“粉玉”体色瓯江彩鲤MHC class Ⅱ B基因多态性及其与鱼体抗病力的关系

利用1对特异性引物DABF和DABR,分别从30尾感病和13尾抗病"粉玉"体色瓯江彩鲤(Cyprinus carpiovar.color)的cDNA中扩增出长度为624 bp的MHC classⅡB基因片段。对210个有效克隆进行测序,获得84个不同的编码序列,分属13个不同的等位基因,其中Cyca-DAB3*17和Cyca-DAB3*18为新发现的2个等位基因。核苷酸、氨基酸变异位点总数为267、130,变异率较高(42.79%、62.50%)。MHCⅡB基因片段包括第1 4个外显子,分别编码信号肽、β1和β2结构域及跨膜区。β1结构域的变异明显大于β2结构域,表现为在长度为276 bp的β1结构域中,核苷酸、氨基酸变异位点分别为150个(54.35%)和72个(78.26%);而长度为282 bp的β2结构域的核苷酸、氨基酸变异位点较少,分别为105个(37.23%)和54个(57.45%)。在β1结构域的24个抗原结合位点(PBR)上,有22个发生了变异。β1结构域的PBR、非抗原结合位点(non-PBR)及β2结构域的非同义碱基替换率(dN)与同义碱基替换率(dS)的比值ω分别为1.366、0.992、0.792,表明"粉玉"体色瓯江彩鲤MHC classⅡB基因的β1结构域在进化过程中受到正向选择作用。基因Cyca-DAB3*09在抗病群体中出现的频率(7.81%)显著高于感病群体(1.37%,P<0.05),新等位基因Cyca-DAB3*18(频率为3.13%)只出现在抗病群体中,基因Cyca-DAB1*08、Cyca-DAB3*08和Cyca-DAB3*17为感病群体所特有。研究结果为抗病"粉玉"体色瓯江彩鲤的选育奠定了基础。

北京日光温室“粉玉”草莓栽培技术

为了发展特色草莓产业,北京引进国产高品质草莓品种“粉玉”系列进行日光温室促成栽培。11月下旬果实可成熟,比“红颜”品种提早采收10~15 d,可溶性固形物含量可达13.1%~18.0%,单果质量30 g,667 m^(2)产量为2288 kg、效益为7.8万元。

与“全红”瓯江彩鲤体色相关的SRAP及SCAR分子标记

利用相关序列扩增多态性(Sequence Related Amplified Polymorphism,SRAP)技术分析"全红"和"粉玉"瓯江彩鲤,筛选与瓯江彩鲤体色相关的分子遗传标记。从88个SRAP引物组合筛选出的12个引物组合共获得扩增条带104个,并筛选出1个SRAP特异扩增带,即"全红"瓯江彩鲤家系SR2,7173 bp带。该条SRAP特异扩增条带经回收、克隆和测序,并将测序结果进行BLAST分析,发现该片段在GenBank中与斑马鱼的POl多蛋白基因和尿红素基因有较高的同源性。根据序列信息分别设计了4对正、反向引物(22—26 bp)。用4对引物分别在"全红"瓯江彩鲤F2和"粉玉"瓯江彩鲤F2群体中进行PCR扩增,仅发现SC-3(154 bp)能够在"全红"瓯江彩鲤群体中特异扩增,而且在"粉玉"瓯江彩鲤F2群体中未出现此扩增带。采用大样本对该SC-3标记进行验证,结果发现,在"全红"瓯江彩鲤群体中呈现阳性,而在"粉玉"瓯江彩鲤群体中为阴性,可以区分这两种群体。因此SC-3标记可以作为"全红"瓯江彩鲤群体一个重要的分子遗传特征指标,为进一步进行分子标记辅助育种奠定了基础。

