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1.
为探讨大白菜基因组序列中SSR位点的分布规律并开发SSR引物,利用SSRHunter软件对大白菜A10(16899818~17299817)的DNA序列进行简单序列重复(SSR)位点查找,共得到394个SSRs,平均每1.02kb出现1个SSR。二核苷酸和三核苷酸重复是最主要的SSR类型,分别占79.44%和18.78%。为了提高SSR标记开发的准确性和通用性,对检索得到的含SSR位点的序列进行了同源比对,选取符合条件的15条SSR序列并设计引物;依据Blast过程中发现的在SSR位点不存在差异而在其侧翼序列中存在插入/缺失(InDel)差异的序列,设计了19条InDel引物。用34对SSR及InDel引物在6个大白菜(Brassica rapassp.pekinesis)材料中进行多态性研究,发现28对引物能扩增出理想的PCR产物,有效扩增率为82.35%,其中27对引物具有多态性,多态性比率为79.41%。为验证SSR引物的真实性,随机对4对SSR引物的部分白菜扩增片段进行了测序,发现100%的片段具有相应的SSR位点。28对SSR和InDel引物在甘蓝(B.oleracea)、油菜(B.napus)和萝卜(Raphanus sativus)品种的有效扩增率分别为85.71%、100%和77.78%,说明新开发的SSR和InDel标记具有较好的多态性和通用性。利用6对引物分析了48份十字花科种质的遗传多样性,结果表明48份材料被明显地区分成白菜和甘蓝组、萝卜组、油菜组3大类群,与传统分类一致。大白菜SSR和InDel标记的开发对于十字花科种质亲缘关系及遗传多样性分析具有重要的应用价值。  相似文献   

2.
为了开发铁皮石斛EST-SSR分子标记,利用SSRIT软件对铁皮石斛近缘物种-金钗石斛的15 383条EST序列进行SSR位点查找,利用Primer 5和Oligo 7软件进行引物设计和评价,之后经PCR扩增和琼脂糖凝胶电泳对引物进行初步筛选,并通过聚丙烯酰氨凝胶电泳对所筛选的引物进行有效性检测。结果表明,SSRIT软件共查找到370条SSR位点序列,共有379个SSR位点,候选SSR位点出现的频率为2.46%。二核苷酸、三核苷酸和六核苷酸重复是最主要的重复类型,分别占41.42%、26.91%和27.44%,其中二核苷酸重复中AG/CT(20.84%)和GA/TC(18.73%)最丰富;三核苷酸重复中TCT/AGA(4.22%)和GA/TC(3.96%)最丰富;而六核苷酸重复基元较多。EST-SSR平均长度为24 bp,平均每8.5条EST序列包含1个SSR位点。设计的106对EST-SSR引物中有50对能扩增出理想的PCR产物,引物有效扩增率为47.17%,其中有43对能够扩增出多态性条带,占可扩增引物的86%。本研究开发的43对引物为铁皮石斛遗传多样性分析、种质鉴定、遗传图谱构建和功能基因研究等提供了重要的参考价值。  相似文献   

3.
为开发石蒜属简单重复序列(SSR)分子标记,并研究SSR引物在石蒜属内的通用性,本研究对石蒜属石蒜、忽地笑、中国石蒜、长筒石蒜、换锦花、香石蒜6个种质转录组测序,检测SSR位点并设计引物,通过PCR扩增和毛细管电泳判断引物的有效性和多态性,绘制石蒜属17个种质资源的指纹图谱并对杂交后代的真实性进行早期检测。结果表明,共获得404 481条Unigenes,利用数据库进行同源比对和功能注释,并对Unigene进行SSR位点挖掘和分析,共检测到59 612个SSR位点。其中,单核苷酸重复>二核苷酸重复>三核苷酸重复,分别占SSR总数的62.88%、20.06%和14.66%,四核苷酸及以上重复单元相对较少。选取并合成8对荧光引物进行PCR扩增,通过毛细管电泳检测发现,8对荧光引物共检测到60个多态位点,多态位点数平均为7.50,多态性信息含量(PIC)值变化范围为0.148 0~0.940 8,平均值为0.593 0。利用引物扩增带型组合法构建了石蒜属17个种资源的指纹图谱,其中引物QZ209可区分所有供试材料,并可用于杂交后代鉴定。本研究开发的SSR标记具有丰富的多态性,在石蒜属植物的资源多样性分析、杂交种鉴定及遗传图谱的构建应用中具有重要意义。  相似文献   

