陆地棉耐盐性状与SSR分子标记的关联分析

本研究以134份陆地棉栽培种为试验材料,测定其在0.3%盐浓度(质量分数)下的出苗率,并使用74对SSR引物对这些材料进行基因组变异扫描。利用Structure2.3.4软件分析该自然群体的遗传结构,在此基础上采用Tassel2.1软件对耐盐性状与SSR分子标记进行关联分析,寻找与棉花耐盐性状相关的分子标记。研究结果表明:(1)134份陆地棉栽培种的出苗率呈极显著差异,并筛选出27个盐敏感材料和10个耐盐材料。(2)74个SSR分子标记共检测出148个多态性位点,涉及246个等位变异,变异范围为2~7,平均每个标记3.32个;基因多样性指数变异范围为0.0295~0.4959,平均值为0.2897;SSR分子标记多态性信息含量(PIC)变幅为0.0290~0.3729,平均值为0.2381。(3)通过群体结构分析,将该自然群体划分2个亚群体,分别包含89份和45份材料。(4)关联分析共发现8个与棉花耐盐性状相关的SSR分子标记位点,表型变异解释率变幅为2.91%~7.82%,平均值为4.32%。此研究结果可以为棉花耐盐性状分子标记辅助选择育种提供参考。     

立体绿化集成技术配套产品开发利用研究进展

当前立体绿化在国内多个大中城市中得到了蓬勃发展,促进了相关配套产品的研发和推广应用,同时新型的配套产品又推动了立体绿化的快速发展。本文对华南地区立体绿化基质产品、蓄水种植容器、植被毯、绿墙、生态植被砖等相关配套产品的研发及应用情况展开综述,旨在为今后能更有效地推广立体绿化集成技术及相关产品提供参考。     

Study on dynamics of stem form of Korean pine trees in natural forest stand

INTRODUCTIONThcstcmfonl1ofnaturalKorcanpincforcst.ot\ingtothcsupprcsscdandshadcd,isvcry'difTcrcntt`iththatofplantation.Itis\'cry't'aluabIctostud}'thcstcmfonnforn1orcac-knot`lcdgcabouttl1ctrccd)-nan1icsofnaturalKorcanpinc.n1crcl1asbccnconsidcrabIcrescarchontl1cstc111for111cquationsasatoolforforcstmanagcmcnt,butitalmostbasnorclationshipt`-iththcbiologicalgrowthproccss.soitisx'ery'dimcuIttouscthccquationtoanalxrsisthcd\'amicsofstclllform.Hcrcthcdct'clopmcntofstcmformt"ascxPCctcdfornotonI\…     

Analysis of strigolactones,germination stimulants for striga and orobanche,by high-performance liquid chromatography/tandem mass spectrometry

A simple and rapid analytical method for strigolactones, germination stimulants for the root parasitic weeds witchweed (Striga spp.) and broomrape (Orobanche spp.), has been developed using high-performance liquid chromatography connected to tandem mass spectrometry (LC/MS/MS). The natural strigolactones (strigol, sorgolactone, orobanchol, and alectrol) were clearly separated and identified by LC/MS/MS. As low as 0.1 pg/microL of strigol and 0.5 pg/microL of sorgolactone could be quantified, whereas 1 pg/microL was needed for the quantification of orobanchol (S/N > 10). Using this method, it was found that red clover produces orobanchol and alectrol but not strigol. The roots of red clover seedlings were found to produce 13, 70, 58, and 65 pg of orobanchol/plant 1, 2, 3, and 4 weeks after germination, respectively.     

Synthesis and Inhibitory Activities against Colon Cancer Cell Growth and Proteasome of Alkylresorcinols

