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281.
基于SSILP、InDel和SSR标记的杂草稻籼粳分类   总被引:1,自引:0,他引:1  
 采用40对SSILP、30对InDel和43对SSR标记对来自斯里兰卡的28份杂草稻和14栽培稻,来自国内外的9份籼型栽培稻、7份粳型栽培稻和4份代表性杂草稻进行遗传多样性分析。SSILP、InDel和SSR标记分别检测到84、61和213个等位基因,其平均多态性信息含量(PIC)分别为0.257、0.255和0.543。聚类分析显示供试的42份斯里兰卡杂草稻和栽培稻均为籼型。SSILP与InDel标记的相关性很高(r=0.989),而它们与SSR标记相关性较低(0.812和0.808)。结果表明,SSILP和InDel标记可高效鉴别各类稻种资源的籼粳属性,而SSR标记更适用于亚种内的分类。  相似文献   
282.
世界不同地理来源粳稻品种的遗传相似性研究   总被引:13,自引:3,他引:10  
 【目的】探讨不同国家(或地区和组织)间粳稻选育品种的遗传相似性和遗传差异,旨在为世界各地的粳稻品种能够有效利用于水稻育种提供科学依据。【方法】利用34对SSR引物对不同地理来源包括20个国家(或地区和组织)的313份粳稻选育品种进行遗传相似性和聚类分析。【结果】共检测到198个等位基因,平均每对SSR引物检测到的等位基因数为5.8235个。RM320、RM531、RM1、RM21和RM336的等位基因数较多,分别为16、13、12、10和10个;RM320、RM336、RM286、RM531和RM21的遗传多样性指数较高,分别为2.3668、2.0041、1.9684、1.9508和1.7203。各国家(或地区和组织)粳稻选育品种的遗传相似系数变异范围为0.279~0.918,平均值为0.653。纬度和地理位置相近的国家间粳稻品种的遗传相似系数较大,基本聚为同一个类群,而纬度差异较大,地理位置较远的国家间粳稻品种的遗传相似系数较小,聚为不同类群。 【结论】粳稻品种的遗传相似性与纬度和地理位置有着密切的联系。  相似文献   
283.
水稻蛋白质含量的遗传研究进展   总被引:6,自引:0,他引:6  
 蛋白质含量的高低是衡量稻米营养价值的主要指标之一,因此提高蛋白质含量是稻米营养品质育种的重要目标。本文阐述了水稻蛋白质种类、氨基酸组成及其营养价值,并概括了水稻不同基因型和不同部位或组织间蛋白质含量的差异、蛋白质含量的遗传及分子机理以及种质创新的研究现状,可为水稻蛋白质含量的深入研究和高蛋白种质创新提供参考。  相似文献   
284.
茶叶中硫丹及硫丹硫酸酯的ELISA快速测定   总被引:3,自引:0,他引:3  
研究应用酶联免疫方法,快速检测茶叶中硫丹及硫丹硫酸酯。茶叶提取后,不净化,用PBS缓冲液稀释500倍后,进行酶联免疫方法测定,方法平均回收率为86.6%~91.1%;经SPE净化后,回收率68.7%~123%。标准曲线IC50为2βµg/L,线性范围1~10βµg/L。直接提取法最低检测限2βmg/kg,净化法为0.06βmg/kg。经气相色谱/质谱联用方法验证,灵敏度、精密度和准确度均符合快速检测要求。该法具有快速、简便、低耗、易操作等特点。  相似文献   
285.
This study was conducted to investigate the influence of dietary lipid source and n‐3 highly unsaturated fatty acids (n‐3 HUFA) level on growth, body composition and blood chemistry of juvenile fat cod. Triplicate groups of fish (13.2 ± 0.54 g) were fed the diets containing different n‐3 HUFA levels (0–30 g kg?1) adjusted by either lauric acid or different proportions of corn oil, linseed oil and squid liver oil at 100 g kg?1 of total lipid level. Survival was not affected by dietary fatty acids composition. Weight gain, feed efficiency and protein efficiency ratio (PER) of fish fed the diets containing squid liver oil were significantly (P < 0.05) higher than those fed the diets containing lauric acid, corn oil or linseed oil as the sole lipid source. Weight gain, feed efficiency and PER of fish increased with increasing dietary n‐3 HUFA level up to 12–16 g kg?1, but the values decreased in fish fed the diet containing 30 g kg?1 n‐3 HUFA. The result of second‐order polynomial regression showed that the maximum weight gain and feed efficiency could be attained at 17 g kg?1 n‐3 HUFA. Plasma protein, glucose and cholesterol contents were not affected by dietary fatty acids composition. However, plasma triglyceride content in fish fed the diet containing lauric acid as the sole lipid source was significantly (P < 0.05) lower than that of fish fed the other diets. Lipid content of fish fed the diets containing each of lauric acid or corn oil was lower than that of fish fed the diets containing linseed oil or squid liver oil only. Fatty acid composition of polar and neutral lipid fractions in the whole body of fat cod fed the diets containing various levels of n‐3 HUFA were reflected by dietary fatty acids compositions. The contents of n‐3 HUFA in polar and neutral lipids of fish increased with an increase in dietary n‐3 HUFA level. These results indicate that dietary n‐3 HUFA are essential and the diet containing 12–17 g kg?1 n‐3 HUFA is optimal for growth and efficient feed utilization of juvenile fat cod, however, excessive n‐3 HUFA supplement may impair the growth of fish.  相似文献   
286.
