Cloning and molecular characterization of a gene encoding MAP kinase from maize and its expression in E. coli

A new MAPK gene, ZmSIMK1 （Zea mays L. salt-induced mitogen-activated protein kinase 1）, is isolatod from a maize eDNA library. The full-length ZmSIMK1 gene contains 1636 bp and an open reading frame of 1122 nucleotides capable of eneoding 373 amino acid polypeptides with a predicted molecular mass of 42.3 kda and pI of 6.01. The putative ZmSIMK1 protein contains all 11 conserved subdomains that are characteristics of serine/threonine protein kinases and the TEY motif, which is the putative phosphorylation site. Northern blot analysis shows that ZmSIMK1 is ubiquitously expressed in roots, stems, and leaves of maize seedlings and its mRNA accumulation is observed in maize seedlings treated with 30 mmol/L PEG-6000 and 137 mmol/L NaCl, but the expression of ZmSIMK1 is not significantly affected by 4℃ treatment. The expression vector pET-ZmSIMK1 is constructed by inserting the coding region of ZmSIMK1 eDNA into pET-42a（＋）, and transformed into E. coli strain BL21（DE3）. A 77kda fusion protein is induced by the further culture at 37℃ after addition of 1 mmol/L IPTG.     

Maize transformation via pollen tube pathway and the inheritance of transgene in progeny

The herbicide-resistant gene als was introduced into maize inbred line Qi319 through pollen-tube pathway. The inheritance of transgene was studied up to 33 generation. Transformation was performed by applying plasmid DNA carrying solution on the severed styles after self-pollination, or just prior to selfpoll/nation. After herbicide screening, PCR and Southern blot analysis, seventeen plants were confirmed positive in TO generation, and sixteen of them were self-bred to construct family to 33 progeny. Through PCR analysis and herbicide screening in offspring, four lines were confirmed following a 3 : 1 Mendelian segregation ratio. In other lines the numbers of positive plants were lower than expected. Therefore, it is necessary to select large population in progeny to produce stable inherited lines when transgene was delivered by pollen tube method.     

镉对玉米种子萌发和生长的影响

研究通过不同浓度的Cd^2＋对玉米萌发影响的测试,结果表明,当Cd^2 浓度为0.5mg/L-1.0mg/L时,Ｃd^2 可以促进玉米种子的萌发,提高玉米的发芽势和发芽率,促进玉米芽与幼根的生长,高浓度的Ｃd^2＋不利于玉米萌发和生长。Ｃd^2 对玉米根生长的影响大于对芽生长的影响。     

豉香型米酒特征香气成分研究

采用GC_MS及GC分析手段 ,对广东豉香型米酒的特征香气成分进行鉴定 ,发现 β -苯乙醇及 9,9-二乙氧基壬酸乙酯是其主要特征香气成分 ,通过分析浸泡猪肉的脂肪酸成分变化 ,对这一香气成分产生的机理进行了推导     

Genetic transformation of calli from maize and regeneration of herbicide-resistant plantlets

The herbicide-resistant geneals ofArabidopsis thaliana has been transferred into embryonic calli of maize by microprojectile bombardment. We have obtained chlorsulfuron-resistant calli and regenerated plantlets through selection by herbicide chlorsulfuron. The results of PCR analysis and Southern blotting indicate that geneals has been transferred into some plantlets. The test of spraying chlorsulfuron indicated that the transgenic plantlets had favorable herbicide-resistant trait. The purpose of the research was to obtain chlorsulfuron-resistant transgenic maize and hope that this kind of high efficient herbicide could be widely used in rotation soil of wheat and maize. In addition, through spraying herbicide, we could eliminate the hybrid plants and thereby increase the purity of F1 seeds.     

固定化桔青霉气升式反应器生产核酸酶P1的研究

以玉米芯颗粒吸附桔青霉（Penicillium citrinum）孢子,再用质量分数为1.5%的海藻酸钠包埋吸附固定化细胞玉米芯颗粒,于摇瓶中进行分批培养.实验结果表明在固定化细胞产酶的条件下,培养基中淀粉水解糖浓度为9g/L,蛋白胨浓度为1g/L,采用气升式反应器,产酶发酵周期为50h,发酵液中核酸P1的活力高达8.43mmol     

低醇干白葡萄酒生产工艺的研究

研究了酒度4°左右的低醇干白葡萄酒的生产方法,将白葡萄原汁进行冷冻分离,将冷冻后含糖90g/L的低糖葡萄汁进行皮渣浸提、分离后,用融合子G2发酵至终,用SO2山梨酸进行保藏,可制得酒度4°左右,果香突出的低醇干白葡萄酒.     

硅对汞毒害下玉米种子萌发代谢的影响

研究表明,向含汞污水中加入Na2SiO3能抑制汞引起的玉米种子萌发过程中的淀粉酶、脂肪酶、蛋白酶和呼吸速率的降低,导致种子萌发和幼苗生长恢复.并且随着Na2SiO3浓度的升高,恢复效果愈加明显.     

种植密度对掖单19玉米生理特性和产量的影响

在冀南平原生态条件下 ,通过大田实验 ,研究了不同种植密度对掖单 19玉米生理特性和产量的影响。结果表明 :随着种植密度增加 ,玉米花后果穗叶片的叶绿素含量 (Chl)、光合速率 (Pn)、可溶性蛋白含量下降幅度增大 ,实测产量结果 ,以 6 0株 m2 密度下的产量最高