Molecular Identification and Cultivar Fingerprints of Prunus persica （L.） Batsch Germplasms

[Objective] The aim was to study the molecular identification and cultivar fingerprints of Prunus persica （L.） Batsch germplasms.[Method] Sixty peach genotypes,representing China common local cultivars and European samples were screened by microsatellites （simple sequence repeats,SSRs） and Inter-Simple Sequence Repeat （ISSR） markers.[Result] 26 reproducible bands were amplified by Nine SSR primers,and 24 of which were polymorphic; 236 bands were amplified by 30 ISSR primers,and 113 of which were polymorphic.31 genotypes were discriminated with 1-3 distinct polymorphic bands generated from the primers ISSR and SSR.Seven cultivar-specific ISSR fragments and two SSR unique alleles obtained from this study were available to be converted into Sequence Characterized Amplified Region （SCAR） markers.The genetic similarity coefficient （GS） estimated from these molecular data averaged were 0.939 （ranged from 0.856 to 0.983） for ISSR and 0.646 （ranged from 0.240 to 1.000） for SSR,respectively.The combined grouping association indicated that most local Chinese peach cultivars and exotic accessions were clustered together.This could be related to the mode of introduction and maintenance of the peach cultivars involving limited foundation germplasm,exchange of cultivars between plantations,and periodic development of new recombinant cultivars following sexual reproduction.[Conclusion] The results obtained in this work would help to improve the conservation,molecular identification and management of peach germplasm in breeding.     

Construction and Characterization of a cDNA Library from the Pulp of Coconut （Cocos nucifera L.）

To investigate the gene expression profile of endosperm development, a cDNA library was constructed and characterized from the pulp of coconut at different developmental stages. The constructed cDNA library incorporated approximately 1 × 10^7 clones in total, and the size of the insertion fragments ranged from 800 to 2 000 bp. Sequencing results of 100 randomly picked clones showed that the recombination rate was 96%. In subsequent sequence analysis, 41 clones （41%） were homologous to known function proteins, and 23 clones showed high amino acid identity （more than 80%） with the corresponding genes of different plants. Semi-quantitative RT-PCR indicated that oleosin and globulin genes are pulpspecific expression, and have differential expression level in different developmental stage. Clone 29, recognized as homologous to KIAA1239 protein （Homo sapiens）, was observed to occur nine times, indicating that this gene may be over-expressed during the endosperm development stage. However, the homologous protein was found only in mammals, and the detailed function is still unknown. Elucidation of the functional characterization of these genes will be carried out immediately.     

Identification of Organic Substances Associated with Tissue Senescence in Upland Cotton （Gossypium spp. L.） Based on GC-MS Analysis

Premature senescence in crop production,especially occurred at the late growth stage,generally results in a reduction in yield and quality.Therefore,it is beneficial for yield and quality to properly delay senescence of plant tissues during the late developmental stage.In this study,it was observed that the chlorophyll content and photosynthetic rate were gradually decreased along leaf growth progression,and the rates of reduction were promoted by drought.Based on gas chromatography-mass spectrometry (GC-MS) analysis,total eight,five,seven,and five kinds of organic compounds that putatively associated with the tissue senescent progression were identified in leaves,fruit branches,petals,and sepals,respectively.It was found that the identified organic compound,such as α-pinene,β-pinene,and pentadecane were present in different tissues.Among the total ten organic substances identified to be related with the leaf senescence,half were specifically detected in the drought treatment.These results suggest some biochemical pathways associated with the leaf senescence are distinctly regulated by drought.The identified organic compounds in the tested tissues showed three types on the performance pattern based on the contents along with the senescent progression,including gradually increasing,decreasing,and a curve with one single peak.Thus,during the senescence process in tissues,a subset of metabolic substances occur modifications on the quantities,reflecting a complicate biochemical reactions are initiated via the senescence signals.Further analysis of the important organic substances will be helpful for elucidation of the tissue senescence mechanism at the biochemical level and provide a new insight of the senescence signaling transductions in cotton.     

