法兰地草莓的芳香类和黄酮类成分

为了解草莓(Fragaria×ananassa Duch.)法兰地品种的化学成分,采用色谱分离方法,从新鲜果实的乙醇提取物中获得19个化合物。通过波谱数据分析鉴定了它们的结构,分别为对羟基苯甲酸(1)、没食子酸乙酯(2)、鞣花酸3-O-α-L-鼠李糖苷(3)、苄基β-D-葡萄糖苷(4)、淫羊藿次苷F2(5)、苄基6-O-α-L-呋喃阿拉伯糖基-β-D-葡萄糖苷(6)、苯乙基6-O-α-L-呋喃阿拉伯糖基-β-D-葡萄糖苷(7)、反式肉桂酰基β-D-葡萄糖苷(8)、顺式肉桂酰基β-D-葡萄糖苷(9)、反式对香豆酰基β-D-葡萄糖苷(10)、顺式对香豆酰基β-D-葡萄糖苷(11)、反式阿魏酰基β-D-葡萄糖苷(12)、山柰酚(13)、反式椴树苷(14)、山柰酚3-O-β-D-葡萄糖醛酸苷(15)、槲皮素(16)、槲皮素3-O-β-D-葡萄糖苷(17)、槲皮素3-O-β-D-葡萄糖醛酸苷(18)和根皮苷(19),化合物1~12为芳香类,其余为黄酮类。所有化合物均为首次从法兰地品种中报道,化合物4~9为首次从草莓中获得。     

Assessing the impact of natural service bulls and genotype by environment interactions on genetic gain and inbreeding in organic dairy cattle genomic breeding programs

The objective of the present study was to compare genetic gain and inbreeding coefficients of dairy cattle in organic breeding program designs by applying stochastic simulations. Evaluated breeding strategies were: (i) selecting bulls from conventional breeding programs, and taking into account genotype by environment (G×E) interactions, (ii) selecting genotyped bulls within the organic environment for artificial insemination (AI) programs and (iii) selecting genotyped natural service bulls within organic herds. The simulated conventional population comprised 148 800 cows from 2976 herds with an average herd size of 50 cows per herd, and 1200 cows were assigned to 60 organic herds. In a young bull program, selection criteria of young bulls in both production systems (conventional and organic) were either ‘conventional’ estimated breeding values (EBV) or genomic estimated breeding values (GEBV) for two traits with low (h²=0.05) and moderate heritability (h²=0.30). GEBV were calculated for different accuracies (r_mg), and G×E interactions were considered by modifying originally simulated true breeding values in the range from r_g=0.5 to 1.0. For both traits (h²=0.05 and 0.30) and r_mg⩾0.8, genomic selection of bulls directly in the organic population and using selected bulls via AI revealed higher genetic gain than selecting young bulls in the larger conventional population based on EBV; also without the existence of G×E interactions. Only for pronounced G×E interactions (r_g=0.5), and for highly accurate GEBV for natural service bulls (r_mg>0.9), results suggests the use of genotyped organic natural service bulls instead of implementing an AI program. Inbreeding coefficients of selected bulls and their offspring were generally lower when basing selection decisions for young bulls on GEBV compared with selection strategies based on pedigree indices.     

The Protein Kinase CK2 Holoenzyme Structure Supports Proposed Models of Autoregulation and Trans-Autophosphorylation

Eukaryotic protein kinases are typically strictly controlled by second messenger binding, protein/protein interactions, dephosphorylations or similar processes. None of these regulatory mechanisms is known to work for protein kinase CK2 (former name “casein kinase 2”), an acidophilic and constitutively active eukaryotic protein kinase. CK2 predominantly exists as a heterotetrameric holoenzyme composed of two catalytic subunits (CK2α) complexed to a dimer of non-catalytic subunits (CK2β). One model of CK2 regulation was proposed several times independently by theoretical docking of the first CK2 holoenzyme structure. According to this model, the CK2 holoenzyme forms autoinhibitory aggregates correlated with trans-autophosphorylation and driven by the down-regulatory affinity between an acidic loop of CK2β and the positively charged substrate binding region of CK2α from a neighboring CK2 heterotetramer. Circular trimeric aggregates in which one-half of the CK2α chains show the predicted inhibitory proximity between those regions were detected within the crystal packing of the human CK2 holoenzyme. Here, we present further in vitro support of the “regulation-by-aggregation” model by an alternative crystal form in which CK2 tetramers are arranged as approximately linear aggregates coinciding essentially with the early predictions. In this assembly, the substrate binding region of every CK2α chain is blocked by a CK2β acidic loop from a neighboring tetramer. We found these crystals with CK2^Andante that contains a CK2β variant mutated in a CK2α-contact helix and described to be responsible for a prolonged circadian rhythm in Drosophila. The increased propensity of CK2^Andante to form aggregates with completely blocked active sites may contribute to this phenotype.     