We have identified alkylresorcinols (ARs) as the major active components in wheat bran against human colon cancer cell growth (HCT-116 and HT-29) using a bioassay-guided approach. To further study the structure-activity relationships, 15 ARs and their intermediates (1-15) were synthesized expediently by the modified Wittig reaction in aqueous media, and six 5-alkylpyrogallols and their analogues (16-21) were prepared by the general Grignard reaction. The synthetic AR analogues were evaluated for activities against the growth of human colon cancer cells HCT-116 and HT-29 and the chymotrypsin-like activity of the human 20S proteasome. Our results found that (1) AR C13:0 and C15:0 (13 and 14) had the greatest inhibitory effects in human colon cancer cells HCT-116 and HT-29, while decreasing or increasing the side chain lengths diminished the activities; (2) two free meta-hydroxyl groups at C-1 and C-3 on the aromatic ring of the AR analogues greatly contributed to their antitumor activity; (3) the introduction of a third hydroxyl group at C-2 (20 and 21) into the aromatic ring of the AR analogues yielded no significant enhancement in activity against HCT-116 cells and decimated the effects against HT-29 cells, but dramatically increased the activity against the chymotrypsin-like activity of the human 20S proteasome; and (4) AR C11:0 (12) was found to have the greatest effect in a series of AR C9:0-C17:0 against the chymotrypsin-like activity of the human 20S proteasome.     

油菜抗裂角性鉴定方法的改进及试验

为改进油菜抗裂角性鉴定技术,通过设计烘烤与不烘烤、烘烤后立即鉴定与密封保存隔夜后鉴定、不同摇床、震荡时间及钢珠数的单因素比较试验,分析了随机碰撞法鉴定油菜抗裂角指数的影响因素。结果表明,角果经80℃烘烤30 min并于室温封闭保存过夜后再鉴定,每震荡2 min记录一次裂角数,采用8个钢珠代替10个钢珠在HQ45Z恒温摇床上随机碰撞共10 min进行鉴定,可以显著提高鉴定结果的准确性和鉴定效率。通过比较改进前后随机碰撞法的鉴定结果,发现46份鉴定材料利用2种方法鉴定结果的相关系数为0.8844,相关性极为显著（P=3.705×10-16）。利用改进后方法鉴定的46份品种（系）,其抗裂角指数变异幅度为0～0.820,明显大于利用改进前方法鉴定结果的变异幅度（0.032～0.767）;且改进后方法鉴定结果的平均标准误差（0.0274）也明显小于改进前方法鉴定结果的平均标准误差（0.0348）,说明改进后方法提高了油菜抗裂角性鉴定的分辨率和准确性。研究为油菜抗裂角品种的选育和遗传研究提供技术依据。     

Different response of silicate fertilizer having electron acceptors on methane emission in rice paddy soil under green manuring

Cultivation of green manure plants during the fallow season in rice paddy soil has been strongly recommended to improve soil properties. However, green manuring may impact greenhouse gas emission, methane (hereafter, CH₄) in particular, under the flooded rice cultivation and thus, application of chemical amendments being electron acceptors can be an effective mitigation strategy to reduce CH₄ emissions in irrigated rice (Oryza sativa L.) field amended with green manure. To investigate the effect of iron (Fe) slag silicate fertilizer (hereafter, silicate fertilizer), which was effective in reducing CH₄ emission and increasing rice productivity, in green manure-amended paddy soil, the aboveground biomass of Chinese milk vetch (hereafter, vetch) was added at rates of 0, 10, 20, and 40 Mg (fresh weight) ha⁻¹ before the application of silicate fertilizer, which was added at rates of 0 and 2.3 Mg ha⁻¹. Silicate fertilization reduced the seasonal CH₄ flux by ca. 14.5% and increased rice yield by ca. 15.7% in the control (no vetch application) treatment. However, CH₄ production was increased by silicate fertilization in vetch-treated soil particularly at the initial rice growing stage, which was probably due to the enhanced decomposition of added organic matters by the silicate liming effect. In conclusion, silicate fertilization is not effective in reducing CH₄ production in green manure-amended rice paddy soils and its use should be properly controlled.     