Isolation and Expression Analysis of Two Genes Encoding Cinnamate 4-Hydroxylase from Cotton （Gossypium hirsutum）

Two genes （GhC4H1 and GhC4H2） that encode putative cotton cinnamate 4-hydroxylases that catalyze the second step in the phenylpropanoid pathway were isolated from developing cotton fibers. GhC4H1 and GhC4H2 each contain open reading frames of 1 518 base pairs （bp） in length and both encode proteins consisting of 505 amino acid residues. They are 90.89% identical to each other at the amino acid sequence level and belong to class I of plant C4Hs. GhC4H1 and GhC4H2 genomic DNA are 2 247 and 2 161 bp long, respectively, and contain two introns located at conserved positions relative to the coding sequence. GhC4HI and GhC4H2 promoters were isolated and found to contain many cis-elements （boxes P, L and AC-1 element） previously identified in the promoters of other phenylpropanoid pathway genes. Histochemical staining showed GUS expression driven by the GhC4H1 and GhC4H2 promoters in ovules and fibers tissues. GhC4H1 and GhC4H2 were also widely expressed in other cotton tissues. GhC4H2 expression reached its highest level during the elongation stage of fiber development, whereas GhC4H1 expression increased during the secondary wall development period in cotton fibers. Our results contribute to a better understanding of the biochemical role of GhC4H1 and GhC4H2 in cotton fiber development.     

Molecular Identification and Expression Analysis of GhHYDRA 1 Gene,a Homologue of HYDRA1 Gene From Upland Cotton （Gossypium hirsutum L.）

Beside as precursors of BRs biosynthesis,more and more evidences supposed that phytosterols play an important role in plant growth and development.To investigate the effects of phytosterols on the fiber development of upland cotton(Gossypium hirsutum L.)and the molecular base of sterol regulating cotton fiber growth,a homologue of HYDRA1 was cloned from upland cotton(cv.Xuzhou 142)by screening cotton fiber EST database and contigging the candidate ESTs.The GhHYDRA1 encoded a polypeptide of 218 amino acid residues and the deduced amino acid sequences had high homology with the members of HYDRA1 in Populus trichocarpa,Solanum tuberosum,and Arabidopsis thaliana.Moreover,GhHYDRA1 had comparable transmembrane regions to AtHYDRA1 in sequence,length,order,and spacing,except for a C-terminal polylysine cluster.Quantitative real-time RT-PCR analysis revealed that the higher expression levels of GhHYDRA1 gene were detected in 6 to 12 DPA(days post anthesis)fibers,while the lower levels were observed in 0 DPA ovule(with fibers)and 16 to 18 DPA fibers.These results indicated that GhHYDRA1 is the homologue of HYDRA1 gene and plays a crucial role in fiber elongation.Furthermore,auxin and BL up-regulated the expression level of GhHYDRA1 while ABA and KT down-regulated the expression level of GhHYDRA1 in cotton ovule and fiber growth.The result suggested that phytosterols play a role in the interaction of plant hormones.     

Resistance to the Whitefly Aleurotrachelus socialis（Hemiptera：Aleyrodidae） and SSR Marker Identification in Advanced Populations of the Hybrid Manihot esculenta subsp.Manihot flabellifolia

Genes resistant to Aleurotrachelus socialis were transferred to the F 1 from the interspecific hybrid wild species of Manihot flabellifolia to M.esculenta and two advanced generations of backcrosses（BC 1 and BC 2）.We characterized the resistance of A.socialis transferred to BC 2 parents（CW67-160,CW67-130,CW67-44）,MTAI-8（BC 1）,resistant（CMB9B-73） and susceptible（CMB9B-104） genotypes from contrasting pools,and resistant（MEcu-72） and susceptible（CMC-40） genotypes.Whitefly demography and biology were evaluated.SSR molecular markers associated with a phenotypic response of plant resistance were detected in segregating populations（BC 2）.Results showed that although female survival time was similar on all hosts,the lowest averages of longevity,fecundity and oviposition rate were observed in the resistant control MEcu- 72,only being significantly similar to the parent CW67-130.When the BC 1 and BC 2 populations were compared,it was found that A.socialis fecundity was eight times lower on CMB9B-73 progeny than on CW67-130,expressing the highest levels of resistance to the whitefly.Ten genotypes of CMB9A and CMB9B family had the best segregation.A total of 486 microsatellite primers were evaluated using bulked segregant analysis（BSA）,11 showed polymorphism between the contrasting pools and only one showed significant differences between resistant and susceptible individuals.In conclusion,fecundity was the parameter that impacted most on the intrinsic rate of A.socialis population growth.     

