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排序方式: 共有203条查询结果,搜索用时 15 毫秒
1.
栽培稻和普通野生稻居群根表铁膜形成能力的比较研究   总被引:1,自引:0,他引:1  
根表铁膜形成能力反映了水稻根系氧化力的强弱。为了了解普通野生稻根系氧化力,采用水培铁胁迫试验对5个水稻品种和2个普通野生稻居群根表铁膜形成能力进行评价。结果表明:同亚洲栽培稻相比,普通野生稻拥有较高的根孔隙度,但其根表铁膜含量较低;供试植株的根孔隙度与根表铁膜含量之间没有相关性,这很可能与侧根的数量有关。  相似文献   
2.
Single‐nucleotide polymorphisms (SNPs) are rapid, economical and reliable genotyping tools. Non‐heading Chinese cabbage (Brassica rapa L. subsp. chinensis Makino) is now an economically important vegetable crop worldwide. In this study, 1,167 SNPs were evaluated for 7polymorphism among 70 representative non‐heading Chinese cabbage inbred lines using a Kompetitive Allele Specific PCR (KASP) genotyping assay. On the basis of identified polymorphisms and the results of a principal component analysis, we selected 50 core SNPs that were balanced sufficiently to provide adequate information for genetic identification. The core SNPs were used for construction of a neighbour‐joining dendrogram that separated the 70 inbred lines into four main groups and several subgroups corresponding to Caixin, Heiyebaicai, Huangxinwu, Naibaicai, Taitsai, Pak‐choi, and Wutatsai. This categorization was superior to that achieved using a dataset of 479 polymorphic SNPs. To confirm the utility of the core SNP markers in genetic identification, we tested their stability and resolution using 162 commercial hybrid cultivars. The SNPs, which represent a cost‐effective, accurate marker set for germplasm analysis and cultivar identification, are suitable for molecular marker‐assisted breeding in non‐heading Chinese cabbage.  相似文献   
3.
油菜籽中含有多种具有抗氧化活性的物质,为抵御机体的氧化损伤起到了积极作用。本文综述了油菜籽来源的诸多抗氧化活性成分及抗氧化活性的评价方法。油菜籽主要的抗氧化成分有肽类、多酚类、多糖类、生育酚和其它抗氧化成分,其中的肽类主要有三种产生方式:非消化酶酶解、消化酶酶解和发酵。针对油菜籽来源的活性物质抗氧化活性的评价方法,包括体外测定方法(化学检测)和细胞内抗氧化实验和动物实验。综述还探讨了油菜籽抗氧化活性成分研究中存在的问题和解决方法,旨在为油菜籽活性成分的开发和利用提供参考。  相似文献   
4.
Orf virus (ORFV), a member of parapoxvirus, is an enveloped virus with genome of double-stranded DNA. ORFV causes contagious pustular dermatitis or contagious ecthyma in sheep and goats worldwide. In general, detection of viral DNA and observing ORFV virion in tissues of afflicted animals are two methods commonly used for diagnosis of orf infection; however, isolation of the ORFV in cell culture using virus-containing tissue as inoculum is known to be difficult. In this work, the ORFV (Hoping strain) isolated in central Taiwan was successfully grown in cell culture. We further examined the biochemical characteristic of our isolate, including viral genotyping, viral mRNA and protein expression. By electron microscopy, one unique form of viral particle from ORFV infected cellular lysate was demonstrated in the negative-stained field. Moreover, immunomodulating and anti-influenza virus properties of this ORFV were investigated. ORFV stimulated human monocytes (THP-1) secreting proinflammatory cytokines IL-8 and TNF-α. And, pre-treatment of ORFV-infected cell medium prevents A549 cells from subsequent type A influenza virus (IAV) infection. Similarly, mice infected with ORFV via both intramuscular and subcutaneous routes at two days prior to IAV infection significantly decreased the replication of IAV. In summary, the results of a current study indicated our Hoping strain harbors the immune modulator property; with such a bio-adjuvanticity, we further proved that pre-exposure of ORFV protects animals from subsequent IAV infection.  相似文献   
5.
红曲米是福建红曲黄酒酿制过程中重要的糖化发酵剂。发酵力是衡量酿造用红曲品质的一个重要指标。研究通过酒精测定法和二氧化碳失重法测定酿造用红曲的发酵力,以评价2种发酵力测定方法的可行性。结果表明,二氧化碳失重法更适合于红曲米发酵力的测定。研究还对福建省20个红曲米的发酵力进行了测定,结果表明用二氧化碳生成量能够很好地表征红曲米发酵力的强弱。红曲米发酵力测定方法可行性分析对红曲米相关标准的制定具有重要意义。  相似文献   
6.
