南阳牛Gli3基因多态性及其与生长性状的相关性

Gli3基因是Gli-Kruppel家族中的一员,其参与的Sonic hedgehog信号通路在动物生长发育,特别是早期生长发育过程中有重要作用.利用PCR-SSCP和DNA测序技术研究了187头纯种南阳牛Gli3基因编码区4个位点(E4、E5、E6和E7)的多态性,发现E4和E5位点存在SSCP多态.对不同SSCP带型的对应片段进行了测序分析,共发现3个新的SNP多态位点(T123600C、T123696C和A128688G),其中第123600和第123696两个位点处于连锁状态.E5位点处于Hardy-Weinberg平衡状态,E4位点处于非平衡状态.不同基因型与生长发育性状的相关性分析显示,E4位点上,CC基因型个体的六月龄体重、胸围、坐骨端宽、日增重指标显著大于TT基因型个体(P<0.05),该位点有可能作为南阳牛早期生长性状标记辅助选择的标记之一.     

A real-time PCR assay for detection and quantification of Verticillium dahliae in spinach seed

Verticillium dahliae is a soilborne fungus that causes Verticillium wilt on multiple crops in central coastal California. Although spinach crops grown in this region for fresh and processing commercial production do not display Verticillium wilt symptoms, spinach seeds produced in the United States or Europe are commonly infected with V. dahliae. Planting of the infected seed increases the soil inoculum density and may introduce exotic strains that contribute to Verticillium wilt epidemics on lettuce and other crops grown in rotation with spinach. A sensitive, rapid, and reliable method for quantification of V. dahliae in spinach seed may help identify highly infected lots, curtail their planting, and minimize the spread of exotic strains via spinach seed. In this study, a quantitative real-time polymerase chain reaction (qPCR) assay was optimized and employed for detection and quantification of V. dahliae in spinach germplasm and 15 commercial spinach seed lots. The assay used a previously reported V. dahliae-specific primer pair (VertBt-F and VertBt-R) and an analytical mill for grinding tough spinach seed for DNA extraction. The assay enabled reliable quantification of V. dahliae in spinach seed, with a sensitivity limit of ≈1 infected seed per 100 (1.3% infection in a seed lot). The quantification was highly reproducible between replicate samples of a seed lot and in different real-time PCR instruments. When tested on commercial seed lots, a pathogen DNA content corresponding to a quantification cycle value of ≥31 corresponded with a percent seed infection of ≤1.3%. The assay is useful in qualitatively assessing seed lots for V. dahliae infection levels, and the results of the assay can be helpful to guide decisions on whether to apply seed treatments.     

Development of a multiparent advanced generation intercross (MAGIC) population for genetic exploitation of complex traits in Brassica juncea: Glucosinolate content as an example

Multiparent advanced generation intercross (MAGIC) populations have recently been developed to allow the high-resolution mapping of complex quantitative traits. This article describes the development of one MAGIC population and verifies its potential application for mapping quantitative trait loci (QTLs) in Brassica juncea. A total of 170 RILs were genotyped using 346 intron length polymorphism (ILP) polymorphic markers. The population lacks significant signatures of population structure that are suitable for the analysis of complex traits. Genome-wide association mapping (GWAS) identified three major glucosinolate (GSL) QTLs of QGsl.ig01.1 on J01 for indole GSL (IG), QGsl.atg09.1 on J09 and QGsl.atg11.1 on J11 for aliphatic GSL (AG) and total GSL (TG). The candidate genes for QGsl.ig01.1, QGsl.atg09.1 and QGsl.atg11.1 are GSH1, GSL-ALK and MYB28, which are involved in converting glutamate and cysteine to γ-EC, the accumulation of glucoraphanin and the whole process of AG metabolism, respectively. In addition to its QTL mapping purpose, the MAGIC population could also be potentially utilized in variety development by breeders.     