Effects of Feeding Corn Stalks on Economic Indicators of Tenebrio molitor

[Objective] The study aimed at reducing the economic cost in feeding Tenebrio molitor and improving the utilization ratio of corn stalks.[Method] The effects of different proportions of corn stalks on the weigh of Tenebrio molitor and the contents of crude protein,crude fat,Ca,P,dry matter and crude ash in the half-dry matter of Tenebrio molitor had been studied in the laboratory.[Result] Compared with the recipes of all wheat bran and pure fine fodder,feeding Tenebrio molitor by applying 30%-60% of corn stalks could significantly improve the content of crude protein in the half-dry materials of Tenebrio molitor,but it was detrimental to the improvement in weight of Tenebrio molitor and the accumulation of crude fat.To be specific,the recipe V（50% of corn stalks ＋ 50% of fine fodder） was beneficial to the accumulation of dry matter and crude ash.The recipe VII（70% of corn stalks ＋ 30% of fine fodder） and the recipe VIII（70% of corn stalks treated with Guangda feed leaven ＋ 30% of fine fodder） were beneficial to the accumulation of crude protein,Ca and P.There were differences among the influences of corn stalks in different treatments on the crude protein and other nutrition indicators of Tenebrio molitor.[Conclusion] Appropriately applying corn stalks can improve the accumulation of the crude protein,crude ash,dry matter,Ca and P of Tenebrio molitor but was detrimental to the growth and development of Tenebrio molitor and the accumulation of crude fat.

Research on Laws of Starch Accumulation in Micro-endosperm Maize Kernel

[Objective] The experiment aimed to study laws of accumulation of starch in micro-endosperm maize kernel. [Method] The laws of accumulation of starch in maize embryo and OSK(the other section of a kernel except embryo) of MEM(micro-endosperm maize) were studied in this experiment by taking Gaoyou 115 maize as control. [Result] The starch accumulation speed of MEM embryo was slightly lower than that of Gaoyou115 and the starch accumulation speed of MEM OSK was far lower than that of Gaoyou 115, so the starch content of the whole kernel of Gaoyou 115 was 3.4 to 4.5 times as high as that of MEM during harvesting. The embryo starch weight ration of Gaoyou 115 maize during harvesting was only 3% to 4% while that of MEM was 16% to 22%. Moreover, starch accumulation speeds of different MEM materials were different and there were significant differences in starch content during harvesting among different MEM materials. [Conclusion] The starch accumulation in MEM was slow, and MEM has widely variation on starch accumulation.

Optimization of Hydrolysis Conditions for Corn Gluten Meal

[Objective] To investigate the optimal enzyme for the hydrolysis of corn gluten meal and the optimal hydrolysis conditions for the enzyme. [Method] Nine kinds of enzymes were used to hydrolyze the corn gluten meal, using the formaldehyde titration method for the determination of hydrolysis degree, and orthogonal test was used to determine the optimal hydrolysis conditions for double enzymes hydrol- ysis of corn gluten meal. [Result] The optimal pretreatment condition for corn gluten meal is heating at 121 ~C for 30 min. The double enzyme hydrolysis for the pro- treated corn gluten meal using 2709 alkaline protease and flavourzyme showed that the degree of hydrolysis could reach 32.4% with enzyme addition amount of 4%, hy- drolysis time of 4 h at 45℃ and pH=7.0. [Conclusion] This study laid the foundation for the study on the preparation of bioactive peptides such as oligopeptide with high F value and antihypertensive peptides, further improving the corn intensive process- ing industrial chain.

Effects of Synchronous Pollination on Growth of Maize Kernels at the Tip of Ear

Under natural pollination （NP）, early-fertilized ovaries at the base of ear promote kernel abortion of late-fertilized ovades from the tip in maize （Zea mays L.）. Synchronous pollination （SP） improves maize kernel set, but the physiological masons behind this response are yet unclear. We e^amined maize kernel growth at the tip of ear subjected to NP or SP with different ~.ant density of 6 plants/rr~ or 9 plants/n~. Synchronous pollination of ears baged before silking was obtained by hand pollination on 3 days after silking （DAS） and samples were taken from natural and hand-pollinated ears on 8, 13, 18, and 23 DAS. At each sampling date, kemel fresh weight, volume and dry weight at the tip of ear were all higher for maize grown under SP than NP, and the contents of soluble sugar, sucrose, starch, nitro- gen and the ratios of soluble sugar to nitrogen （C/N） in kernel at the tip of ear were all higher too for maize grown under SP than NP.

Application Effects of Ultra-fine Powder Shaped Maize Seed Coating Agent in Spring Sowing areas in northeast China

The research explored adaptability maize seed coating agent in spring sowing and effects of ultra-fine powder shaped areas in northeast China. The results showed that germination potential and rate both improved around 5% and the num- ber of root increased by 4% in the treatments with ultra-fine powder shaped maize seed coating agent compared with the control group without seed coating. What＇s more, the treatments with ultra-fine powder shaped maize seed coating agent took advantages in terms of fresh weight of seeding, stem diameter, and dry weight. It is notable that control effects on underground insects performed the best, with per- centage over 94%, which is more excellent relative to other agents in markets. Therefore, ultra-fine powder shaped maize seed coating agent can be widely applied in spring sowing areas in northeast China, without side effects.

