Echinochloa crus-galli is a major weed in rice fields in China,and quinclorac has been long used for its control.Over-reliance of quinclorac has resulted in quinclorac resistance in E.crus-galli.Two resistant(R)E.crus...Echinochloa crus-galli is a major weed in rice fields in China,and quinclorac has been long used for its control.Over-reliance of quinclorac has resulted in quinclorac resistance in E.crus-galli.Two resistant(R)E.crus-galli populations from Hunan,China were confirmed to be at least 78-fold more resistant to quinclorac than the susceptible(S)population.No difference in foliar uptake of 14C-labelled quinclorac was detected between the R and S plants.However,a higher level of 14C translocation and a lower level of quinclorac metabolism were found in the R plants.Basal and induced expression levels ofβ-cyanoalanine synthase(β-CAS)gene andβ-CAS activity were not significantly different between the R and S plants.However,the induction expression of 1-aminocyclopropane-1-carboxylic acid oxidase(ACO1)gene by quinclorac treatment was evident in the S plants but not in the R plants.Quinclorac resistance in the two resistant E.crus-galli populations was not likely to be related to foliar uptake,translocation or metabolism of quinclorac,nor to cyanide detoxification viaβ-CAS.Thus,target-site based quinclorac signal reception and transduction and regulation of the ethylene synthesis pathway should be the focus for further research.展开更多
Echinochloa crus-galli, one of the world＇s most serious weeds, influences seriously the yield and quality of cereal crop plant.It is well known that E.crus-galli grain is dormant, but its dormant type, as well as its...Echinochloa crus-galli, one of the world＇s most serious weeds, influences seriously the yield and quality of cereal crop plant.It is well known that E.crus-galli grain is dormant, but its dormant type, as well as its dormancy release and germination in relation to galactomannan-hydrolysing enzyme activity were poorly understood.The cooperation of endo-β-mannanase（EC 3.2.1.78）, β-mannosidase（EC 3.2.1.25） and α-galactosidase（EC 3.2.1.22） can hydrolyze the cell walls rich in mannan-based polymers.In the present paper, the mature grains are used as experimental materials, we investigated the water uptake of grains, the effect of removing partial endosperm, after-ripening, stratification and phytohormone on grain germination, and the change in endo-β-mannanase, β-mannosidase and α-galactosidase activities of grains during after-ripening and germination.The results showed that the freshly-collected grains were water-permeable and had only phase I and II of water uptake, while the grains after-ripened for 150 d had an obvious phase III of water uptake.In alternating photoperiod, the germination of grains freshly-collected was zero at 10–35°C, and that of half grains was 11% at 20°C only.The grain germination was notably promoted by after-ripening and stratification, but not by gibberellic acid and 6-benzyladenine at 0.0001–1 mmol L–1.β-Mannosidase activity increased during 0 to 300 d of after-ripening and then decreased.The activity of endo-β-mannanase and α-galactosidase of grains decreased with after-ripening.During grain germination, endo-β-mannanase and β-mannosidase activities obviously increased, while α-galactosidase activity decreased.Our data showed that E.crus-galli grain was a deep physiological dormant, the dormancy release by after-ripening was related to an increasing β-mannosidase activity, and its germination was closely associated with an increasing endo-β-mannanase and β-mannosidase activity; which have provided new knowledge to decrease the harm of E.crus-galli on production of cereal crop plant.展开更多