Vegetative compatibility (vc) and mating types and genetic diversity of Cryphonectria parasitica isolates were determined using 183 isolates obtained from 215 infected chestnut trees growing in 13 provinces of Turkey. Based on the cultural aspects, 143 of these isolates were evaluated as virulent whereas the remaining 40 isolates were hypovirulent. When vc types of 183 isolates were classically differentiated, 135 of them matched to EU-1 (82.3%), 29 of them to EU-12 (17.6%) vc type, whereas 19 of them did not match to the two. When molecular vic markers were used, all the isolates were assigned to two EU vc types; 149 to EU-1 (81.4%) and 34 (18.5%) to EU-12. Of the majority of the isolates, 134 (73.2%) had mating-type MAT-1, while 44 (24%) isolates had MAT-2 and 5 (2.8%) isolates had both mating types. The population analysis based on two DNA marker systems, Inter-Primer Binding Site and Start Codon Targeted Polymorphism, showed no intraspecific genetic variation among the C. parasitica isolates. The prevalence of two dominant vc types revealed by this study shows that biological control with hypovirulent EU-1 and EU-12 isolates will be significant for the country. The results might be helpful to chestnut breeders carrying out resistance breeding studies to manage this disease based on hypovirulence attributed to Cryphonectria hypovirus 1.  相似文献   
7.
8.
Bodo R. Trognitz 《Euphytica》1991,56(2):143-148
Summary The main obstacle in breeding potato (Solanum tuberosum L.) dihaploids is the severe limitation of male fertility. To determine pollen viability assays that correlate well to fertility in crosses, results of five different pollen viability assays were compared by correlation analysis with fruit and seed set characters in test crosses, and to pollen tube growth in situ (PL-test). The methods used were: staining the pollen cells with carmino acetic acid (CAA-test); in vitro pollen germination (PG-test); and detection of pollen staining rates after incubation with fluoresceine diacetate (FDA-test), 2-3-5-triphenyle tetrazolium chloride (TTC-test), and 5-bromo-4-chloro-3-indolyle--galactoside (X-Gal-test).The results of test crosses and pollen tube growth in situ correlated with the results of all other assays with the following ranking, from highest to lowest: enzyme activity assays (X-Gal-test, FDA-test, TTC-test), in vitro pollen germination (PG-test), and pollen staining by CAA. The newly developed X-Gal-test for monitoring -galactosidase activity showed the least variation of all assays investigated. Thus, this highly reproducible simple procedure is recommended for male fertility screening.Abbreviations B/F Berries obtained per 100 flowers - CAA Carmino acetic acid - FDA Fluoresceine diacetate - PG Pollen germination rate in vitro - PL Pollen tube growth in situ - S/B Seeds per berry - S/F Seeds per pollinated flower - TTC 2-3-5-triphenyle tetrazolium chloride - X-Gal 5-bromo-4-chloro-3-indolyle--galactoside  相似文献   
9.
干湿交替对作物根际特征及铁膜形成的影响研究进展   总被引:4,自引:0,他引:4  
于晓莉  傅友强  甘海华  沈宏 《土壤》2016,48(2):225-234
铁膜普遍存在于水生植物的根系表面,根际周围Fe~(2+)的浓度和根系氧化力决定了根表铁膜的数量。干湿交替是农业生产中常用的灌溉技术。在干湿交替过程中,水分和氧气含量的变化导致根际土壤发生一系列物理、化学和生物学变化,从而对根表铁膜的形成产生影响。本文综述了干湿交替过程对根际特征变化的影响,分析了根表铁膜的形成条件、化学组成与空间结构和根表铁膜的形成过程,并在此基础上探讨了干湿交替对铁膜形成的影响以及干湿交替诱导铁膜形成的可能机制。最后对干湿交替诱导铁膜形成的研究方法与应用前景进行了展望。  相似文献   
10.
不同铁形态对水稻根表铁膜及铁吸收的影响   总被引:5,自引:0,他引:5  
通过溶液培养试验研究了FeCl2?4H2O和FeCl3?6H2O对水稻根表铁膜数量及铁吸收的影响。结果表明,FeCl2处理时水稻根表铁膜浓度是FeCl3处理的197%~233%。利用EDTA-BPDS对铁膜形态分析看出,根表铁膜中Fe3+占85%~92%,Fe2+占8%~15%。水稻天优998根表铁膜数量显著高于培杂泰丰,其铁吸收是培杂泰丰的115%~138%。两种铁形态处理明显提高水稻的根系活力,其中,FeCl2处理时水稻根系活力增加24%~69%,FeCl3为16%~54%。FeCl2处理时水稻根系SOD、POD和CAT活性分别增加11%~32%、15%~30%和30%~31%,但FeCl3处理没有明显影响。上述结果表明一定浓度铁处理明显增加水稻根表铁浓度和铁吸收;与FeCl3处理相比,FeCl2处理能提高根系抗氧化酶活性,增加水稻的铁吸收和根表铁膜数量。  相似文献   
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