4.
竹类植物EST-SSRs分布特征及应用   总被引:2,自引:0,他引:2  
本研究利用毛竹已有的EST序列,开发竹类植物EST-SSR标记,旨在对竹子的分子分类进行研究。通过对3087条毛竹(Phyllostachys pubescens)EST序列进行筛选,获得了408条含有SSR的毛竹EST,在所有的EST-SSR中,三核苷酸重复类型(49.75%)最多,其次是二核苷酸重复类型(43.14%)、五核苷酸重复类型(4.41%)、四核苷酸重复类型(1.72%)和六核苷酸重复类型(0.98%)。不同基序类型中,GAG/CTC基序和AG基序分别是三核苷酸重复类型和二核苷酸重复类型中含量最高的重复基序,分别占18.72%和71.02%。当SSR长度等于18bp时,所检测到的SSR数量最多,达140条。随着SSR长度的增加,所检测到的SSR数量呈下降的趋势。根据搜索出的EST序列,共设计出25对引物,对12个竹类植物进行了扩增效率、多态性及通用性检测。其中18对引物能够扩增出稳定且清晰的条带,16对引物扩增具有多态性,扩增片段长度主要集中在100~500bp,引物有效率达64%。依据扩增结果进行遗传相似性分析,12种竹类植物可分为两大类群:丛生竹类群(clump bamboos)和散生竹类群...  相似文献   

5.
为开发菊花EST-SSR标记并用于万春菊资源分析,研究了菊花的EST-SSR特征、标记开发及其在万寿菊上的可转移性。结果表明,菊花EST-SSR出现频率为5.35%,平均每10.64 kb存在1个SSR位点。在这些SSR位点中,共有83种重复基元,2-6核苷酸重复类型分别为10、40、14、5和14种。以14个菊花品种DNA为模板,22对菊花EST-SSR引物中14对可以扩增到清晰且稳定的PCR产物,共检出49个位点,平均每对引物可扩增出3.5条多态性片段,平均多态性信息含量(PIC)为0.751。在14对有效引物中,8对可以在待检万寿菊样品中扩增到清晰稳定的条带,可转移率为57.14%。综上所述,菊花以三核苷酸重复类型占主导,六核苷酸重复类型高于其它植物种类,菊花EST-SSR引物多态性信息含量处于较高水平。本研究可为万寿菊分子标记辅助育种奠定科学基础。  相似文献   

6.
大白菜表达序列标签SSR标记分析*   总被引:18,自引:2,他引:18  
对大白菜(Brassica campestris L.ssppekinensis)13007个EST序列进行拼接共得到7714个片段重叠群(contig),其中10.4%(890个)非冗余EST含有SSR标记(EST-SSR),标记间平均间隔距离为3.9kb,单、双和三核苷酸重复序列大约各占1/3左右。CDS所包含的三核苷酸重复序列最多,而且AAG/CTT重复序列的含量最高。通过同源性比较分析,获得功能已知的SSR-ESTs774个,共计含有846个SSR,其中50.2%位于5'-UTR,31.4%位于3'-UTR,18.4%位于CDS。实验选取123个SSR座位设计引物,利用芜菁花叶病毒(Turnip mosaic virus,TuMV)的高抗和高感大白菜F6代自交系材料各2份,分析EST-SSR标记多态性。结果表明,其中37个标记可进行有效扩增,但是没有表现出多态性,23个标记(18.7%)至少在1份材料中具有多态性。对这些EST-SSR标记在大白菜和其它芸薹属植物的系统发育关系分析、遗传作图和基因定位的应用进行了讨论。  相似文献   