Induction of tetraploidy in Buddleia globosa

The aim was to produce a tetraploid form of Buddleia globosa to facilitate introgression of yellow flower colour into B. davidii, which is naturally tetraploid. Protocols were established for the micropropagation of B. globosa and tetraploid plants were obtained by application in vitro of colchicine to pre-cultured excised nodal sections. Three concentrations of colchicine were applied (0.01%, 0.05% and 0.1% w/v) for 1, 2 or 3 days. At 0.01% tetraploids were produced only after 2 days of application. All other treatments produced at least one tetraploid. The colchicine technique was extremely effective: of 29 lines tested, 19 were tetraploid and 5 were mixoploid. The vegetative characteristics of these tetraploids are described and the flowering characteristics of the three that flowered. This revised version was published online in August 2006 with corrections to the Cover Date.     

干旱荒漠区银白杨树干液流动态

应用热扩散式树干茎流计(TDP)于2012年7月1日至7月25日,在克拉玛依地区农业开发区对银白杨(Populus alba L.×P.talassica)人工林树干液流速率进行了连续测定,并对气象、土壤水分等指标进行了同步测定。结果表明:7月份的晴天银白杨树干液流速率日变化呈单峰型,阴天呈多峰型,在测量时期液流速率日平均值为0.6059 L/h;银白杨树干单位边材面积的液流速率与太阳总辐射、大气温度、水汽压差呈极显著正相关关系,与相对湿度呈负相关关系。其相关系数绝对值顺序为太阳总辐射>大气温度>水汽压差>相对湿度>风速;银白杨边材面积与胸径之间存在着显著的线性相关关系,相关系数为0.834,单位边材面积的液流速率随树干胸径的增大而减小。     

植物激素对草莓叶片不定芽形成的影响

用试管内生长的草莓幼嫩叶片作外植体,培养在MS基本培养基上附加1.5—2.5毫克/升6—BA和0.1毫克/升NAA,可直接诱导成不定芽,诱导率可达20%。如果不定芽继代培养在同样浓度的培养基上,继而可形成大量的丛生芽。能使叶外植体形成不定芽的植物激素组合而不能使其愈伤组织分化成芽。IAA与6—BA的不同浓度组合对不定芽形成效果不明显。     

九连山常绿阔叶林乔木优势种群的种间关联性分析

九连山国家级自然保护区分布着原生的典型常绿阔叶林, 且已形成不同的优势群落, 目前尚不清楚群落乔木层中优势物种之间的作用关系。采用2×2联列表, 通过方差分析, χ²检验、Pearson相关系数和Spearman秩相关系数检验, 对九连山常绿阔叶林乔木层中重要值较高的28个优势种群、378个种对间的关联性进行定量研究。方差分析表明: 28个优势种群的总体种间关联性呈显著的正关联, 反映该群落处于较稳定的顶极阶段。不同检验结果表明: χ²检验结果有140个种对呈正相关, 238个种对呈负相关, 正负关联比为0.588; Pearson相关系数检验有104个种对呈正相关, 274个种对呈负相关, 正负关联比为0.380; Spearman秩相关系数检验有144个种对呈正相关, 234个种对呈负相关, 正负关联比为0.615; 与Pearson相关系数检验方法相比, Spearman秩相关系数检验具有较高的灵敏度。378个种对中, 绝大多数种对的联结关系未达到显著水平, 种对间的独立性相对较强, 这种种间联结的松散性可能与群落目前的发展阶段及物种本身的生态学特性有关, 各群落正处于稳定的顶极阶段。根据28个优势种群对环境的适应方式和主导生态因素, 可将它们划分为阳生植物和阴生植物两大生态种组。     

Selective ϖ-1 oxidation of fatty acids by CYP147G1 from Mycobacterium marinum

Background

Cyp147G1 is one of 47 cytochrome P450 encoding genes in Mycobacterium marinum M, a pathogenic bacterium with a high degree of sequence similarity to Mycobacterium tuberculosis and Mycobacterium ulcerans. Cyp147G1 is one of only two of these cyp genes which are closely associated with a complete electron transfer system.

Consistent detection of QTLs for crown rust resistance in Italian ryegrass (<Emphasis Type="Italic">Lolium multiflorum</Emphasis> Lam.) across environments and phenotyping methods

Crown rust, caused by Puccinia coronata f. sp. lolii, is one of the most important diseases of temperate forage grasses, such as ryegrasses (Lolium spp.), affecting yield and nutritional quality. Therefore, resistance to crown rust is a major goal in ryegrass breeding programmes. In a two-way pseudo-testcross population consisting of 306 Lolium multiflorum individuals, multisite field evaluations as well as alternative methods based on artificial inoculation with natural inoculate in controlled environments were used to identify QTLs controlling resistance to crown rust. Disease scores obtained from glasshouse and leaf segment test (LST) evaluations were highly correlated with scores from a multisite field assessment (r = 0.66 and 0.79, P < 0.01, respectively) and thus confirmed suitability of these methods for crown rust investigations. Moreover, QTL mapping based on a linkage map consisting of 368 amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) markers revealed similar results across different phenotyping methods. Two major QTLs were consistently detected on linkage group (LG) 1 and LG 2, explaining up to 56% of total phenotypic variance (V _p). Nevertheless, differences between position and magnitude of QTLs were observed among individual field locations and suggested the existence of specific local pathogen populations. The present study not only compared QTL results among crown rust evaluation methods and environments, but also identified molecular markers closely linked to previously undescribed QTLs for crown rust resistance in Italian ryegrass with the potential to be applied in marker-assisted forage crop breeding. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.