Exserohilum monoceras （Drechsler） Leonard and Suggs is a potential biocontrol agent for the control of Echinochloa species. This fungus causes leaf blight in Echinochloa species, but does not damage rice. Phytotoxic...Exserohilum monoceras （Drechsler） Leonard and Suggs is a potential biocontrol agent for the control of Echinochloa species. This fungus causes leaf blight in Echinochloa species, but does not damage rice. Phytotoxicity of the fungal fermented broth was evaluated through the bioassay and the active ingredients were preliminarily isolated by using silica gel column chromatography （CC） in this study. The most active fraction 5-Ⅲ was obtained and analyzed by gas chromatography-mass spectrometry （GC-MS）. The results show that 5-Ⅲ consisted of many compounds, in which 36 compounds accounted for 94.24% of total peak area. Di-n-butyl phthalate （DBP） displayed the highest activity accounted for 9.24% of the total peak area, suggesting that DBP may be one of the main active compounds produced by E. monoceras.展开更多
采集了浙江、福建、江苏、湖南、湖北、四川、重庆、黑龙江、河南9个省的稗(Echinochloa crus-galli(L.)P.Beauv.)及其变种的33份种子,分别播种在相同的环境下,获得33个种群,测定了种群的16个形态性状,筛选出重复性好的9条ISSR引物,从3...采集了浙江、福建、江苏、湖南、湖北、四川、重庆、黑龙江、河南9个省的稗(Echinochloa crus-galli(L.)P.Beauv.)及其变种的33份种子,分别播种在相同的环境下,获得33个种群,测定了种群的16个形态性状,筛选出重复性好的9条ISSR引物,从33个种群中扩增出了109个位点。基于这些形态性状和ISSR位点信息,对33个种群先进行主成分分析,在此基础上再进行模糊均值聚类分析,探讨了它们的形态和遗传变化特点,及其与形态—遗传—地理背景三者之间的关系。主要结论如下:(1)33个种群可以鉴别出形态性状相对一致的4组,能够识别出西来稗(E.crus-galli var.zelayensis(Kunth)Farw.)、无芒稗(E.crus-galli var.mitis(Pursh)Peterm.)、细叶旱稗(E.crus-galli var.praticola Ohwi);(2)基于109个位点信息对33个种群进行聚类分析得到了6组,部分组与形态聚类分组有一定的对应性;(3)33个稗草种群的遗传分化受地理背景因素的影响(r=0.684,n=33,P<0.001);形态变异也有较明显的遗传背景因素(r=0.425,n=33,P<0.02)。在相对一致的稻田生境中,可能存在着形态上的趋同适应,使遗传上分化的组间在形态上又往往有交叉过渡,致使稗原变种(E.crus-galli var.crus-galli)、西来稗、无芒稗、短芒稗(E.crus-galli var.breviseta(D9ll)Podp.)在形态上难以区别;(4)基于遗传和形态数据分析,发现细叶旱稗无论在形态上,还是遗传上,均形成了明显的一组,推测与该种长期适应于干旱生境有关,建议将细叶旱稗提升为种的水平,并将其命名为Echinochloa praticola(Ohwi)Guo S L,Lu Y L,Yin L P&Zou M Y。展开更多
目的:克隆1,4-α-葡聚糖分支酶1(GBE1)基因,并对其编码蛋白进行生物信息学以及差异表达分析。方法:根据家鸡转录组数据,利用PCR扩增GBE1的全长cDNA并进行生物信息学分析。使用qRT-PCR法检测基因在家鸡6个组织中的表达差异。结果:克隆得...目的:克隆1,4-α-葡聚糖分支酶1(GBE1)基因,并对其编码蛋白进行生物信息学以及差异表达分析。方法:根据家鸡转录组数据,利用PCR扩增GBE1的全长cDNA并进行生物信息学分析。使用qRT-PCR法检测基因在家鸡6个组织中的表达差异。结果:克隆得到全长为2145 bp GBE1基因,开放阅读框(ORF)为2130 bp,编码709个氨基酸。GBE1蛋白相对分子质量为81.993,理论等电点6.25,稳定指数为35.40,平均亲水性值为-0.484,属于稳定酸性亲水蛋白;GBE1蛋白含有67个磷酸化位点,不存在跨膜区域与信号肽序列,主要定位在细胞质、细胞核、线粒体、胞液中;二级结构主要包括α-螺旋、β-折叠、无规则卷曲和延伸链,三级结构表明为单体蛋白;同源性分析表明,家鸡中GBE1蛋白氨基酸序列与珠鸡亲缘关系最近。qRT-PCR结果表明,GBE1基因在家鸡心、肝、脾、肺、肾、鸡内金6个组织内均有表达,但在肝脏和鸡内金中的表达量显著高于其他脏器。结论:该结果为进一步探讨家鸡GBE1基因的功能及其对葡聚糖分支酶的调控机制积累了必要的研究基础。展开更多
基金financially supported by the National Natural Science Foundation of China (Grant Nos. 31701803 and 31772182)the Natural Science Foundation of Hunan Province (Grant No. 2017JJ3164) in China and the Australian Grains Research and Development Corporation (GRDC)