7.
为了解人参属植物EST中SSR分布特点及其在三七SSR标记中的应用,利用生物信息学方法,用primer3软件对dbEST数据库中人参属植物人参、西洋参和三七的EST序列进行搜索,发现人参属植物EST-SSR出现频率为11.54%,平均每4.39kb出现1个SSR。人参属植物单核苷酸重复基元占主导地位,其次为三核苷酸重复基元和二核苷酸重复基元,分别占总SSR的54.48%、17.31%和16.36%。人参属EST-SSR的优势类型为A/T和AT/TA,分别占54.73%和8.21%。根据人参属植物EST中的SSR设计48对引物,在合适的PCR扩增体系下,用5个三七样品的DNA为模板进行PCR扩增,引物有效扩增率85.42%,其中多态性引物占可扩增引物的70.73%。结果表明,利用人参属EST序列开发三七EST-SSR标记是可行的。  相似文献   

8.
换锦花EST-SSR标记开发及遗传多样性分析   总被引:2,自引:0,他引:2  
为开发换锦花EST-SSR标记和分析其遗传多样性,本研究利用MISA软件对换锦花转录组信息进行SSR位点检测,再利用Primer3.0设计引物,经PCR扩增和非变性聚丙烯酰胺凝胶电泳检测引物的有效性和多态性,并绘制换锦花种质资源的聚类图。结果表明,共检测到9 918个SSR位点,发生频率为18.59%,分布距离为3.729 kb;SSR位点重复单元为1~3个碱基,其中,单碱基重复三碱基重复二碱基重复,分别占SSR总数的61.08%、23.22%和14.23%,四碱基及以上重复单元相对较少。共设计出9 302对SSR引物,随机选取并合成278对引物进行PCR扩增,能够清晰扩增出的引物有185对(66.55%),在石蒜属的七个种中具有多态性的有59对(31.89%),其中11对(18.64%)能够在浙江和江苏种群的30份换锦花种质资源表现出丰富的多态性。综上,本研究开发的EST-SSR标记具有丰富的多态性,在换锦花以及石蒜属植物的遗传多样性分析、杂交种鉴定及遗传图谱的构建应用中具有重要意义。  相似文献   

9.
菠菜转录组SSR位点分析及其分子标记的开发   总被引:1,自引:0,他引:1  
简单重复序列(simple sequence repeat,SSR)分子标记具有多态性高、重复性好、共显性等特点,己广泛用于蔬菜作物遗传育种研究中.本研究利用MISA软件对菠菜(Spinacia oleracea)转录组SSR位点信息进行分析,开发适用于菠菜的SSR分子标记,并对不同菠菜材料的遗传多样性进行分析.结果显示,在获得的44 796条基因簇(Unigene)中检测出2 045个SSR位点,检测出2 045个SSR位点,分布在1 940条Unigene上,发生频率为4.33%,平均距离为19.81 kb.菠菜SSR中以单、三、四核苷酸重复为主,分别占总SSR的19%、65%和7%,重复长度主要为18~24 bp,占菠菜总SSR的93.55%,以重复次数6次和7次为主,分别占菠菜总SSR的31.42%和31.05%.菠菜转录组中单核苷酸重复类型为A/T,二核苷酸重复主要为GA/TC和AG/CT,三核苷酸重复主要以CAA/TTG、GTT/AAC、GAA/TTC、TGT/ACA和GAT/ATC为主.本研究共设计了2 199对SSR特异位点引物,随机挑选218对引物对9个不同类型的菠菜材料进行扩增检测,其中38对表现出多态性.利用UPGMA做图进行聚类分析,9份菠菜材料聚为3类.本研究通过对菠菜转录组SSR位点信息分析及其分子标记的开发,获得了多态性较为丰富的SSR位点,为菠菜遗传多样性的分析、遗传图谱的构建及分子标记辅助育种提供了基础资料.  相似文献   

