaCl stress increased the variety of amino acids. The variety and total content of compounds, as detected by GC-MS, had the trend to decrease with the increass of NaCl concentration and cucumber development.
出处
《中国农业科学》
CAS
CSCD
北大核心
2012年第21期4415-4427,共13页
Scientia Agricultura Sinica
基金
国家"973"项目(2009CB119004-5)
国家自然科学基金项目(30771252)
东北农业大学创新团队项目(2007-01)