黄顶菊种子萌发特性研究

从光照、温度、土壤含水量和空气相对湿度等方面,研究了其对黄顶菊种子萌发的影响。结果表明：光照促进黄顶菊种子萌发;适于黄顶菊种子萌发的温度为25～40℃;土壤含水量在30％～90％时,有利于黄顶菊种子萌发;空气相对湿度对黄顶菊种子萌发影响较小。     

外来入侵植物黄顶菊的化感作用初步研究

为明确黄顶菊对其他植物的化感作用,利用黄顶菊茎叶的不同提取物对几种植物的生长影响进行了测定。结果表明,黄顶菊茎叶水提物对玉米、小麦、棉花、大豆、花生、马唐和反枝苋都表现出了不同程度的抑制作用,其中以对棉花的化感效应最强,在其浓度为0.2 g/mL时,对根长和茎长的化感指数分别为-0.85和-0.88,而该水提物对水稻的生长则表现为促进作用。黄顶菊茎叶的石油醚、氯仿、乙酸乙酯、丙酮和乙醇的提取物,对几种植物的化感效应要高于水提物,其中以丙酮提取物的化感效应最强。利用重结晶法从黄顶菊茎叶的丙酮提取物中得到了一个具有除草活性的物质,该物质的熔点为192.5℃~193.5℃,最大吸收波长为220 nm,初步判断该化合物是一种碱性有机物,该物质在浓度为1000,500,100,50 mg/L时,对马唐,反枝苋生长均有抑制作用。     

The Extraction,Isolation and Identification of Exudates from the Roots of Flaveria bidentis

Large amounts ofFlaveria bidentis＇s root culturing solution were obtained by using DFT （deep flow technique） equipment and these solution which was vacuum concentrated （10, 20 mg mL-~） can have a certain inhibition on Triticum aestivum, Cucumis sativus, Raphanus sativus, Amaranthus retroflexus, Setaria viridis, Chenopodium album, Echinochloa crusgalli and Chloris virgata. This outcome suggested some active compounds in the root exudates ofFIaveria bidentis can inhibit the germination, seedling elongation and root length. The dichloromethane extract of root exudates was identificated by GC-MS, and 29 kinds of compounds, including esters, hydrocarbons, ketones, thiazole, amines, etc. were obtained and the phthalate n-octyl ester, phthalate 2-ethylhexyl ester were proved to be allelochemicals. The culturing solution of root exudates was separated through the resin column and silica gel column and a component inhibiting seedling height, root length and fresh weight of wheat was got. There were 6 kinds of organic compounds in this component including dioctyl phthalate, 1,2-phthalate, mono（2-ethylhexyl） ester by GC-MS.     

危险性外来入侵植物—黄顶菊在山东省的发生与分布

为掌握黄顶菊在山东省的分布和发生情况,实地调查了毗邻黄顶菊初发地河北省的山东省西北部。结果表明,与河北省毗邻的聊城、德州、济南均见黄顶菊疫情,其中聊城灾情最重,在夏津已发现黄顶菊侵入农田。调查还发现,黄顶菊主要沿城市与城市,城市与乡镇之间的主要干道传播,且动物和交通工具都是其传播媒介。黄顶菊在山东的分布调查,为山东黄顶菊的防治奠定了基础。     

The allelopathy of Flaveria bidentis (L.) Kuntze, an invasive weed species

To identify the allelopathic effect of Flaveria bidentis (L.) Kuntze (F. bidenti) on other plants, the effects of different extracts from F. bidentis on the growth of several plants were studied by bioassay. Results showed that the water extracts inhibited the growth of corn (Zea mays L.), wheat (Triticum aestivum L.), cotton (Gassypium Hirsutum L.), soybean (Glycine hispida L.), peanut (Arachi shypogaea L.), rice (Oryza sativa L.), crabgrass (Digitaria sanguinalis L.) and rigweed (Amaranthus retroflexus L.), with the most reactive indexes found in root and stem of cotton at −0.85 and −0.88, respectively, at a concentration of 0.2 g·mL⁻¹. However, the water extracts accelerated the growth of rice. In addition, the reactive indexes of the extracts of petroleum ether chloroform, ethyl acetate, acet and alcohol were higher than that of the water extracts, and that of the acet extracts was the highest. The melting point of the refined acetone extract ranged from 192.5°C to 193.5°C, and its maximum absorbing wavelength was 220 nm. This extract was found to be herbicide-active and played an inhibitory role in the growth of crabgrass and rigweed at concentrations of 1000, 500, 100 and 50 mg·L⁻¹. __________ Translated from Journal of Agricultural University of Hebei, 2007, 30(6): 63–67 [译自 : 河北农业大学学报]     

