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1.
为了解中国不同麦区小麦种质资源籽粒脂肪氧化酶(lipoxygenase,LOX)活性相关基因TaLox-B1的差异和分布,利用小麦4B染色体上的功能标记LOX16和LOX18对7个麦区的436份种质资源进行分子检测。结果表明:在供试材料中共检测到3种TaLox-B1基因等位变异类型,分别为TaLox-B1a(与高LOX活性相关)、TaLox-B1b(与低LOX活性相关)和杂合型,其频率分别为19.0%、70.4%和10.6%。小麦LOX活性基因不同变异类型在各生态区的分布存在明显差异:基因型TaLox-B1a在黄淮冬麦区、北部冬麦区和长江中下游冬麦区分布较多,其比例分别为21.1%、19.8%和17.6%;基因型TaLox-B1b在西南冬麦区和长江中下游冬麦区分布较多,比例分别为87.9%、72.5%;杂合型仅存在于北部冬麦区、黄淮冬麦区与长江中下游冬麦区,比例分别为14.2%、12.4%和9.8%。利用标记LOX16和LOX18对53个自选高代品系进行分子检测,发现自选品系仅有TaLox-B1b与杂合型两种基因型,其中基因型TaLox-B1ab有32个,比例为60.4%。采用分子标记辅助选择,有利于快速鉴定小麦籽粒LOX活性,加速LOX的遗传改良和新品种选育。 相似文献
2.
为了解决马铃薯致病疫霉侵染马铃薯导致其死亡,进而造成马铃薯单位种植产量低的问题。本文从拮抗菌入手,归纳分析细菌类拮抗菌中的主要拮抗菌中芽孢杆菌、假单胞菌和粘细菌对马铃薯致病疫霉的抑制作用。同时,在总结前人研究的基础上,笔者认为在拮抗菌应用方面,可以采用多对一的新型平板对峙筛菌模式来模拟复杂条件下拮抗菌的拮抗作用,以期得到稳定的拮抗菌;并指出应从定植能力和根际微生物影响方面对拮抗菌实际应用的可行性进行研究;此外,提出未来对拮抗菌抑制马铃薯致病疫霉的探究应从表型层面的研究深入到分子层面,以期能成功从源头找寻抑制马铃薯致病疫霉的答案。 相似文献
3.
4.
为探讨模拟气候变暖(增温2℃)和大气氮沉降(4 g·m-2·a-1)对入侵植物子代生长的影响,以中国和北美两种来源的加拿大一枝黄花子一代为研究对象,研究了子一代幼苗的生长和生物量分配的响应.结果表明:(1)增温降低中国来源加拿大一枝黄花的地上生物量,但提高其根冠比,增温降低北美来源加拿大一枝黄花的根冠比;(2)与北美来源加拿大一枝黄花相比,加氮对中国来源加拿大一枝黄花叶片数、地下生物量和总生物量的促进作用更大;(3)加氮促进加拿大一枝黄花地上生物量、地下生物量和总生物量的积累,但增温减缓了这种促进作用.这些结果表明,气候变暖可能会部分抵消氮沉降对加拿大一枝黄花子一代幼苗生长的促进作用. 相似文献
5.
为了丰富紫花槭转录组数据,进一步开展紫花槭秋季叶片呈色机制研究.本研究以紫花槭秋季转色期三个阶段(前期,中期,后期)叶片为材料,采用高通量测序技术进行转录组初步分析.转录组数据共获得50501条Unigene,有35316条Unigene在数据库中得到注释,其中NR数据库中注释到的Unigene数量最多,共35024条,占69.4%.在注释到的物种中,紫花槭比对的Unigene与甜橙(Citrus sinensis)相似度最高,共有4290条,占12.25%.紫花槭转录组中的Unigene根据GO功能可分为生物学过程、细胞组分和分子功能3大类,共有25375条,其中生物学过程的基因最多,主要聚集于代谢过程和细胞过程等.基于Unigene库的基因结构分析,其中SSR分析共获得12711个SSR标记,占Unigene总数的36%.SSR位点共包含150种重复基元,单碱基重复所占比例最高(7184个,61.86%),四碱基重复、五碱基重复和六碱基重复所占比例较低.Unigene库中共有328239个SNP位点,发生频率为1/190 bp,SNP位点分为转换和颠换两种类型的碱基替换方式,其中碱基转换位点213787个(65.13%),碱基颠换位点114452个(34.87%),碱基转换类型发生频率高于颠换类型.6种单碱基变异中,2种转换类型A/G、C/T的发生频率分别为33.03%和32.10%;4种颠换类型中A/T发生频率最高,为11.52%;C/G发生频率最低,为5.79%.紫花槭转录组秋季叶色表达的转录组分析,可为紫花槭叶色基因调控、定向分子育种和培育彩叶新品种提供研究提供基础的数据信息. 相似文献
6.
