网箱养鳝水体适宜水生植物的筛选

从经济价值、对水深的适应性及植株扩展度3个方面对长江流域适宜种植的23种水生植物进行了筛选．认为菜用睡莲（咖n加aeaspp．）、蕹菜（昂0埘0eaaquatiea）、菱角（Trapaspp．）及芡实（Euryaleferox）4种水生经济植物比较适合于网箱养蟮水体种植,并提出了相应的栽培技术要点。     

Quality of Highbush Blueberry (Vaccinium corymbosum L.) and Bilberry (Vaccinium myrtillus L.) Jam

ABSTRACT

Jam from wild bilberries and from the blueberry culti vars ‘Bluecrop’ and ‘Berkeley’ were analyzed by means of sensory profiling and by instrumental measurement of anthocyanins, color, pH and soluble solids. The study shows that bilberry jam has more “bluish black color,” compared to a more “reddish-blue color” and “glossy” surface of the jam from cultivated blueberries. Bilberry jam was less “smooth” and higher in “viscosity” and “berry density” as well as less distinct in “flavor of flowers and fruits,” while the “blueberry flavor and odor” were more distinct in the bilberry jam than that made of highbush blueberries. Analysis of color by means of sensory hue and instrumental a Hunter lab corresponded well, as did saturation measured by the sensory method and chroma instrumentally measured.     

基于RNA-seq技术挖掘鹌鹑羽色自别雌雄相关基因

鹌鹑的羽色自别雌雄现象是由性染色体上的基因决定的,但具体的分子机制未知.本研究以北京白羽公鹌鹑和朝鲜栗羽母鹌鹑为研究对象,利用RNA-seq技术分析了F1公鹑和F1母鹑胚胎期第10天皮肤组织样品的转录组,以筛选调控鹌鹑羽色自别雌雄的关键基因,并利用qRT-PCR技术进行验证.结果表明:RNA-Seq共得到38.94 G...     

利用SLAF-seq结合BSA方法发掘大豆种皮色相关基因

种皮色不仅是一个形态标记,还是一种重要的进化性状,与大豆商品性、营养价值以及抗性关系密切。本研究以黄色种皮大豆品系BMY及其褐色种皮衍生品系BMZ为亲本,从F2群体中分别挑选出黄色种皮和褐色种皮的植株各9株,构建了两个极端性状混合池DNA文库,借助SLAF-seq和BSA技术,挖掘大豆种皮色性状相关候选基因。对于26121个高质量SNP位点,利用SNP-index方法和ED方法进行综合分析,获得8个与目标性状紧密关联的候选区域,分别位于第5、11、12、19和20染色体,包含620个编码基因。对这620个基因进行进一步的功能注释,NR、Swiss-Prot、GO、KEGG和COG数据库分别注释到600、518、533、133和256个基因,其中存在非同义突变基因4个,分别为Glyma05g005600、Glyma05g009700、Glyma12g006100和Glyma12g047300。候选区域内编码基因的深度注释有助于功能基因的进一步分离,为大豆种皮色性状相关基因的精细定位及克隆提供理论依据。     

Effects of White Clover Inclusion on Turf Characteristics,Nitrogen Fixation,and Nitrogen Transfer from White Clover to Grass Species in Turf Mixtures

Abstract

An irrigated field trial was conducted to test the effects of white clover in three turfgrass species (perennial ryegrass, Kentucky bluegrass, and creeping bentgrass) on color, clipping yield, and botanical composition and to estimate nitrogen (N)₂ fixation and N transfer from white clover to associated turfgrass species under different N‐fertilization conditions in 1999–2002.

Nitrogen fertilizers significantly increased color ratings in all observations. Grass–white clover mixtures had better color ratings than pure grass at all sampling dates and seasonal averages in unfertilized conditions. Fertilized pure grass plots yielded significantly more than control plots in all turfgrass species. Nitrogen fertilization did not affect clipping yield greatly in turfgrass–white clover mixtures. Nitrogen application significantly decreased white clover percentage in the harvested clippings in second and third year.

Nitrogen fertilization increased tissue N concentration positively in all turfgrass species grown alone. In contrast, N fertilization did not greatly affect tissue N concentration of either turfgrass species or white clover in the mixtures. Nitrogen fixation of white clover was estimated as 24.6, 30.7, and 33.8 g m^?2 year^?1 in perennial ryegrass, Kentucky bluegrass, and creeping bentgrass, respectively. The total estimated N₂ fixation gradually decreased with increasing N fertilization. Nitrogen transfer from white clover to the associated turfgrass varied from 4.2 to 13.7% of the total N that the white clover fixed annually.     

