为了进一步提高种子含水率的高光谱估算精度,该研究测定了156份油用牡丹种子的近红外吸收光谱及其对应的含水率值,分析了近红外吸收光谱、一阶微分光谱、水分吸收特征参数与含水率的相关关系,构建了基于特征波长吸收光谱、特征波长一阶微分光谱、水分特征吸收参数和BP神经网络的油用牡丹种子含水率估算模型,并对模型进行了验证;再结合一元线性回归(SLR,Single Linear Regression)、逐步多元线性回归(SMLR,Stepwise MultipleLinear Regression)、偏最小二乘回归(PLSR,Partial Least Squares Regression)模型与BP神经网络(BPNN,BP Neural Network)模型进行比较.结果表明:1)油用牡丹种子含水率的吸收光谱特征波长位于1410、1900、1990 nm,一阶微分光谱特征波长位于1150、1950、2080 nm;2)以DF2080和AD2140为自变量建立的一元线性回归模型预测效果较优,在能够满足水分估算精度的情况下,是最优的选择方法.3)将优选的特征参数作为输入,实测含水率值作为输出,构建BP神经网络模型,其建模与验模R2分别为0.978和0.973,RMSE分别为0.220％和0.242％,而RPD值分别为6.478和5.889,与其他模型相比,BP神经网络模型的建模及预测精度均最高,是估算油用牡丹种子含水率的最优模型,其次为逐步多元线性回归模型.研究结果表明BP神经网络模型对种子含水率具有更好的预测能力,是估算油用牡丹种子含水率的有效方法.

随着人们为资源环境的重视,不可避免的对资源环境方面人才的需求也在不断加大,因此,教育部设置了资源环境科学专业.本研究针对我国目前开设资源环境科学专业的院校,分析了资源环境科学专业在我国本科院校中的开设规模、院校的区域、建设级别、所属主管单位级别、在院校中的所属二级学院特征以及招生批次等方面的特征;旨在反应目前我国资源环境科学专业的总体现状,为该专业的发展提供数据支撑.

Cleome gynandra and Cleome hassleriana , which are C 4 and C 3 plants, respectively, are two species of Cleome. The close genetic relationship between C. gynandra and C. hassleriana provides advantages for discovering the differences in leaf development and physiological processes between C 3 and C 4 plants. MicroRNAs (miRNAs) are a class of important regulators of various biological processes. In this study, we investigate the differences in the characteristics of miRNAs between C. gynandra and C. hassleriana using high-throughput sequencing technology. In total, 94 and 102 known miRNAs were identified in C. gynandra and C. hassleriana , respectively, of which 3 were specific for C. gynandra and 10 were specific for C. hassleriana . Ninety-one common miRNAs were identified in both species. In addition, 4 novel miRNAs were detected, including three in C. gynandra and three in C. hassleriana . Of these miRNAs, 67 were significantly differentially expressed between these two species and were involved in extensive biological processes, such as glycol-metabolism and photosynthesis. Our study not only provided resources for C. gynandra and C. hassleriana research but also provided useful clues for the understanding of the roles of miRNAs in the alterations of biological processes in leaf tissues during the evolution of the C 4 pathway.

Nanofertilizers may be more effective than regular fertilizers in improving plant nutrition, enhancing nutrition use efficiency, and protecting plants from environmental stress. A hydroponic pot experiment was conducted to study the role of foliar application with 2.5 mM nano-silicon in alleviating Cd stress in rice seedlings ( Oryza sativa L. cv Youyou 128) grown in solution added with or without 20 μM CdCl 2 . The results showed that Cd treatment decreased the growth and the contents of Mg, Fe, Zn, chlorophyll a, and glutathione (GSH), accompanied by a significant increase in Cd accumulation. However, foliar application with nano-Si improved the growth, Mg, Fe, and Zn nutrition, and the contents of chlorophyll a of the rice seedlings under Cd stress and decreased Cd accumulation and translocation of Cd from root to shoot. Cd treatment produced oxidative stress to rice seedlings indicated by a higher lipid peroxidation level (as malondialdehyde (MDA)) and higher activities of antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), and a lower GSH content. However, those nano-Si-treated plants had lower MDA but higher GSH content and different antioxidant enzyme activities, indicating a higher Cd tolerance in them. The results suggested that nano-Si application alleviated Cd toxicity in rice by decreasing Cd accumulation, Cd partitioning in shoot and MDA level and by increasing content of some mineral elements (Mg, Fe, and Zn) and antioxidant capacity.