10.
与大白菜TuMV抗病基因TuRBCS01紧密连锁的分子标记开发   总被引:1,自引:0,他引:1  
分子标记辅助选择可大大加快育种进程,然而由于大白菜抗病毒病遗传规律的复杂性,目前所定位的基因和筛选的连锁标记远不能满足育种需要,为了更好地对抗病毒病白菜(Brassica campestris ssp.pekinensis)进行分子标记辅助选择,本研究筛选了与大白菜抗芜菁花叶病毒(Turnip mosaic virus,TuMV)抗性基因TuRBCS01紧密连锁的分子标记.本研究在对该基因进行定位的基础上,利用回交1代(backcross1,BC1)分离群体,采用分离群体分组分析法(bulked segregation analysis,BSA)、简单重复序列(simple sequence repeats,SSR)和序列特异引物(sequence specific primer,SSP)标记技术,筛选与该基因紧密连锁的分子标记.通过对13对SSP引物和16对SSR引物的分析表明,有8对引物在两亲本间表现多态性,有5对引物扩增出的标记与基因TuRBCS01紧密连锁或共分离,分别为mBr4072、Bra025493-1、Bra025493-2、Bra025467-4和Bra025467-5.筛选出与大白菜TuMV抗性基因TuRBCS01紧密连锁的分子标记2个,分别为SAAS_mBr4072_240 (1.5 cM)和Bra025493-1(1.0 cM),另有3个标记与基因TuRBCS01共分离,分别为SAAS—Bra025493-2_749、SAAS_ Bra025467-4—780和SAAS—Bra025467-5_ 956.上述标记丰富了大白菜抗TuMV分子标记的数量和种类,有望用于大白菜抗病毒病分子标记辅助选择.  相似文献   

11.
Aluminum (Al) toxicity represents one of the main yield-limiting factors for crops in acid soils. Silicon (Si) is known to increase tolerance in higher plants. This study was conducted to determine whether treatment with Si could improve nutrient uptake by peanut under Al stress. Peanut (Arachis hypogaea L. cv Zhonghua 4) was raised with or without Si (1.5 mM) in the growth chamber under 0 and toxic Al (0.3 mM) levels. Aluminum stress significantly decreased the root- and total-dry weight by 52.4% and 32.0%, respectively. The content of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) was significantly decreased, but that of Al increased markedly in shoots and roots after Al exposure at seedling, flower-needle, and pod-setting stage. Silicon alleviates Al toxicity in peanut plants in relation to Al distribution and allocation of tissue P, K, Ca, and Mg by favoring the partitioning of dry mass to roots.  相似文献   

12.
Inductively coupled plasma-mass spectroscopic (ICP-MS) analysis of leaves from 22 cabbage crops in the Sa P? and B?c Hà districts of Láo Cai Province, North-Western Vi?t Nam, revealed unexpectedly high concentrations of chromium (Cr) and nickel (Ni). The concentrations were strongly linearly related (r2 = 0.94), indicating sample contamination during grinding through a stainless-steel hammer mill. We tested this hypothesis in two ways. First, brown rice ground through the same mill was contaminated not only by Cr and Ni, but also cobalt (Co), iron (Fe) and molybdenum (Mo). Second, scanning electron microscopy/energy dispersive analysis of x-rays (SEM/EDS) of the ground samples revealed small fragments with co-located Fe, Cr and Ni, consistent with stainless steel wear fragments. Other grinders may perform differently and we suggest that quality assurance protocols for trace metal analysis of plants should include testing for grinder wear metals. Lastly, brown rice appears to be convenient for investigating contamination of plant tissues during grinding.  相似文献   

13.
模拟降雨条件下污染土壤中重金属元素径流迁移特征   总被引:6,自引:0,他引:6  
探明污染土壤中重金属元素随地表径流迁移特征,对于防控重金属污染物的迁移扩散具有重要意义。通过室内模拟降雨试验,研究不同降雨强度下(55,100,120mm/h)污染土壤中Cd、Pb和Cr随地表径流迁移的特征。结果表明:径流中3种重金属元素总量在产流的前20min内逐渐降低,随后趋于稳定;产流初期(产流10min内)颗粒态重金属占径流重金属总量的比例均在80%以上;随产流时间延长,颗粒态Cd和Cr对径流重金属的贡献率快速降低,其颗粒态/溶解态的比值范围分别为47.0~0.4和12.9~0.4,而Pb则主要以颗粒态的形式存在,溶解态Pb对其随径流迁移的贡献率可忽略不计;随降雨强度增大,径流中总Cd和Pb含量显著降低,而径流中总Cr含量以及溶解态重金属含量无明显变化规律。  相似文献   