优糖稻2号系由上海市农业科学院作物育种栽培研究所利用系谱法选育而成的一个富含抗性淀粉的功能水稻新品种,2019年通过上海市农作物品种审定委员会审定。优糖稻2号抗性淀粉含量高达13.1%。抗性淀粉是在健康者小肠中不被吸收的淀粉及其降解产物的总称,具有控制血糖、预防肠道疾病、控制体质量、促进维生素和矿物质吸收等重要的生理功能。本文介绍了优糖稻2号的选育经过、产量表现、主要特征特性及栽培技术要点。  相似文献   
287.
This study aimed to investigate the effect of mydriasis using topical rocuronium bromide on electroretinography (ERG) in domestic pigeons (Columba livia). Scotopic mixed rod and cone, photopic cone, and photopic flicker ERG were performed on nine eyes of nine healthy adult pigeons under sedation. Each pigeon underwent two sets of ERG recordings. First, without the induction of mydriasis (control) and the second time with the induction of mydriasis using topical rocuronium bromide (treatment). The results were compared using either the Student’s t-test or Wilcoxon rank-sum test, where a P-value of <0.05 was considered statistically significant. No significant differences were observed in the a- and b-wave implicit times and amplitudes during scotopic ERG between the two groups. The a- and b-wave amplitudes in the photopic cone were significantly higher in the treatment group (63.83 ± 32.33 and 191.75 ± 94.46 µV) compared to the control group (46.15 ± 27.60 and 116.76 ± 70.65 µV; P=0.045 and P=0.032, respectively). The photopic flicker amplitude was also significantly higher in the treatment group (76.23 ± 48.56 µV) than in the control group (42.18 ± 31.18 µV; P=0.044). No statistically significant differences were observed in the photopic cone and flicker implicit times between both groups. In conclusions, mydriasis induced by rocuronium bromide in pigeon resulting in higher amplitudes during the photopic ERG but not scotopic ERG.  相似文献   
288.
The alpha-macroglobulins are broad-specificity protease inhibitors important in the regulation and clearance from circulation of biologically active proteases. Inappropriate protease activation may be a feature of canine acute pancreatitis and the ability of the animal to clear these proteases may be important in determining survival. An enzyme immunoassay for the detection and measurement of canine alpha-macroglobulins in plasma samples was developed. A reference range for the canine alpha-macroglobulins of 1.20-2.72 mg ml-1 was established from a panel of canine plasma samples, and the stability of the alpha-macroglobulins in plasma samples stored at 4 degrees C was investigated. Changes in the level of the alpha-macroglobulins during disease states involving increased endogenous protease activity can now be investigated using a rapid, repeatable and quantifiable assay.  相似文献   
289.
小波变换与分水岭算法融合的番茄冠层叶片图像分割   总被引:1,自引:0,他引:1  
在基于机器视觉的作物营养诊断研究中,通常需要采集叶片样本并在实验室条件下定量测定其营养素含量,但由于叶片间相互重叠,往往使得叶片样本不能清晰地反映在群体番茄冠层图像中。为了解决这一问题,需要利用图像分析技术有效提取作物冠层图像中的叶片,并根据处理结果采集实验室测定样本。本文从复杂背景剔除、梯度图计算、小波变换、标记选取、分水岭分割等环节出发,实现了基于小波变换与分水岭算法融合的番茄冠层多光谱图像叶片分割。首先对比了4种复杂背景剔除算法,发现当增强因子a=1.3时,基于归一化植被指数(Normalized difference vegetation index,NDVI)的阈值分割目标提取准确,适合各种光照条件,时空复杂度低。其次在梯度图计算方面,近红外(Near infrared,NIR)波段图像形态学梯度在保持目标边缘的同时,能消除大量由叶脉、光照等引起的叶片内纹理细节。然后以小波分析为基础进行标记选取,发现当选取db4小波函数、4层小波分解低频系数、阈值为18的H-maxima变换能得到最优的目标标记结果。最后对多光谱番茄冠层图像的小波变换分水岭分割和数学形态学分水岭分割结果进行叠加,发现对复杂背景及不同光照强度下的番茄冠层叶片平均误分率为21%,为基于多光谱图像分析的番茄叶片营养素含量检测提供了一定的技术支持。  相似文献   
290.
Abstract An experimental fishway was used to examine adult Pacific lamprey, Lampetra tridentata (Gairdner), behaviour in a series of attraction and passage‐performance tests. Among all experiments, lamprey oriented to the fishway floor and walls and were attracted to both ambient and concentrated flow. When confronted with high‐velocity areas (vertical‐slot and submerged‐orifice weirs), many lamprey failed to pass upstream. However, lamprey were able to find and take advantage of low‐velocity refuges when they were provided. Lamprey climbed shallow‐ and steep‐angled ramps when attraction cues were sufficient and other passage routes were restricted. The combined results demonstrated the passage challenges that fishways designed and operated for salmonids present to non‐salmonid species. They also highlight the importance of evaluating trade‐offs between fishway attraction and passage efficiency. The experiments were integrated with tagging studies and development of lamprey‐specific passage structures, a research combination that provided an effective template for fishway performance evaluations.  相似文献   
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