水稻草甘膦耐性浓度的筛选及其生理指标测定

Screening of Glyphosate Concentration and Measuring of Physiological Indexes for Glyphosate-tolerance in Rice

为培育耐草甘膦水稻新品种,本研究以5份辐射和化学诱变育成的耐草甘膦水稻种质为试验材料,进行草甘膦耐性浓度筛选和抗性生理指标测定。结果表明,通过对5份耐草甘膦水稻种质喷施不同浓度(1、2、3和4 g·L-1)的草甘膦,发现喷施4 g·L-1草甘膦可使敏感材料P1003全部死亡,能较好地区分草甘膦耐性和敏感材料;CA21是其中草甘膦耐性最强的水稻种质;随着草甘膦浓度的增加,CA21的莽草酸含量呈下降趋势,丙二醛(MDA)和叶绿素含量则无显著变化,但谷胱甘肽-S-转移酶(GSTs)活性显著增加;随着3 g·L-1草甘膦处理时间的延长,CA21的莽草酸含量无明显变化,MDA和叶绿素含量均呈下降趋势,GSTs活性显著增加。而敏感材料P1003,无论是随着草甘膦浓度的增加,或是随着3g·L-1草甘膦处理时间的延长,其莽草酸和MDA含量均明显增加,叶绿素含量明显下降,GSTs活性则无明显变化。综上,CA21具有耐草甘膦的生理特性,可用于草甘膦耐性分子机制或育种方面的研究。本研究为进一步解析水稻耐草甘膦的分子机理及耐草甘膦水稻育种提供了理论依据。

To breed rice varieties with glyphosate-tolerance,five rice materials developed by radiation and chemical mutagenesis were screened using different glyphosate concentrations. Physiological indexes were measured in glyphosatetolerant and sensitive materials. The five rice varieties were treated with different concentrations of glyphosate（ 1,2,3 and 4 g·L^-1） and found that 4 g·L^-1 of glyphosate could cause the sensitive material P1003 to die completely,which meant a suitable concentration for screening glyphosate-tolerant materials in rice. A line CA21 demonstrated most glyphosate-tolerance in the rice materials. With the increasing concentration of glyphosate,shikimic acid content in CA21 was decreased. No significant change was observed for malondialdehyde（ MDA） and chlorophyll content in CA21. However,glutathione-S-transferases（ GSTs） activity was improved significantly. With the increasing days after the treatment of 3 g·L^-1 glyphosate in CA21,no obvious change was found for shikimic acid content; MDA content and chlorophyll content were decreased,and GSTs activity was improved significantly. However for P1003,whether under glyphosate treatment with different concentrations or with the increasing days after the treatment of 3 g·L^-1 glyphosate,shikimic acid and MDA content were increased significantly,while chlorophyll content was decreased significantly,and GSTs activity had no significant change. In conclusion,CA21 was glyphosate-tolerant and could be further applied in molecular mechanism dissection of glyphosate-tolerance and glyphosate-tolerant breeding. This study provides a theoretical basis for further analysis of the molecular mechanism of glyphosate tolerance in rice glyphosate-tolerant rice breeding.