14.
Information is scant on the effect of humic acid (HA) on physiological, antioxidant and photosynthesis attributes of gerbera plants undergoing nutrient deficiency in culture solution. Gerbera plants cv. Malibu were grown in a factorial experiment based on a completely randomized design with 3 replications, using 3 different nutrient solutions [complete nutrient solution (NSc), 25% NSc (NS1), and 50% NSc (NS2)] treated with 2 levels of humic acid [0 (HA0) and 500 mg/l (HA1)].The interaction effect of HA and NS showed that HA improved the flower number in NSc, the transpiration in NS1+HA1, photosynthesis rate in NSc+HA1, stomatal conductance (gs) in NS2, mesophyll conductance of leaves in all NS levels and photosynthetic water use efficiency in NSc+HA1. The interaction effect of nutrient solution and HA on antioxidant activity was inconclusive, malondialdehyde content was the highest in NS2 and the lowest in NS1+HA1. The peroxidase activity increased in complete nutrient solution with and without HA and there were no differences among other treatments. Superoxide dismutase activity increased in NS1 and complete nutrient solution with HA and reached the highest in NSc. Humic acid was more effective in nutrient uptake, i.e., nitrogen, phosphorus, potassium, calcium, zinc, and iron (N, P, K, Ca, Zn, and Fe) in complete nutrient solution compared to NS1 and NS2. Conclusively, humic acid can compensate the nutrient deficiency stress of the culture solution in regards to protein synthesis, photosynthesis attributes regardless of the nutrient uptake of gerbera.  相似文献   

15.
ABSTRACT

Delayed sowing and imprecise application of irrigation water to cotton has been the major hurdle in sustaining cotton yield in north-western India. Therefore, studies were initiated to ascertain the impact of heavy or normal level of presowing irrigation (PSI), scheduling time of first postsowing irrigation (POSI) under two sowing dates (SDs) on cotton arranged in a split block design replicated thrice. PSIh (100 mm) recorded 23.2% higher seed cotton yield over PSIn (70 mm) owing to better yield attributes and higher stand. First POSI at 4 weeks after sowing (WAS) resulted the highest yield (3072 kg ha?1), while one at 6 WAS (POSI6) recorded least due to poor population and reduced yield attributes. Water productivity under POSI6 was lesser by 29.1%, 25.2%, and 16.2% as compared to POSI3, POSI4, and POSI5, respectively. April sown crop out yielded the May sown cotton crop by 939 kg ha?1 due to better yield attributes. Nitrogen factor productivity (NFP) among SD remained higher by 23.3% for April as compared to May sowing. PSIh exhibited better NFP over PSIn. POSI6 recorded least NFP by 24.4%, 28.5%, and 16.3% as compared to POSI3, POSI4, and POSI5, respectively and was indicative of relatively poor utilization of N under delayed schedules. Therefore, planting in April after heavy PSI and scheduling first POSI at 4 WAS is best strategy for sustaining cotton yield and maximizing farmer profitability.  相似文献   

16.
采用田间小区试验研究“推荐配比”(N:P2O5:K2O比率为190:90:100 kg hm-2)、“高氮量配比”(N:P2O5:K2O比率为210:90:100 kg hm-2)、“低氮量配比”(N:P2O5:K2O比率为170:90:100 kg hm-2)以及“常规配比”(N:P2O5:K2O比率为216:112.5:202.5 kg hm-2)4种氮、磷、钾配比施肥对饲用稻威优198蔗糖合成酶(SUS)、腺苷二磷酸焦磷酸化酶(AGPase)、硝酸还原酶(NR)、谷氨酰胺合成酶(GS)以及产量和糙米蛋白质的影响。结果表明:“推荐配比”能提高不同生育时期水稻功能叶(旗叶)和粒籽中碳、氮代谢关键酶的活性,这些关键酶活性的变化显著影响水稻产量和糙米全氮以及蛋白氮的含量。统计(P0.05)结果证实“推荐配比”能提高水稻产量达到8200 kg hm-2,与“常规配比”相比产量提高了24.81%;“推荐配比”糙米全氮和蛋白氮含量分别达到22.70 g kg-1和21.98 g kg-1,与“常规配比”相比差异显著,并且其全氮和蛋白氮含量分别提高17.01%,18.38%。  相似文献   