文摘Echinochloa crus-galli is a major weed in rice fields in China,and quinclorac has been long used for its control.Over-reliance of quinclorac has resulted in quinclorac resistance in E.crus-galli.Two resistant(R)E.crus-galli populations from Hunan,China were confirmed to be at least 78-fold more resistant to quinclorac than the susceptible(S)population.No difference in foliar uptake of 14C-labelled quinclorac was detected between the R and S plants.However,a higher level of 14C translocation and a lower level of quinclorac metabolism were found in the R plants.Basal and induced expression levels ofβ-cyanoalanine synthase(β-CAS)gene andβ-CAS activity were not significantly different between the R and S plants.However,the induction expression of 1-aminocyclopropane-1-carboxylic acid oxidase(ACO1)gene by quinclorac treatment was evident in the S plants but not in the R plants.Quinclorac resistance in the two resistant E.crus-galli populations was not likely to be related to foliar uptake,translocation or metabolism of quinclorac,nor to cyanide detoxification viaβ-CAS.Thus,target-site based quinclorac signal reception and transduction and regulation of the ethylene synthesis pathway should be the focus for further research.
基金supported by grants from the National Science and Technology Support Program of China(2012BAC01B05)
文摘Echinochloa crus-galli, one of the world＇s most serious weeds, influences seriously the yield and quality of cereal crop plant.It is well known that E.crus-galli grain is dormant, but its dormant type, as well as its dormancy release and germination in relation to galactomannan-hydrolysing enzyme activity were poorly understood.The cooperation of endo-β-mannanase（EC 3.2.1.78）, β-mannosidase（EC 3.2.1.25） and α-galactosidase（EC 3.2.1.22） can hydrolyze the cell walls rich in mannan-based polymers.In the present paper, the mature grains are used as experimental materials, we investigated the water uptake of grains, the effect of removing partial endosperm, after-ripening, stratification and phytohormone on grain germination, and the change in endo-β-mannanase, β-mannosidase and α-galactosidase activities of grains during after-ripening and germination.The results showed that the freshly-collected grains were water-permeable and had only phase I and II of water uptake, while the grains after-ripened for 150 d had an obvious phase III of water uptake.In alternating photoperiod, the germination of grains freshly-collected was zero at 10–35°C, and that of half grains was 11% at 20°C only.The grain germination was notably promoted by after-ripening and stratification, but not by gibberellic acid and 6-benzyladenine at 0.0001–1 mmol L–1.β-Mannosidase activity increased during 0 to 300 d of after-ripening and then decreased.The activity of endo-β-mannanase and α-galactosidase of grains decreased with after-ripening.During grain germination, endo-β-mannanase and β-mannosidase activities obviously increased, while α-galactosidase activity decreased.Our data showed that E.crus-galli grain was a deep physiological dormant, the dormancy release by after-ripening was related to an increasing β-mannosidase activity, and its germination was closely associated with an increasing endo-β-mannanase and β-mannosidase activity; which have provided new knowledge to decrease the harm of E.crus-galli on production of cereal crop plant.