Spectinomycin is an aminoglycoside antibiotic that inhibits prokaryotic-like protein synthesis by blocking translocation of messenger RNA and transfer RNAs on the ribosome. Mutants resistant to this antibiotic have been isolated from a wide range of bacteria, the alga Chlamydomonas and from chloroplasts of different species of higher plants. Usually a single nucleotide substitution occurred on chloroplast 16S ribosome RNA gene is sufficient to resist spectinomycin. Mutation rates of 16S rRNA gene of Nicotiana tabacum L treated with different concentrations of spectinomycin were studied. The results showed a sharp decrease of green resistant shoots from 30 to 300 mg l -1 spectinomycin, then an increase from 300 to 500 mg l -1 and finally a gradual decrease from 500 to 1000 mg l -1 . The increasing number of green resistant shoots from 300 to 500 mg l -1 spectinomycin indicates that the higher selective pressure applied by the antibiotic promoted a faster evolutionary rate of 16S rRNA gene. Furthermore, a new substitution site of 16S rDNA which conferred resistance to spectinomycin was isolated and confirmed by sequencing, endorsing that mutation is due to selection through high concentration of the antibiotic.

The low-molecular-weight glutenin subunits(LMW-GS) encoded at Glu-3 loci are important for the end-use quality of durum wheat.The present paper reported two novel LMW-GS genes(LMW-LDN1 and LMW-LDN2) isolated from durum wheat cultivar Langdon using PCR method.The full coding regions of LMW-LDN1(GenBank accession number:DQ659333) and LMW-LDN2(GenBank accession number:DQ659334) were composed of 1005 and 894 nucleotides,which were translated into proteins of 334 and 297 amino acids,respectively.They all had the typical structure of LMW-GS genes.The two genes were assigned to Glu-A3 locus through the analysis of LDN1D(1A) and LDN1D(1B) substitution lines.

Aimed to investigate the molecular mechanism of exogenous silicon to alleviate Cd toxicity in plants,the expression of rice γ-Glutamylcysteine Synthethase(γ-ECS) under Cd stress was studied by the semi-quantitative RT-PCR using EF-1α gene as a control.The results showed that γ-ECS gene was expressed in leaves and roots,and the transcribing of γ-ECS gene in rice was slightly enhanced by spraying Nanometer silicon on rice seedlings under Cd stress.The semi-quantitative RT-PCR was reliable,specific and easier to operate in research.

In order to select suitable plant varieties for absorption of heavy metal from city tail water,the study focused on heavy metals of Zn,Cu,Pb and Cd removal efficiency from city tail water by sorrel(Rumex acetosa L.),herb of glomerate galingale(Cyperus glomeratus L.) and swamp morningglory(Ipomiea aquatica Forsk).The removal efficiency of Cd and Pb was also studied by sorrel from artificial wastewater.The results showed that the removal efficiency of Zn,Cu,Cd,Pb were 74.33%,60.43%,45.45% and 36.43%,respectively,by three plants in this experiment.Among the three plants,sorrel had the best removal effect on these heavy metals,followed by herb of glomerate galingale and swamp morningglory.The removal efficiency of Zn,Cu,Cd,Pb by sorrel were 86.63%,90.37%,76.81% and 66.67% respectively;when the contents of Cd and Pb were in the range of 0.5-2.0 mg/L and 0.2-0.4 mg/L,respectively,the removal efficiency of Cd,Pb were about 67% and 55% respectively by sorrel.However,high concentration of these heavy metals was toxic to sorrel,resulting in the biomass decrease.As a result,sorrel was more suitable for removing heavy metals from city tail water and had a great tolerance at the low concentration of Cd and Pb.

In order to find a feasible phytoremediation to restore severe eutrophic water,two aquatic macrophytes Elodea nuttallii and Jussiaea stipulacea Ohwi were employed in floating artificial eutrophic water to get insight into differences involved in nutrient removal during incubation periods.The results illuminated that the removal percentages of total nitrogen(TN),ammonium(NH4-N),nitrate,phosphorus(TP),COD and Chlorophyll by Elodea nuttallii were 62.9%,90.83%,53.90%,71.21%,43.33% and 50.05%,respectively,Corresponding pecentages for Jussiaea stipulacea Ohwi were 93.56%,97.38%,99.44%,97.74%,52.49% and 58.34%,respectively.Analysis of variance revealed difference of removel effects between two aquatic macrophytes was significant(P<0.05).So Jussiaea stipulacea Ohwi is suited to restore severe eutrophic water because of its strong nutrient removal ability,while Elodea nuttallii can play great role in maintaining the water quality.

利用中国稻-麦轮作O3FACE(Free-air O3 concentration enrichment)试验平台,研究了连续3年大气O3浓度升高(较周围大气高50％)对稻田表层(O～20 cm)土壤团聚体、土壤容重及孔隙度和氮磷钾养分含量的影响.结果表明,大气O3浓度升高显著增加耕层土壤0.25 ～0.053 mm团聚体23.5％和降低＜0.053 mm团聚体24.6％.O3污染具有增大0～10 cm土层和降低10 ～ 20 cm土层土壤容重的趋势,0～10 cm土壤中气体孔隙度显著减小39.8％,10 ～ 20 cm土壤中毛管孔隙度显著增加9.1％和气体孔隙度显著减小32.4％,改变了固、液、气三相比.长期O3污染显著降低土壤全氮含量10.5％和速效钾13.3％,显著增加有效磷40.8％,但对有效氮未产生显著影响.结果表明,长期臭氧污染将改变土壤物理结构和养分物质的生物地球化学循环.