A New Rapid and Batch-oriented Crushing Method for DNA Extraction from Maize Leaves

The crushing of leaves is the most time and effort-consuming part in DNA extraction which is a fundamental step in the study of molecular biology. In this study, a new rapid and batch-oriented crushing method for DNA extraction from maize leaves was developed. In addition, the practicability of the developed method in molecular marker-assisted breeding was verified using SSR molecular maker technology so as to provide a rapid, batch-oriented, low-cost and non-toxic leafcrushing method for a large number of molecular marker tests, improving test efficiency.

Structure, Physico-chemical and Microbiological Properties of Ozone-oxidized Wheat, Corn, Potato and Rice Starches

A limited number of studies have been conducted on the effects of ozone use on cereal and its components. Starch, an important natural macromolecule, is an essential component of cereals. In present study, the effects of ozone on the structure, physico-chemical and microbiological properties of wheat, corn, potato and rice starches were investigated. Wheat starch, corn starch, potato starch and rice starch water mixtures were prepared in the ratio of 1：9 （dry sample to water ratio） and treated with ozone at a rate of 60 g/h for 1 hour, while unozonated samples were used as controls. Light microscopy represented that the structures of corn and potato starch samples were affected by 1 hr ozonation rather than the structures of wheat and rice starch samples. Colour of ozone-oxidized wheat, corn and potato starch samples could meet the consumer preference due to the higher lightness, higher whiteness and lower chroma value. However, high chroma, high yellownes and low whiteness values of ozonated rice starch is not adequate for consumer desire. Microbiological analysis showed that 1 hr ozonation reduced the total bacteria and mould/yeast counts significantly for all wheat, corn, potato and rice starch samples （P 〈 0.05） due to most probably the reduced pH of samples. Ozonation can be an alternative modification technique, but further research is needed to understand the certain benefits and limitations of ozone applications on starch oxidation for human safety and health.

Construction of Maize Universal Expression Vector PGM-35Sbar and Maize Transformation

[Objective] The paper was to construct maize universal expression vector, in order to provide basis for using transgenic methods to improve abiotic stress tolerance of maize. [Method] Based on the transformation of existing pGreen0229 plant expression vector, phosphinothricin-resistant selectable marker-bar gene driving by CaMv35S promoter was constructed, which could be used to connect target gene of maize expression vector PGM-35Sbar, and transform Ji444 maize inbred lines by pollen tube pathway. [Result] The universal expression vector for PGM-35Sbar maize had been successfully constructed. When the maize plants were transformed, 14 resistant plants were obtained, and 12 plants were identified to be positive plants by PCR detection. [Conclusion] The study provided basis for rapid construction of maize expression vector containing specific target gene.

Transgenic Maize Plants Obtained by Pollen-mediated Transformation

The genetic transformation was achieved by pollen_mediated approach on maize ( Zea mays L.) inbred lines Tai 9101 and Zong 31. Plasmid DNA of pGLⅡ_RC_1 was mixed with fresh pollen of maize inbreds in sucrose solution. The pollens were treated by ultrasonication and collected, pollinated on silks of maize ears. Transformants were confirmed by dot blot hybridization, PCR amplification and PCR_Southern blot hybridization. The pollen_mediated transformation approach could circumvent the tedious tissue culture procedures like in particle bombardment and Agrobacterium infection, etc. This approach is simple, easy to operate, and could be widely used in practice.

Preparation and sintering properties of zirconia-mullite-corundum composites using fly ash and zircon

Zirconia-mullite-corundum composites were successfully prepared from fly ash,zircon and alumina powder by a reaction sintering process.The phase and microstructure evolutions of the composite synthesized at desired temperatures of 1 400,1 500 and 1 600°C for 4 h were characterized by X-ray diffractometry and scanning electronic microscopy,respectively.The influences of sintering temperature on shrinkage ratio,apparent porosity and bulk density of the synthesized composite were investigated.The formation process of the composites was discussed in detail.The results show that the zirconia-mullite-corundum composites with good sintering properties can be prepared at 1 600°C for 4 h.Zirconia particles can be homogeneously distributed in mullite matrix,and the zirconia particles are around 5μm.The formation process of zirconia-mullite-corundum composites consists of decomposition of zircon and mullitization process.

