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The Screening of the Rice Germplasm Resources on Al Tolerance and the Impact of Different Forms of N Element on Al Tolerance in Rice (Oryza sativa L.)

Author: ShuChang
Tutor: CaiQingSheng
School: Nanjing Agricultural College
Course: Botany
Keywords: rice Al RRE ammonium nitrate
CLC: S511
Type: Master's thesis
Year: 2011
Downloads: 7
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Abstract

Rice is one of the most important crops and about 13% of the rice grow in the acid soil. The toxic effect of aluminum ion is one of the main factors to limit plant growth in acid soil.This experiment was to screen the rice germplasm resources on Al tolerance and study the impact of different forms of N element on Al tolerance, which was divided into three parts. (1) According to the RRE, compare and analyze the Al tolerance of 45 rice to screen the Al resistant specie japonica cv. Longjing9 and indica cv. Aus372 under 50μmol/L Al stress. (2)In the study, japonica cv. Longjing9 with the two rice subspecies, indica cv. Yangdao6 and japonica cv. Wuyunjing7, were compared to study the difference on growth and phisiology under 200μmol/L Al stress. (3)At the same time, indica cv. Yangdao6 and japonica cv. Wuyunjing7, were used to study the impact of different forms of N element on the Al resistance in rice under 200μmol/L Al stress. The main results are as follows:1. The elongation of root is inhibited undet Al stress. According to the result of the relative root elongation (RRE), it was founded that the RRE of japonica cv. Longjing9, Dharial, lgc-1, Ribenyou and Yueguang were the more high under 50μmol/L Al stress and has the better Al tolerance, while the RRE of indica cv. Aus 373 and so on was lower, and the Al resistance of the rest were between them. It is founded that the significantly difference analysis of Japonica and Indica can indicate its RRE of the progency was similar with Indica and the difference was not significant(p<0.05). It means that hybridization is diffcult to get the offspring on Al tolerance. By the comparison with indica cv. Yangdao6 and japonica cv. Wuyunjing7, it was concluded that japonica cv. Longjing9 was the best aluminum resistant specie. It was founded that the nutrient elements absorption of japonica cv. Longjing9 was less affected under Al stress, and its accumulation of Al in root was significantly lower than that of Yangdao6 and there was no significant difference between japonica cv. Longjing9 and Wuyunjing7. Al stress decreased the biomass and increased the content of MDA in root and leaves for Yangdao6, but it did not affect the biomass and the content of MDA in root and leaves for japonica cv. Longjing9. At the same time, Al stress inhibited the growth of the root and reduced the root activity of the three rice varieties. The rate of reduction of the root activity for japonica cv. Longjing9 was 0.54 times as much as that for Yangdao6, and there was no significant difference on the root activities between 09006 and Wuyunjing7 before and after Al treatment. In addition, there was no difference on the Pro content in leaves between japonica cv. Longjing9 and japonica cv.Wuyunjing7 before and after Al treatment. As a result, the experiment further proved that japonica cv. Longjing9 was the best aluminum resistant specie.2. In order to study the impact of different forms of N element on the Al resistance in rice, two rice subspecies, indica cv. Yangdao6 and japonica cv. Wuyunjing7, were taken to study. It was founded that the root morphology, the biomass and the water content in plant was the same as the control under the condition of ammonium. Yangdao6 had a higher level of photosynthetic pigment in leaves, So it had a higher photosynthetic capacity under the condition of ammonium. At the same time, The rate of reduction of the root activity was lower, the content of MDA did not differ with the control, and the Pro content was higher under the condition of ammonium. The two varieties accumulated a higher content of Al, P, K, Ca, Mg and Mn in root, So it strengthen the Al stress under the conditions of nitrate.

The Screening of the Rice Germplasm Resources on Al Tolerance and the Impact of Different Forms of N Element on Al Tolerance in Rice (Oryza sativa L.)

Abstract

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