Analysis of methanogenic archaeal communities of rumen fluid and rumen particles from Korean black goats

Molecular diversity of methanogens in the rumen of Korean black goats was investigated with 16S rRNA gene clone libraries using methanogen‐specific primers. The libraries were composed of rumen fluid‐associated methanogens (FAM) and rumen particle‐associated methanogens (PAM) from rumen‐fistulated Korean black goats. Among the 141 clones of the FAM library, the sequences were mostly related to two phyla, the Methanobacteriaceae family (77.3%) and the Thermoplasmatales family (22.7%); and among the 68 clones of the PAM library, sequences were also mainly clustered in the two phyla, the Thermoplasmatales family (63.24%) and the Methanobacteriaceae family (35.29%). Most of the sequenced clones in the two libraries were closely related to uncultured methanogenic archaeon. Quantitative real‐time PCR revealed that PAM (8.97 log 10) had significantly higher (P < 0.01) density of methanogens by the methanogenic 16S rRNA gene copies than FAM (7.57 log 10). The two clone libraries also showed difference in Shannon index (FAM library 1.70 and PAM library 1.59) and Chao 1 estimator (FAM library 18 and PAM library 17 operational taxonomic units). Apparent differences found in the microbial community from the two 16S rRNA gene libraries could be a result of such factors as the chemical and physical nature of the target material surface, types or component of diets, the interaction between the methanogens and other microbes, and age of the experimental goats.     

Biochar-induced changes in soil properties affected immobilization/mobilization of metals/metalloids in contaminated soils

Purpose

Remediation of metal contaminated soil with biochar is attracting extensive interest in recent years. Understanding the significance of variable biochar properties and soil types helps elucidating the meticulous roles of biochar in immobilizing/mobilizing metals/metalloids in contaminated soils.

Materials and methods

Six biochars were produced from widely available agricultural wastes (i.e., soybean stover, peanut shells and pine needles) at two pyrolysis temperatures of 300 and 700 °C, respectively. The Pb-, Cu-, and Sb-contaminated shooting range soils and Pb-, Zn-, and As-contaminated agricultural soils were amended with the produced biochars. The mobility of metals/metalloids was assessed by the standard batch leaching test, principal component analysis and speciation modeling.

Results and discussion

The changes in soil properties were correlated to feedstock types and pyrolysis temperatures of biochars based on the principal component analysis. Biochars produced at 300 °C were more efficient in decreasing Pb and Cu mobility (>93 %) in alkaline shooting range soil via surface complexation with carboxyl groups and Fe-/Al-minerals of biochars as well as metal-phosphates precipitation. By contrast, biochars produced at 700 °C outperformed their counterparts in decreasing Pb and Zn mobility (100 %) in acidic agricultural soil by metal-hydroxides precipitation due to biochar-induced pH increase. However, Sb and As mobility in both soils was unfavorably increased by biochar amendment, possibly due to the enhanced electrostatic repulsion and competition with phosphate.

Conclusions

It is noteworthy that the application of biochars is not equally effective in immobilizing metals or mobilizing metalloids in different soils. We should apply biochar to multi-metal contaminated soil with great caution and tailor biochar production for achieving desired outcome and avoiding adverse impact on soil ecosystem.

     

Antioxidant and antimelanogenic activities of polyamine conjugates from corn bran and related hydroxycinnamic acids

The antioxidant activity of three major polyamine conjugates, N,N'-dicoumaroyl-putrescine (DCP), N-p-coumaroyl-N'-feruloylputrescine (CFP), and N,N'-diferuloyl-putrescine (DFP) isolated from corn bran, and their related hydroxycinnamic acids, p-coumaric acid and ferulic acid, were evaluated by three antioxidant in vitro assay systems, including 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and superoxide and hydroxyl radicals generated by enzymatic and nonenzymatic reactions. Additionally, five phenolic compounds were evaluated for melanogenesis inhibitory activity using mushroom tyrosinase and B16 melanoma cells. Most of the phenolic compounds significantly scavenged DPPH, superoxide, and hydroxyl radicals in a dose-dependent manner. Particularly, DFP showed potent DPPH (IC50 = 38.46 microM) and superoxide (IC50 = 291.62 microM) radical scavenging activities, while DCP exhibited the strongest hydroxyl radical scavenging activity (IC50 = 120.55 microM). CFP also exerted moderate DPPH, superoxide, and hydroxyl radical scavenging activities. Meanwhile, DCP (IC50 = 181.73 microM) showed potent tyrosinase inhibitory activity toward l-tyrosine as the substrate, whereas DFP (IC50 = 733.64 microM) significantly inhibited melanin synthesis in B16 melanoma cells. These current results indicate that these three polyamine conjugates from corn bran may be useful potential sources of natural antioxidants and skin-whitening agents.