Soil protection for a sustainable future: options for a soil monitoring network for Ireland
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The increased recognition of the importance of soil is reflected in the UN Post‐2015 Development Agenda with sustainable development goals that directly and indirectly relate to soil quality and protection. Despite a lack of legally binding legislation for soil protection, the European Commission remains committed to the objective of soil protection. However, the achievement of a legally binding framework for soil protection relies on the implementation of a soil monitoring network (SMN) that can detect changes to soil quality over time. As beneficiaries do not pay for the provision of soil information, the options for soil monitoring are limited. The use of existing data sets should be considered first. Using Ireland as an example, this research explored the opportunities for a SMN for Ireland considering three existing national data sets. The options for a SMN are considered in terms of their spatial and stratified distribution, the parameters to be measured and an economic analysis of the options proposed. This research finds that for Ireland, either a 10 or a 16 km2 grid interval stratified by land use and drainage class offers the best potential in relation to the spatial distribution of existing data sets to reflect local data at a national level. With existing data, the stratified SIS data using the 16 km2 grid offers the best value for money, with baseline costs for analysis, excluding field costs, of between €706 481 and €2.8 million. Acknowledging the impossibility of measuring all parameters with ideal frequency, this study proposes a two‐tier system for optimized monitoring frequency. Parameters must anticipate future policy requirements. Finally, the implementation of a SMN must be accompanied by standardized methods, defined thresholds and action mandates to maintain soil quality within allowable limits. 相似文献
7.
In a feeding trial lasting for months Halothane-positive fattening pigs were put on a diet containing different concentrations of vitamin E and selenium. After a Myostress application vitamin E and selenium were additionally injected in order to examine stress resistance (CK-test) and regenerative capacity (histological examination of Musculus longissimus dorsi) of skeletal muscle. The study revealed that neither high dietary levels of vitamin E/selenium nor a vitamin E/selenium treatment applied after stress are capable of preventing stress related myopathy nor can they influence its healing up favourably. 相似文献
8.
Differences in gas exchange parameters i.e. carbon exchange rate (CER), transpiration (Tr), water vapor conductance (g) were investigated, under a controlled environment, in a semi-dwarf (SD) Triticum aestivum line, its tall (TL) near isoline and the Payne (PA) variety characterized by small leaves. The plants were maintained in: (a) optimal substrate moisture condition (CTR); (b) salinized by watering with a 0.12 m NaCl solution (SLT); (c) water stressed by withholding waterings during a period of six days (STR); (d) stressed and salinized during the same period and with the same saline solution (S + S). CER and Tr were negatively affected by the stresses; SLT and S + S treatments had a higher WUE compared to their respective controls CTR and STR.
SD line had a better performance in terms of CER and WUE, particularly when water and salt stresses interacted. Leaf anatomy and assimilation/internal CO2 concentration curves contributed to explaining the SD performance. 相似文献
SD line had a better performance in terms of CER and WUE, particularly when water and salt stresses interacted. Leaf anatomy and assimilation/internal CO
9.
Pilot study of the effect of acemannan in cats infected with feline immunodeficiency virus. 总被引:7,自引:0,他引:7
K M Yates L J Rosenberg C K Harris D C Bronstad G K King G A Biehle B Walker C R Ford J E Hall I R Tizard 《Veterinary immunology and immunopathology》1992,35(1-2):177-189
Acemannan, a complex carbohydrate shown to stimulate interleukin-1, tumor necrosis factor alpha and prostaglandin E2 production by macrophages, has also demonstrated antiviral activity in vitro against human immunodeficiency virus, Newcastle disease virus and influenza virus. A pilot study was undertaken to determine acemannan's effect in 49 feline immunodeficiency virus (FIV) infected cats with clinical signs of disease (Stage 3, 4 or 5), 23 of which had severe lymphopenia. Cats received acemannan either by intravenous (Group 1) or subcutaneous (Group 2) injection once weekly for 12 weeks, or by daily oral (Group 3) administration for 12 weeks. Upon entry into the study, cats were randomly assigned to one of the three groups. Laboratory analyses were performed at the beginning of the study and at Weeks 6 and 12. Cats were allowed to continue with a predetermined maintenance regimen of acemannan after completing the 12-week study. Thirteen cats died during the course of treatment. Upon necropsy, the most frequent histopathologic findings were neoplastic, kidney and pancreatic disease. Friedman's two-way ANOVA test showed no significant differences in efficacy among groups administered acemannan by the different routes. Therefore, groups were combined and a signed-ranks test was used to determine changes over time. A significant increase was seen in lymphocyte counts (P < 0.001). Neutrophil counts decreased significantly (P = 0.007), as did incidence of sepsis (P = 0.008). When cats entering with lymphopenia were analyzed separately, a much greater increase in lymphocyte counts was noted (235%) compared with non-lymphopenic cats (42%). A survival rate of 75% was found for all three groups. Thirty-six of 49 animals are alive 5-19 months post-entry. These results suggest that acemannan therapy may be of significant benefit in FIV-infected cats exhibiting clinical signs of disease. 相似文献
10.
Abstract. A humoral antibody response was demonstrated by ELISA in rainbow trout immunized intraperitoneally with extracts from the branchiuran ectoparasite Argulus foliaceus. A similar immunization protocol produced a higher titre response in a rabbit. Both trout and rabbit identified several antigenic components on immunoblots. ELISA and immunoblotting indicated that rainbow trout and rabbit anti-A. foliaceus sera identified components from the parasitic copepods Lepeophtheirus salmonis and Caligus elongatus. 相似文献