Stream water quality and its influencing factor in lower order streams in upriver sections of Ashihe River

For understanding the reasons that caused the degradation of water quality in lower order streams, systematic sampling was conducted at different spatial locations aiong the low order streams （1 st-5th） of Ashihe River continuum in Maoershan Experimental Forest of Northeast Forestry University, Sharlgzhi City, Heilongjiang Province, China. The indexes of stream water quality, i.e., the pH, dissolved oxygen（DO）, turbidity, temperature, PO43-P, NO3-N and NH4^＋-N concentrations, total dissolved inorganic nitrogen （TDIN-N, including concentrations of NO3^＋-N and NH4^＋-N）, and total phosphorus （inorganic and organic phosphorous, TP） were measured and analyzed. The stream order, related environmental settings and land-use type were recorded for each sampling location. The indexes of stream water quality at different locations with different stream orders and land use types were compared by ANOVA analysis. The indexes of stream water quality at different sampling locations were analyzed by Hierarchical cluster analysis. Result showed that water quality had significant difference in different stream orders and land use types; some locations with different stream features （stream order and land use type） were grouped into same clusters, indicating that random disturbances produced the variations in water quality, which made the spatial variances of stream water quality inconsistent with the general rules.     

降香黄檀在肇庆市属国有林场适生性评价

薇甘菊是一种危害严重的外来入侵物种,也是我国林业检疫性有害生物。文章根据薇甘菊的生物学特性,选择对菊科植物有高活性的药剂成分进行复配研制药剂,经室内和林间的药效试验,筛选出能高效防治薇甘菊且对环境安全的新药剂——24%二氯吡啶酸·2,4-滴水剂,商品名为"紫薇清"。     

泽兰实蝇研究进展

泽兰实蝇是紫茎泽兰的专食性天敌,许多遭受紫茎泽兰危害的国家把泽兰实蝇当作紫茎泽兰的一种重要防治手段.文章从泽兰实蝇的引种、生物学特性、生态学特性和对紫茎泽兰的控制等方面对泽兰实蝇的研究概况进行综述,针对泽兰实蝇的防效不够高、解毒机制不明确等问题,提出深入研究泽兰实蝇的寄主选择机制及种群扩散规律,开展解毒蛋白和共生菌研究,以及对本土寄生蜂的寄生规律和选择机制开展研究等建议.     

小麦种子活力及其遗传分析

用生理法测定不同类型小麦品种(系)的种子活力,并探索种子活力与环境条件的关系。试验表明,种子活力强度决定于基因型,但又随环境因素而变化。不同品种具有不同的种子活力,同一品种也因不同的环境条件而形成活力不同的种子。种子活力的遗传力较高,选用高活力的品种杂交,可以从遗传基础上提高种子活力,选育成高活力的新品种。小麦种子活力高,田间出苗和成苗率也高。种子的容重、千粒重和体积与品种活力的相关性不显著,而蛋白质和氨基酸含量则与活力有极显著的相关性。     

珠江三角洲三水市种植业耕作模式的综合评价

采用层次分析法对广东三水市种植业18种耕作模式进行综合评价。结果表明，生态效益和经济效益相互协调的模式有：稻-荸荠、菜-萝卜-萝卜、瓜-豆-番茄和瓜-豆-菜等；两效益相互矛盾的模式有：瓜-瓜-菜-较好的发展前途。但有待优化作物结构和管理技术，提高系统功能和效益。     

营养对早期断奶仔猪免疫功能及健康的影响

本文阐述了饲料中主要营养物质(蛋白质、氨基酸、糖类、脂肪、矿物质和维生素)对早期断奶仔猪免疫功能和健康的影响。     

灰色理论在魔芋种质资源创新评价及育种中的应用

应用灰色理论对5份魔芋种质资源的6个主要农艺性状进行分析,评价创新种质的综合表现及各主要农艺性状的相互关系,以期为魔芋新品种选育提供科学依据。关联分析结果表明展开度、株高、叶片长是影响产量的主要因子。