基金the National Natural Science Foundation of China(30671381,30671381)Guangdong Provincial Natural Science Foundation of China(06300411)for the financial supports
文摘Exserohilum monoceras （Drechsler） Leonard and Suggs is a potential biocontrol agent for the control of Echinochloa species. This fungus causes leaf blight in Echinochloa species, but does not damage rice. Phytotoxicity of the fungal fermented broth was evaluated through the bioassay and the active ingredients were preliminarily isolated by using silica gel column chromatography （CC） in this study. The most active fraction 5-Ⅲ was obtained and analyzed by gas chromatography-mass spectrometry （GC-MS）. The results show that 5-Ⅲ consisted of many compounds, in which 36 compounds accounted for 94.24% of total peak area. Di-n-butyl phthalate （DBP） displayed the highest activity accounted for 9.24% of the total peak area, suggesting that DBP may be one of the main active compounds produced by E. monoceras.
文摘采集了浙江、福建、江苏、湖南、湖北、四川、重庆、黑龙江、河南9个省的稗(Echinochloa crus-galli(L.)P.Beauv.)及其变种的33份种子,分别播种在相同的环境下,获得33个种群,测定了种群的16个形态性状,筛选出重复性好的9条ISSR引物,从33个种群中扩增出了109个位点。基于这些形态性状和ISSR位点信息,对33个种群先进行主成分分析,在此基础上再进行模糊均值聚类分析,探讨了它们的形态和遗传变化特点,及其与形态—遗传—地理背景三者之间的关系。主要结论如下:(1)33个种群可以鉴别出形态性状相对一致的4组,能够识别出西来稗(E.crus-galli var.zelayensis(Kunth)Farw.)、无芒稗(E.crus-galli var.mitis(Pursh)Peterm.)、细叶旱稗(E.crus-galli var.praticola Ohwi);(2)基于109个位点信息对33个种群进行聚类分析得到了6组,部分组与形态聚类分组有一定的对应性;(3)33个稗草种群的遗传分化受地理背景因素的影响(r=0.684,n=33,P<0.001);形态变异也有较明显的遗传背景因素(r=0.425,n=33,P<0.02)。在相对一致的稻田生境中,可能存在着形态上的趋同适应,使遗传上分化的组间在形态上又往往有交叉过渡,致使稗原变种(E.crus-galli var.crus-galli)、西来稗、无芒稗、短芒稗(E.crus-galli var.breviseta(D9ll)Podp.)在形态上难以区别;(4)基于遗传和形态数据分析,发现细叶旱稗无论在形态上,还是遗传上,均形成了明显的一组,推测与该种长期适应于干旱生境有关,建议将细叶旱稗提升为种的水平,并将其命名为Echinochloa praticola(Ohwi)Guo S L,Lu Y L,Yin L P&Zou M Y。
文摘目的:克隆1,4-α-葡聚糖分支酶1(GBE1)基因,并对其编码蛋白进行生物信息学以及差异表达分析。方法:根据家鸡转录组数据,利用PCR扩增GBE1的全长cDNA并进行生物信息学分析。使用qRT-PCR法检测基因在家鸡6个组织中的表达差异。结果:克隆得到全长为2145 bp GBE1基因,开放阅读框(ORF)为2130 bp,编码709个氨基酸。GBE1蛋白相对分子质量为81.993,理论等电点6.25,稳定指数为35.40,平均亲水性值为-0.484,属于稳定酸性亲水蛋白;GBE1蛋白含有67个磷酸化位点,不存在跨膜区域与信号肽序列,主要定位在细胞质、细胞核、线粒体、胞液中;二级结构主要包括α-螺旋、β-折叠、无规则卷曲和延伸链,三级结构表明为单体蛋白;同源性分析表明,家鸡中GBE1蛋白氨基酸序列与珠鸡亲缘关系最近。qRT-PCR结果表明,GBE1基因在家鸡心、肝、脾、肺、肾、鸡内金6个组织内均有表达,但在肝脏和鸡内金中的表达量显著高于其他脏器。结论:该结果为进一步探讨家鸡GBE1基因的功能及其对葡聚糖分支酶的调控机制积累了必要的研究基础。
