Effects of non-stomatal components on photosynthesis in soybean under salt stress
2001
A:PS
Details
Title
Effects of non-stomatal components on photosynthesis in soybean under salt stress
Publication Date
2001
Call Number
A:PS
Summary
To elucidate the physiological mechanism of photosynthetic inhibition by salt stress in soyabean (Glycine max), the photosynthetic activity, Na+ accumulation and abscisic acid (ABA) content of two soyabean cultivars, Lee (salt tolerant) and Enrei (salt sensitive), were investigated. After 4 weeks of exposure to various NaCl concentrations (experiment I: 0, 17, 34, 51, 68 and 85 mM; experiment II: 0, 25 and 50 mM), photosynthesis and growth in Enrei were more strongly inhibited by salt stress (50 mM NaCl) than in Lee. The evolution of oxygen was inhibited by salt stress only in Enrei. Therefore, the reduction of photosynthesis in Enrei can be partly explained by the increase in the involvement of non-stomatal components. Since the Na+ concentration in Enrei leaves was increased remarkably under the 50 mM NaCl treatment, it was assumed that a high Na+ content might contribute to non-stomatal components. Lee may also be endowed with some prevention mechanism(s) of Na+ accumulation in shoots, since Lee accumulated more Na+ in roots than Enrei. These results suggested that the difference in salt tolerance between these two soyabean cultivars was due to the inhibition of photosynthesis by non-stomatal components caused by Na+ accumulation in shoots. On the other hand, the leaf ABA content in Lee increased significantly under salt stress, while that in Enrei showed only a slight increase. It is thus possible that ABA enhances salt tolerance in soyabean.
Journal Citation
v.45(1):57-63, JAPANESE JOURNAL OF TROPICAL AGRICULTURE
Contact Information
harvest@worldveg.org
Record Appears in
Research > Published Articles