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Effect of Salt Stress on Seed Germination and Seedling Growth of Rice

Author: LiWei
Tutor: TaoLongXing
School: Chinese Academy of Agricultural Sciences
Course: Crop
Keywords: Rice Seed Seedling Salt stress Resistant salt
CLC: S511
Type: Master's thesis
Year: 2011
Downloads: 368
Quote: 1
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Abstract

In the test, NaCl and NaHCO3 were used as salt stress, several different salt concentration gradients were set, seeds of indica rice and japonica rice were treated with salt stress, seed germination and seedling growth of the various agronomic parameters and physiological and biochemical indexes were measured under different treatments, inherent relativity of seed germination and seedling physiological factors were discussed. in order to clear reason of salt stress effect on rice seed and seedling growth and development. This would provide theoretical basis on scientific planting rice on saline alkali soil, on selecting seed which had high-quality resistant salt and increased yield, and provide reference index of resistance breeding of rice. The test results were as follows.1. Low concentration of salt stress slightly simulated effect on germination of rice seed. Germination of rice seed showed inhibitory effect when more than 1% salt concentration. Germination rate of different varieties was slightly influenced when less than 0.5% salt concentration; and germination rate of different varieties was more and more lower along with the increasing of salt concentration when more than 0.5% salt.0.7% salt concentration was critical concentration which germination rate showed differences on strong and low resistant salt varieties. When more than 0.7% salt concentration, germination rate of varieties which were weak resistant salt would decrease quickly, and germination rate of varieties which were strong resistant salt would gently decreased. Effects of salt stress on impact law of other germination stage indicators were similar to bud rate.2. Effect law of salt stress on agronomic traits of plant height, root length, root number of rice seedling was consistent. Low concentrations of salt stress would promote growth agronomic traits of rice seedling, and high concentrations of salt stress would inhibit growth. Plant height, root length, root number value of varieties which were strong resistant salt were significantly better than other varieties, when the salt concentration was high, the differences were more pronounced. Change situation of plant height, root length, root number and other agronomic traits indexes when rice was salt resistance could be used as the basis of salt resistant ability.3. Effect law of salt stress on physiological and biochemical indexes of riceVarieties which were weak resistant salt were high exosmosis conductivity, affected more degree hurt salt resistance.However, Varieties which were strong resistant salt were low exosmosis conductivity, affected smaller degree hurt salt resistance. Extravasais conductivity was inversely proportional with salt resistance of rice.As concentration salt stress increased, the proline content, SOD activity, MDA content of varieties leaves of rice seedling increased significantly, while the soluble sugar content, chlorophyll content decreased.leaves of rice seedling of varieties which were strong resistant salt were high proline content, SOD activity, soluble sugar content, the chlorophyll content, were low MDA content. Leaves of rice seedling of varieties which were weak resistant salt were low proline content, SOD activity, soluble sugar content, the chlorophyll content, were high MDA content.

Effect of Salt Stress on Seed Germination and Seedling Growth of Rice

Abstract

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