摘要
盐胁迫环境抑制植物的生长,影响植物组织的离子分布,不同的盐分组成对植物的抑制伤害存在差异,为了研究上海市临港新城滨海盐渍土的生态恢复和重建,模拟该地区的盐分组成,进行了高羊茅(Festuca arundinacea)幼苗的盐胁迫试验。高羊茅种子在非盐胁迫条件下萌发,出苗5d后,进行了不同浓度NaCl:0、50、100、150、200、300、400mmol/L处理,15d后测定生长情况、组织含水量和Na+、K+、Ca2+、Mg2+等离子含量。研究结果表明:盐分对高羊茅幼苗的抑制作用随NaCl浓度增加而加剧,低盐胁迫环境下,幼苗地上部分和根系的鲜重、干重和含水量都与对照没有显著性差异,但是高盐环境严重影响了高羊茅幼苗的生长,而且对地上部分的抑制作用大于根部;盐胁迫影响植物组织的离子分布,Na+浓度持续增加,Ca2+和K+浓度下降,Mg2+含量的影响不大;各组织中K/Na、Ca/Na和Mg/Na随盐胁迫增加而下降。
Salinity stress results in a clear stunting of plants, and disturbances in ion homeostasis. There are many different types of salts and almost an equally diverse set of constraints for plant growth. For ecological reconstruction in the coast of Lingang （30°54＇ N, 121°52＇ E）in Shanghai, the seedling growth and ion distribution in different tissues of Festuca arundinacea were studied in pot experiments, which have the same salt constitute as the coastal saline soil. Seed emergence of Festuca arundinacea was carried out under non-saline environment for about 5 days. A group of different concentrations of NaCl were then added to the pots and the salinity was maintained at 0, 50, 100, 150, 200, 300 mmol/L and 400 mmol/L. The seedling growth, water content, and ions concentration of different tissues were analyzed after 15 days of salt-stress cultivation. A negative relationship between seedling growth and salt concentration was obtained. The flesh weight, dry weight and water content of shoot and root did not decrease significantly in response to low salinity. However, high concentrations of NaCl lead to detrimental effects on the growth of Festuca arundinacea, but the roots of this plant were maintained normally. Ion uptake and homeostasis were disturbed under high salinity. Increased treatment of NaCl induces increase in Na^ ＋ and decrease in Ca^2＋and K^ ＋ levels in the roots and shoots. Mg^2 ＋ concentration in roots and shoots does not vary with the concentration of Na^ ＋. The ratios of K/Na, Ca./Na and Mg/Na in roots and shoots decrease with increased salinity.
出处
《生态学报》
CAS
CSCD
北大核心
2007年第12期5447-5454,共8页
Acta Ecologica Sinica
基金
上海市科委重大攻关基金资助项目(04dz12038)~~
关键词
盐胁迫
高羊茅
幼苗生长
离子平衡
salt-stress
Festuca arundinacea
seeding growth
ion homeostasis