Pollen Xenia Effect of High-oil Maize on Kernel Traits of Common Maize

[Objective] This study aimed to investigate the effects of high-oil maize pollen on kernel traits of common maize, so as to provide some basis for the production and quality improvement of high-oil maize. [Method] Three hightoil maize varieties were cultivated to pollinate three common maize varieties. [Result] The kemel yield of common maize was increased or changed slightly, and the embryo weight was increased significantly after they were pollinated with the pollen of hightoil maize. The kemel embryo percentage and protein content of common maizethigh oil maize hybrids were higher than those of common maize inbreds. [Conclusion] The growth and development of kernel embryos, as well as the kernel quality of common maize was improved by pollination with hightoil maize.

Kinetics of decomposition of mullite and corundum in coal fly ash under highly alkaline condition

Decomposition kinetics of mullite and corundum in coal fly ash with highly alkaline solution was studied.The effects of the reaction temperature and reaction time on decomposition rates of mullite and corundum and alumina extraction efficiency were investigated.The results show that increasing reaction temperature and reaction time increases the decomposition rates of mullite and corundum and alumina extraction efficiency,with the decomposition temperature of mullite lower than that of corundum.After 90 min reaction at 220℃,more than 100 g alumina was extracted when recycling 1 L of alkaline solution.The decomposition processes of mullite and corundum corresponded with the shrinking unreacted core model,and the reaction rate was under chemical reaction control,with the activation energies of mullite and corundum being 67.46 and 161.82 kJ/mol,respectively.

Effects of Dietary Carbohydrates Sources on Lipids Compositions in Abalone, Haliotis discus hannai Ino

A study was conducted to evaluate the effects of dietary carbohydrates on triglyceride, cholesterol and fatty acid concentrations in abalone, Haliotis discus hannai Ino. Six semi-purified diets with different carbohydrates （dextrin, heat-treated wheat starch, wheat starch, corn starch, tapioca starch and potato starch, respectively）, all containing a carbohydrate level of 33.5%, were fed to abalone （initial shell length： 29.98mm±0.09mm; initial weight. 3.42g±0.02g） for 24 weeks in a recirculation system. The results indicate that serum triglyceride concentrations were significantly （P〈0.05） higher in the abalone fed with dextrin, heat-treated wheat starch and wheat starch than those fed with corn starch, and serum cholesterol concentrations were significantly （P〈0.05） higher in the abalone fed with dextrin, heat-treated wheat starch than those fed with corn starch. Fatty acid C20：4n-6 in the foot mus- cles were significantly （P〈0.05） lower in the abalone fed with dextrin than those fed with wheat starch, corn starch, tapioca starch and potato starch. Fatty acid C20：4n-6 in hepatopancreas was significantly （P〈0.05） lower in abalone fed with heat-treated wheat starch than those fed with corn starch, tapioca starch and potato starch. Fatty acid C22：6n-3 in the foot muscles were significantly （P 〈 0.05） lower in the abalone fed with dextrin and beat-treated wheat starch than those fed with wheat starch and potato starch.

Non-starch Polysaccharide Degrading Enzymes in Corn and Wheat-Based Broiler Diets： Dual Activity for Major Substrates

This study consolidates the efficacy of a non-starch polysaccharide （NSP）ase enzyme-concept in corn and wheat-based broiler diets. The NSP building blocks of corn, wheat and soybean meal （SBM, 44% protein） were studied first. Cereal NSP primarily consists of arabinose, xylose and glucose molecules that form arabinoxylan, β-glucan and cellulose polysaccharides. In soybean meal （SBM）, glucose （cellulose） predominates, next to galactose and uronic acids that form “pectins”. Broiler performance progress using in-feed NSPase enzymes depends on the concentration, complexity and solubility of the substrate and the genetic potential of the animal, mainly. A dual NSPase enzyme-concept for cereal and SBM NSP, predominantly being arabinoxylan, β-glucan and cellulose, was developed. Methods for measuring enzyme activities （endo-1,4-β-xylanase （EC 3.2.1.8） and endo-1,3（4）-β-glucanase （EC 3.2.1.6）） were developed （AVEVE Biochem UNITS） and preparations thereof （XG） standardized to meet requirements for most challenging NSP （corn, barely soluble）. Feed intake （FI）, bodyweight gain （BWG） and feed：gain ratio （F：G） were assessed in three zootechnical studies, each using 160 Ross 308 broilers split in two feeding groups with 80 birds/group （10 replicates of eight） for 42 d （starter/grower period）. Respective corn-SBM, wheat-SBM and corn/wheat-SBM diets were used as negative control （NC） or added with the enzyme-concept （XG）. In the total period, XG ameliorated BWG and F：G compared to NC in each study, where BWG increased best in diets with corn and F：G lowered most in diets with wheat. The dual NSPase enzyme-concept offers ingredient flexibility in present setting by enhancing the nutritional content of corn, wheat and SBM, expectedly from cleaving major NSP target molecules. Thereby, broiler professionals increase feed formulation liberty and safety and production result simultaneously.