黄顶菊对几种作物生长影响的作用机理初步研究

在室内土壤盆栽条件下,探讨了黄顶菊对附近生长的萝卜、玉米、黄瓜和小麦植株生长的影响,结果发现,黄顶菊对供试4种作物种子的萌发以及株高和鲜重增长都有明显的抑制作用,其中对黄瓜、萝卜的抑制作用更强。研究还发现,生长在黄顶菊附近的萝卜、玉米、黄瓜和小麦根系活力明显低于对照,叶片的可溶性蛋白、叶绿素含量以及SOD、POD、CAT活力均低于对照,而丙二醛含量高于对照。结果预示黄顶菊可能通过根系分泌物对附近的作物施加影响。     

瓜果腐霉除草活性成分的分离鉴定

 【目的】为了明确瓜果腐霉在液体培养基中所产生粗毒素的具有除草活性成分的组成及结构,本研究对具有除草活性毒素成分进行了分离纯化和结构鉴定。【方法】瓜果腐霉培养滤液分别用乙酸乙酯、石油醚、三氯甲烷等不同极性溶剂萃取制备粗毒素,用薄层层析法对粗毒素进行分离,再用高效液相色谱分离制备得到除草活性成分,通过核磁共振谱和红外光谱对其进行结构解析。【结果】用乙酸乙酯萃取得到的粗毒素活性最高;以Rf值为0.19的物质除草活性最强,对马唐的生长抑制作用达到5级;通过化学信息分析表明该成分为邻苯二甲酸二甲酯。【结论】邻苯二甲酸二甲酯是瓜果腐霉在液体培养过程中所产生的组分之一,具有除草活性。     

Isolation and Structural Indentification of Herbicidal Toxin Fractions Produced by Pythium aphanidermatum

In order to understand the compsition and structure of herbicidal component of Pythium aphanidermatum,the isolation and structural indentification were researched.The culture filtrate was extracted by ethyl acetate,petroleum,and chloroform with the same volume respectively and the activity of the crude toxin was bioassayed.The toxin was separated by using the method of thin layer chromatography（TLC）,then the main fraction was separated by HPLC,and the structure was analyzed by the sepctrum of IR,13C-NMR and 1HNMR.The results showed that the ethyl acetate extracts had the strongest herbicidal activity.Using the method of TLC,the bioassay results showed that the extracts with Rf 0.19 had the strongest effect on weeds and the inhibition to Digitaria sanguinalis and Amaranthus retroflexus reached five levels,and the component was proved to be dimethyl o-phthalate from the spectrum of IR,13C-NMR and 1HNMR,which was one of the components from the toxin,and it had herbicidal activity.     

基于MaxEnt模型和气候变化情景入侵种黄顶菊在中国的分布区预测

为了分析入侵种黄顶菊[Flaveria bidentis (L.) Kuntze.]在中国的潜在适生分布区,利用最大熵模型(MaxEnt)与ArcGIS软件预测了黄顶菊在当前及未来气候条件下在中国的潜在适生分布区。结果表明：在当前气候条件下,黄顶菊主要分布在河北省大部分地区、北京市南部、河南省北部以及天津市的西部地区;未来气候条件下,黄顶菊的适生分布范围将进一步扩大,在2060年前后,高适生区的面积将增长到14.73万km ²,增长率达121.49%,主要分布在河北省及周边地区、陕西省西安市及周边城市。运用刀切法(Jackknife)计算各个环境变量对物种分布的影响,最冷月最低温度、最冷季平均温度、年平均气温、最干季平均温度、海拔、温度季节性变化标准差、最湿季度平均温度和最暖季平均温度8个环境变量是影响黄顶菊分布的主要因素。模型的AUC值为0.987,表明模型的准确度非常高。未来气候变化情景下黄顶菊的分布范围将进一步扩大,建议相关部门对此密切关注,并尽早采取防护措施。     

不同产地土壤因子与黄顶菊黄酮类成分相关性分析

分析黄顶菊黄酮类成分与土壤因子的相关性,为黄顶菊的综合利用与防治提供理论依据。以河北省献县的3个村庄附近黄顶菊样地为研究对象,测定样地土壤养分质量分数及黄顶菊黄酮类成分,利用SPSS19.0软件对数据进行多重比较和相关分析。结果显示,速效磷、碱性磷酸酶对黄顶菊地上部分黄酮类成分的积累显著相关;环境的微小变化会影响黄顶菊黄酮类成分的累积。