In order to clear removal efficient of nutrient pollutions from bio-ceramic filter equipment,low-cost ceramic as a filter was selected to treat city tail water.The equipment was operated under the condition: 2 h hydraulic retention time,and aeration Intensity at 0.4 L/min to treat tail water from sewage plant.The results showed that bio-ceramic filter had the highest removal efficiency to NH3-N,and the value achieved above 76%.At the same time,TN,TP and COD could be remove simutlaneously.The adsorption isotherms of NH3-N by spherical ceramic fit the Freundlich Model,it showed that the adsorption of NH3-N is Multi-layer adsorption.The ceramic’s adsorption on NH3-N is about to saturation after 5 h.These results can be used as a basis to explore suitable,ecomomic,and effective technical systems for city of tail water.

Esterase isozymes of different maize varieties were analyzed by polyacrylamide gel electrophoresis.The results showed rich expression and strong specificity in enzyme spectrums of all the varieties,and there were stable and consistent bands of basic enzymes in many alleles.There were 76 enzyme bands in total for experiment materials.The numbers were significantly different between varieties,10 for the largest and 5 for the least.Some varieties possessed similar enzyme sites,but there were specific enzyme bands in various types due to different degree of staining.In the relationships,Ganxinhuanuo No.1 and Taiwanchaotian No.38 were the farthest,Yuhe 988 and Yucaitiannuo No.1 were closer,and Luoyang 800,Shendan 16 and Ludan 981 were the nearest based on calculation of zymography combined coefficient.

Peroxide isozymes of 10 maize species were analysed by polyacrylamide electrophoresis.The results showed that there are a rich expression and strong specificity in painted enzyme.There is stability consistent with the basic enzyme in many alleles.It appears 36 enzyme for total experiment material.The number is significant in differences variety with the largest number 6 and the least 2.In the relationships,Luoyang 800,Shendan 16 and Taiwanchaotian No.38 are the farthest based on studying esterase isozymes.Huayu No 12 and Zhangyu No.9 are closer.Luoyang 800 and Shendan 16 are nearest.

The metallothionein gene ricMT in rice young roots was induced significantly under copper(Cu) or cadmium(Cd).The prokaryotic expression vector of ricMT was constructed and transformed into E.coli for tolerance analysis.After induced with IPTG,the growth of recombinants was more prosperous than that of controls under Cu,Cd or H2O2 stresses.The results suggested ricMT expression can improve E.coli tolerant to various heavy metal stresses.

A fast,simple and convenient method is established to isolate and characterize the cpDNA in leaves of Quercus variabilis.The protocol includes: chloplast isolation,deoxyribonuclease treatment,deproteinisation and purification of the DNA.The technique is inexpensive and appropriate for the isolation of cpDNA and is easy to obtain cpDNA with high purity and high quality.RAPD analysis system has also been established for study of this cpDNA.

In order to find a feasible biotechnology to remediate eutrophic water,an experiment of treating the artificial eutrophic water with immobilized photosynthetic bacteria was carried out.The results showed that the inoculation of immobilized photosynthetic bacteria could reduce the nutrients in water effectively.The removal rates of TN,NH4-N,NO3-N,TP,and COD were 65.94%,79.84%,78.80%,62.95%,and 78.06%,respectively,after 19 days of treatment.Furthermore,immobilized photosynthetic bacteria inhibited algae growth in the water.The inoculation of immobilized photosynthetic bacteria also increased DO,pH value,the rate of nitrification,and the number of photosynthetic bacteria,and the change of all these factors had an impact on nutrient removal efficiency in water.Therefore,the inoculation of immobilized photosynthetic bacteria could achieve the goal of nutrient removal in the eutrophic water remediation.

在高等农业院校的农业气象学教学中,应激发学生学习热情,提高其学习兴趣.本文从绪论教学、引用农谚、运用事例、使用多媒体手段以及加强实验教学等几个方面对其进行了探讨.

BAC subclone library is an important platform for sequencing the whole genome or some specific regions.In order to accelerate the process of sequencing the wheat genome,a BAC clone(BAC790010)from Langdon library was selected as material,and then was broken by DNA shearing instrument to produce many DNA fragments with different sizes,from which the 3-5 kb DNA fragments were retrieved and cloned to TOPO vector and then the subclone library was constructed that was suitable for shotgun sequencing.This BAC subclone library would provide a platform for gene cloning and genome research of wheat.

Genetics experiment is a compulsory course.In order to improve student's ability to practice and cultivate their creative thought,this study analyzes problems in the course of genetics experiment,puts forward methods of teaching reform in this experiment course,and sets up models for the training of innovation ability.

The basic principle of mRNA differential display PCR technology and its optimization,advantages and disadvantages were sum up.The achieved research results by using this method were summarized from the aspects of crop development and differentiation,hormone regulation,and the resistance.And its application prospect was analyzed.