Impact of Nitrogen Fertilization on the Oil, Protein, Starch, and Ethanol Yield of Corn （Zea mays L,） Grown for Biofuel Production

Nitrogen fertilization is one of the greatest challenges associated with the production of biofuel from corn grain. The objective of this research was to determine the effect of N fertilization on the content and yield of oil, protein, and starch in corn grain. The project was done in Southeast Missouri （USA）, from 2007 to 2009 in a silt loam soil. Corn grain contains 3.8-4.2% oil, 6.7%-8.9% protein, 68.0%-70.4% extractable starch, and 76.0%-77.7% total starch. The total starch yield ranged from 2.8 to 7.8 mg.ha1 whereas the extractable starch varied between 2.5 to 7.1 mg-ha1. As the N rate went up, the oil and starch content of the grain decreased, whereas the protein content and the protein, starch, and oil yields increased, reaching their maximum at the N rate corresponding to 179.0 kg N.ha~. The potential ethanol yield varied between 616.2 and 7,035.1 L-ha1 depending on the method of conversion of the starch into ethanol, the year and the N rate （P 〈 0.0001）. The negative correlation between N fertilization rate and starch content suggested that when farmers add too much N to their soil to increase grain yield, they reduce the starch content in those grains, and consequently the conversion into bioethanol. Therefore, for biofuel production to be beneficial for both farmers and the power plant owners, an agreement needs to be made with regard to the use of fertilizers.

Experimental investigation of performance properties and agglomeration behavior of fly ash from gasification of corncobs

The gasification industries make use of biomass residue as feedstock to produce synthesis gas,but the gasification of this waste biomass generates tons of ash everyday.Performance properties and agglomeration behavior of corncob ash(CCA) collected from the gasification of corncobs in a pilot-scale gasification station were investigated by using some experimental methods.Based on the chemical composition results,the agglomeration tendency of CCA from combustion and gasification process was also analyzed.Chemical analysis shows that the fly ash is mainly composed of inorganic matters formed by K,Mg,Ca,Na,Fe,Al,S,etc.The agglomeration characteristics indicate that the slagging degree increases with the increase of ashing temperature,and the slagging tendency of these CCA samples from gasification or combustion is different with various slagging indices.All CCA samples from combustion or gasification can cause slagging/fouling problems in thermal conversion systems.The applications of CCA are closely related to its performances,and CCA has the potential to be used in various fields,for example,as a material for ceramic products and activated carbon,as an adsorbent,as a crude fertilizer,and as a structural material.

Effect and mechanism of siderite on reverse anionic flotation of quartz from hematite

Reverse flotation technology is one of the most efficient ways to improve the quality and reduce impurity of iron concentrate. Mineral processors dealing with hematite face a challenge that the flotation results of reverse flotation of hematite are poor in presence of siderite using fatty acid as collector, starch as depressant of iron minerals and calcium ion as activator of quartz at strong alkaline pH. In this work, the effect of siderite on reverse anionic flotation of quartz from hematite was investigated. The effect mechanism of siderite on reverse flotation of hematite was studied by solution chemistry, ultraviolet spectrophotometry(UV) and Fourier transform infrared spectroscopy(FTIR). It was observed that siderite had strong depressive effect on quartz in flotation using sodium oleate as collector, corn starch as depressant of iron minerals and calcium chloride as activator of quartz at strong alkaline pH. The starch was adsorbed onto calcium carbonate by chemical reaction which was formed by CO^(2-)_3 from siderite dissolution and Ca^(2+) from calcium chloride as activator of quartz and precipitated on the surface of quartz, which resulted in improving the hydrophilic ability of quartz.