Use of Chromameter‐Measured Color Parameters in Estimating Color‐Related Soil Variables

Abstract

Soil color is a soil property that may be used as an interpreting index in estimating processes and properties. Quantifying color allows one to obtain information for rapidly estimating the related processes in soils. CIELAB color parameters L*, a*, and b* of ground (air‐dried and sieved) soil samples and aggregate surfaces of four soil profiles formed in calcareous colluviums in northern Turkey were analyzed. Values of color parameters measured in ground and intact soils were compared and related to soil properties by the regression technique. Results revealed that the L* value obtained with a ground soil sample was a significant predictor of organic matter in A horizons (p < 0.001). Although calcic horizons yielded the highest L* values, no significant relationship was obtained between calcium carbonate contents and lightness of soils in any of horizons studied. The parameters of b* could adequately be used to quantify dithionite‐extractable iron oxide contents in soils studied. The results further showed that the CIELAB color parameters obtained with ground samples were more informative than that of aggrevated samples in relating color parameters to soil properties.     

基于计算机视觉的大菱鲆对背景色选择习性研究

为了探讨大菱鲆幼鱼对于不同背景色的选择习性,该文首先通过9格颜色试验发现大菱鲆幼鱼偏好淡紫色,而出现在黑色和红色背景累积频率较低;同时通过计算机视觉分析发现,幼鱼在黑色和红色背景下体表明度变化速率远比在紫色和粉色背景下剧烈,证明了黑色和红色背景对幼鱼胁迫更大,其需要调动更多激素来调整生理响应,以改变体色适应新的背景环境。因此建议养殖池的颜色尽量采用浅色,不要使用黑色等深色作为养殖背景颜色,研究结果可为养殖系统设计和生产管理提供参考依据。     

普通丝瓜果皮颜色性状的遗传研究

对普通丝瓜的果皮颜色性状进行遗传分析,旨在为果皮颜色控制基因的挖掘及外观品质改良提供理论依据。以绿果皮丝瓜材料YX014和白果皮高代自交系丝瓜材料LJ-01为亲本,配制成P₁、P₂、F₁、F₂、B₁、B₂等6个世代,通过目测的方法对6个世代单株的丝瓜果皮色性状观察和分级处理,应用植物数量性状主基因+多基因混合遗传模型对丝瓜果皮色性状进行遗传规律分析。结果表明,普通丝瓜果皮颜色的最佳遗传模型为B-1,即符合2对主基因控制并表现为加性-显性-上位性遗传模型。B₁、B₂和F₂分离世代的主基因遗传率较高,分别为96.4%、99.1%和99.4%。此外,2对主基因的加性效应分别为-2.50和0.00,显性效应分别为0.50和0.48,说明第一对主基因在加性效应中占主导地位,且为负向效应,2对主基因的显性效应近似相等。控制普通丝瓜果皮色的主效基因的遗传力较高,普通丝瓜果皮色遗传改良可以在早期分离世代时进行。     

基于阈值分割法的茶叶嫩芽识别研究

嫩芽识别是实现名优茶智能采摘的前提,因此,利用数码相机采集了清明时期贵州大学和贵州农科院茶园茶叶图像,并以茶叶图像为对象,研究了茶叶嫩芽的识别方法。首先对1KGB颜色模型的色差法（R—B）进行分析,然后以该算子为分割分量,对比研究了多种阈值分割法的优缺点和分割效果。试验结果表明,所研究的分割方法都能有效区分嫩芽和背景,其中ostu法和迭代阈值法的识别效果较好,嫩芽识别准确率为90％左右。     

水稻淡黄叶突变体安农标810S的发现及初步研究

安农标810S是2003年冬在海南三亚安农810S繁殖田中发现的具有淡黄叶标记性状的自然突变体,2006年8月通过湖南省科技厅技术鉴定。安农标810S性状稳定,全生育期整株叶片均表现淡黄绿色,其它农艺性状、育性和配合力等与安农810S基本一致。其淡黄叶标记性状受1对隐性基因控制,易于转育新的水稻光温敏核不育系,有利于两系杂交水稻制种除杂保纯和杂交种子纯度快速鉴定,对降低两系杂交水稻种子生产中的纯度风险具有重要的育种价值。