凝集素类受体蛋白激酶属于类受体蛋白激酶(RLKs)家族,在植物的抗病防御反应、生长发育、胞内信号传导以及非生物胁迫反应过程中发挥重要作用.实验室前期对过表达抗逆转录因子GmNFYB1大豆进行转录组测序,获得了差异表达基因GmLecRlk(Glyma.07G005700),其开放阅读框长度为546 bp,编码181个氨基酸,蛋白结构域分析显示其含有两个丝氨酸/苏氨酸激酶结构域,属于一种G型凝集素类受体蛋白激酶.实时荧光定量PCR结果显示,GmLecRlk基因在大豆的根、茎、叶、荚中均有不同程度的表达,在根中表达量最高;200 mmol/LNaCl处理下,GmLecRlk的mRNA丰度先降低后升高,在12 h时达到最高值,表明该基因参与大豆对盐胁迫的响应.利用发根农杆菌K599获得GmLecRlk过表达转基因发状根复合植株,在盐胁迫处理下,其存活率高于对照;在拟南芥中异源表达GmLecRlk基因,转基因拟南芥在盐胁迫处理下的萌发率、绿化率和根长均高于野生型拟南芥.综上所述,GmLec?Rlk参与大豆对盐胁迫的反应,过量表达基因能提高大豆和拟南芥的耐盐性,为培育和改良抗盐大豆新品种提供新的途径和理论指导.

为了剖析大豆GmCBL10在盐胁迫下的表达模式,本研究采用PCR技术从‘东农50’中克隆了GmCBL10基因全长序列,由792个碱基组成,共编码263个氨基酸.生物信息学分析发现GmCBL10不含信号肽,有一个跨膜结构域和多个磷酸化位点,PSORT预测其定位于细胞质中.在The Bio-Analytic Resource for Plant Biology (Bar)数据库中分析了GmCBL10的拟南芥同源基因AtCBL10在不同非生物胁迫下的表达模式.对GmCBL10的启动子序列进行分析,发现GmCBL10启动子区域含有多种与非生物胁迫应答及生理功能相关的顺式作用元件.对GmCBL10进行系统进化树分析,发现大豆GmCBL10与同为豆科的菜豆、木豆、红豆等的相似性很高.对大豆幼苗进行盐胁迫处理,荧光定量PCR结果显示GmCBL10在盐诱导条件下上调表达,表明GmCBL10可能作为正向调控因子参与大豆的盐胁迫响应.本研究分析了大豆GmCBL10在盐胁迫下的表达差异,为揭示大豆的抗盐机制提供了初步理论依据.

通过PCR的方法从大豆抗菌核病品种Maple Arrow中克隆得到GmGLP10基因,生物信息学分析结果显示GmGLP10蛋白由213个氨基酸组成,具有一个糖基化位点和多个磷酸化位点,为胞外分泌蛋白.通过对GmGLP10基因起始密码子上游1 500 bp序列进行顺式作用元件分析,预测GmGLP10启动子上具有多个与激素和防御胁迫应答相关的顺式作用元件.进化树分析结果表明,GmGLP10与多个生长素结合蛋白进化距离较近,推断其可能具有相似的功能.GmGLP10基因在菌核病菌胁迫下的转录本丰度的变化结果表明在菌核胁迫处理后GmGLP10基因表达量上调明显.GmGLP10可能作为生长素结合蛋白参与调控大豆的生长发育与抗病防御应答反应.

采用室内土箱模拟试验,对不同入渗水头高度、体积质量的垄沟内湿润锋运移特性、入渗速率、灌溉需水量及含水率分布进行了研究.结果表明,相同体积质量条件下,随着入渗水头高度的升高,相同入渗时间湿周长度,湿润锋水平侧渗距离,垂向入渗距离均逐渐增加;水平侧渗距离与垂向入渗距离比值逐渐增大,说明入渗水头越高,水平侧渗距离越远.入渗速率在入渗初期最快,随着时间延长,入渗速率逐渐减小,最后趋于稳定入渗;相同时刻,水头高度越高,入渗速率越快.相同水平侧渗距离条件下,低水头比高水头垂向入渗距离更深;入渗水头越高,土壤体积质量越大,灌溉需水量越少.

为探究不同耕层土壤有机质含量条件下土壤CO2排放通量变化特征与有机质含量关系,设计耕层土壤6个不同有机质含量处理.通过对土壤CO2排放定位连续观测,研究耕层土壤不同有机质含量条件下土壤CO2排放季节变化规律,分析土壤CO2排放与耕层土壤有机质含量关系.结果表明,土壤CO2通量呈单峰曲线季节变化,与地温和气温变化一致;一次方程、二次方程和指数方程均可模拟土壤CO2通量与地温和气温关系,指数方程拟合效果优于一次方程和二次方程.土壤CO2排放最大通量、平均通量、排放总量与耕层土壤有机质呈单峰曲线变化关系,二次方程拟合效果良好;当耕层土壤有机质含量分别为64.50、54.32、59.80 g·kg-1时,土壤CO2排放最大通量、土壤CO2排放平均通量、土壤CO2排放总量达到最大值.

The enantioselective degradation of tebuconazole has been investigated to elucidate the behaviors in agricultural soils, cabbage, and cucumber fruit. Rac-tebuconazole was fortified into three types of agricultural soils and sprayed foliage of cabbage and cucumber, respectively. The degradation kinetics, enantiomer fraction and enantiomeric selectivity were determined by reverse-phase high-performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) on a Lux amylose-2 chiral column. The process of the degradation of tebuconazole enantiomers followed first-order kinetic in the test soils and vegetables. It has been shown that the degradation of tebuconazole was enantioselective. The results indicated that the (+)-S-tebuconazole showed a faster degradation in cabbage, while the (-)-R-tebuconazole dissipated faster than (+)-S-form in cucumber fruit and the test soils.

[Aims] Enantiomeric separation of diniconazole was evaluated under reversed-phase high-performance liquid chromatography with new amylose-tris(5-chlorine-2-methylphenylcarbamate) chiral stationary phase.[Methods] Highperformance liquid chromatography which coupled with amylose-tris(5-chlorine-2-methylphenylcarbamate) chiral stationary phase was used.Elution order of enantiomers was determined by polarimetric detector.The effects of different mobile phase compositions and temperature of column on the chiral separation were investigated.[Results] The result showed that the(-)-diniconazole was eluted firstly through amylose-tris(5-chlorine-2-methylphenylcarbamate) chiral stationary phase.Base line separation was not achieved under any composition of mobile phase with the content of acetonitrile range from 100 to 30% as well as the temperature range from 5 to 45 °C.[Conclusions](-)-(R)-diniconazole was eluted firstly;in terms of retention time and column pressure,best enantiomeric separation of diniconazole achieved with acetonitrile and water(30:70,by vol) and the optimized temperature was 25 °C.Thermodynamical parameters illustrated that enantiomeric separation of diniconazole was driven by enthalpy.