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排序方式: 共有121条查询结果,搜索用时 15 毫秒
1.
为满足水果追溯条码清晰、耐久的要求,选取橘子为试验对象,对比纳秒激光和皮秒激光在其表面打印二维码的效果。试验结果表明:与纳秒激光相比,皮秒激光在橘子表皮上打印的线条平直度佳,轮廓清晰,对表皮的损伤更小。 相似文献
2.
利用SSR技术鉴定西瓜甜瓜种子纯度 总被引:1,自引:0,他引:1
利用SSR分子标记技术对西瓜‘W1806’与甜瓜‘M1805’各3个批次及其亲本间的多态性进行引物筛选和种子的纯度鉴定。结果表明,在28对西瓜的SSR引物中,有5对引物在西瓜‘W1806’的F1代与亲本之间有很好的多态性。其中BVWS00839引物特异性好,条带清晰,父母本条带间隔明显,即作为3个批次的西瓜纯度鉴定的引物,其鉴定纯度分别为99.47%、98.96%和97.92%;在18对甜瓜的SSR引物中,只有1对CMBR052引物在F1代扩出的条带为典型的双亲互补型条带,故用该引物对甜瓜进行纯度鉴定,其纯度分别为97.90%、96.80%和97.40%。与田间鉴定结果的吻合率都在98%以上。这2个材料的吻合率说明SSR分子标记技术对西瓜和甜瓜纯度鉴定结果都是可靠的。 相似文献
3.
3种冷季型草坪草混播配方优化组合筛选试验 总被引:3,自引:0,他引:3
在河西走廊中部地区气候条件下,通过对草地早熟禾Poa pratensis、高羊茅Festuca arundinacea、多年生黑麦草Lolium perenne3种冷季型草坪草18种混播配方进行了成坪品质的观察测定,筛选出了适应当地气候条件的优化组合配方10个。 相似文献
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可见植入荧光标记和微金属线码标记标志拉萨裂腹鱼的研究 总被引:1,自引:0,他引:1
[目的]研究不同标记方法对拉萨裂腹鱼的标记效果,为其增殖放流与效果评估提供技术支撑。[方法]分别采用可见植入荧光标记(VIE)、微金属线码标记(CWT)和空白对照处理对拉萨裂腹鱼幼鱼(5~7 cm)进行为期40 d的标志试验,研究不同标记方法对拉萨裂腹鱼的标记效果。[结果] VIE组试验鱼的存活率明显高于CWT组和对照组。 VIE组和CWT组试验鱼的标志保持率分别为100%和98%。 VIE和CWT标记对试验鱼生长均没有显著影响。[结论] VIE标记是拉萨裂腹鱼幼鱼较适宜的短期标志方式。 相似文献
6.
Feasibility of using rare earth elements (REEs) to mark and identify escaped farmed Atlantic salmon Salmo salar L. 下载免费PDF全文
Marta Pérez de Nanclares Jens‐Erik Dessen Kjell‐Arne Rørvik Yngvar Thomassen Magny S Thomassen 《Aquaculture Research》2016,47(6):1885-1898
A series of rare earth elements (REEs) were evaluated as potential markers in scales of Atlantic salmon 1+ and 0+ smolt by addition of these elements to the feed. Chlorides of 5 REEs were tested, alone or in combination: lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd) and dysprosium (Dy). The labelled‐diets contained 125 or 250 mg REE kg?1 feed and were administered for up to 10 weeks. Fish scales were collected and analysed by inductively coupled plasma‐mass spectrometry (ICP‐MS) before start, 5 and 10 weeks after labelling started and finally 2 or 4 months after marking. The results demonstrated that the five tested elements were clearly incorporated into the scales of the fish fed the supplemented diets. Uptake and concentrations increased gradually during the feeding period, and no principal differences were found between the two smolt types. Combining 2 REEs in the same feed did not affect the incorporation of either of them. After a ‘dilution’‐period of 2–4 months the concentrations of all markers (except La) in the scales of the treated‐fish were still significantly higher than those of the untreated‐fish. The background concentrations of the tested markers and some other elements were also measured and found to give interesting information. 相似文献
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对家蚕多星纹基因ms的SSR标记定位分析 总被引:1,自引:0,他引:1
对家蚕幼虫斑纹突变多星纹基因ms进行分子标记定位,有益于对多星纹性状的分子标记辅助选择和对该基因的定位克隆研究。利用家蚕雌性染色体在减数分裂过程中不发生交换的特点,采用幼虫斑纹为素斑(p)的家蚕品系C108,幼虫斑纹为多星纹(ms)的家蚕品系g02,组配正反交群体(g02×C108)F1♀×g02♂和g02♀×(g02×C108)F1♂,分别记作BC1F和BC1M,利用已经构建的家蚕SSR分子标记连锁图谱中第12连锁群上的18对SSR标记引物在亲本间进行多态性筛选。BC1F群体中的普通斑个体均表现出与(g02×C108)F1相同的杂合型带型;而所有多星纹个体的带型与亲本g02一致,为纯合型。结果筛选出S1206、S1208、S1210、C5553S3共4个与家蚕ms连锁的SSR标记。利用BC1M群体构建家蚕ms及其连锁的SSR标记遗传连锁图,连锁图的图距为34.5 cM,4个SSR标记及ms的排列次序为S1206—S1208—S1210—C5553S3—ms,ms位于34.5 cM处,与ms最近的标记为C5553S3,遗传距离为12.4 cM。依据该SSR标记遗传连锁图谱可对ms进一步精确定位。 相似文献
9.
Marking springtails is a basic tool to evaluate their fundamental ecological phenomena. Rb marking is based on the fact that enriched rubidium in an organism can be tracked trough the experiment. Our goal was to improve the rubidium-marking technique in Folsomia candida (Willem) for both microcosm and field experiments. We investigated four methodological problems of this technique, in particular, we determined the required Rb concentration in the diet to reach marking level, measured the period when labeling could be detected under two different feeding conditions, and we estimated the effects of Rb on springtails' growth. Because marked and unmarked animals are always mixed in the course of recapture we also measured the levels of contamination between labeled springtails and those in the control groups. For introducing rubidium, we fed animals with Rb-treated Baker's yeast. Rubidium-chloride labeling persisted in springtails for 27 days during which the Rb-levels in marked animals remained distinguishable from those in unmarked ones. Rb-elimination rate depended highly on the feeding conditions, with Rb-elimination being faster when food was in excess. The fitted exponential model to Rb-elimination suggested that Rb-labeling may be used for 46 and 103 days for experiments with and without food respectively. We found no effect on Collembola growth at low Rb-levels (1.2 μg Rb/g dry yeast) but at higher concentration growth was reduced. We found that contamination occurred when springtails were stored together in glycerin, however the unmarked sample with the highest Rb content was still just 4.8% of the lowest marked sample. These results provide a basis for mark-release-recapture and other studies using Rb marking on springtails. 相似文献
10.
Abstract This study examined stocking with three early life stages of brown trout, Salmo trutta L., in the context of rehabilitating a native lineage. Experimental sections in five streams were stocked successively with three stages (I: unfed fry at the end of the reabsorption phase, II: fed fry measuring 2–3 cm and III: fed fry measuring 4–5 cm) derived from a hatchery stock bred from wild spawners. The three stages were distinguished by single or multiple fluoromarking of the otoliths with alizarin redS. The index of relative stocking efficiency was greater for stage II than for stage I in all sections and equivalent or greater than that for stage III. Stage II achieved significantly larger mean length and weight in autumn than stage III stockings. 相似文献