17.
ABSTRACT

High bicarbonate (HCO3 ?) of irrigation water can be detrimental to plant growth in sustainable horticultural production systems. The ability of arbuscular mycorrhizal fungi (AMF), ZAC-19, (composed of Glomus albidum, Glomus claroideum, and Glomus diaphanum) to enhance tolerance to HCO3 ? was tested on Rosa multiflora cv. Burr. Arbuscular mycorrhizal colonized and non-inoculated (non-AMF) plants were treated with 0, 2.5, 5, and 10 mM HCO3 ?. Increasing HCO3 ? concentration and associated high pH and electrical conductivity (EC)—reduced plant growth, nutrient uptake, and acid phosphatase activity, while increasing alkaline phosphatase activity (ALP). Inoculation with AMF enhanced plant tolerance to HCO3 ?, as indicated by greater growth (leaf, stem, and total plant dry weight, leaf area and leaf area ratio), leaf elemental concentration [nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), iron (Fe), zinc (Zn), aluminum (Al), boron (B)], leaf chlorophyll concentration, higher mycorrhizal inoculation effect, lower root Fe reductase activity, and generally lower soluble ALP activity. While AMF colonization was reduced by increasing HCO3 ? concentration, colonization still occurred at high HCO3 ? concentration. At 2.5 mM HCO3 ?, AMF plant growth was comparable to plants at 0 mM HCO3 ?, further indicating the beneficial effect of AMF for alleviation of HCO3 ? plant stress.  相似文献   

18.
四种常规方法提取伊利石有效钾的机制比较   总被引:1,自引:0,他引:1  
采用化学分析、X射线衍射、中红外光声光谱以及原子力显微镜的方法,比较了0.2 mol L~(-1)四苯硼钠法、1 mol L~(-1)沸硝酸法、2 mol L~(-1)冷硝酸法和2 mol L~(-1)热盐酸法浸提伊利石中有效钾的机制。结果表明,四苯硼钠法浸提时,伊利石中钾素释放量达到全钾量的59.5%,且基本均通过层间交换反应予以释放,结构离子铁、铝和硅释放量极低;采用三种酸溶液浸提时,其钾素释放量仅占全钾量的1.53%~2.46%,通过层间交换反应释放的钾量占释放量的比例为88.4%~94.0%。四苯硼钠浸提时伊利石层间距扩大,产生次生过渡矿物,并形成富硅表层,但在伊利石表面无溶蚀特征;三种酸溶液浸提时伊利石结构无改变,但其结晶度降低,且表面有明显的溶蚀特征。因此,土壤矿物层间钾是作物可利用有效钾的主要来源,三种酸溶液浸提方法一方面低估了有效钾容量,另一方面提取了一部分不能为植物所利用的结构态钾,不适宜于用来评价伊利石及土壤有效钾库容量。  相似文献   

19.
ABSTRACT

Understanding the potential of clinoptilolite (CLI) for adsorption of NH4+ and K+, providing appropriate fertilizer formula, and evaluation of the produced zeolitic nutrient sources (ZNSs) to meet the plant need are the main objectives of this study. Three ZNSs (NH4+-saturated, K+-saturated and dual-purpose NH4+-K+ saturated CLI) were produced, assessed, and compared with commercial N and K fertilizers (CFs) on corn growth in a greenhouse. The results indicated that CLI can potentially adsorb both NH4+ and K+ to the maximum values of 25.00 mg-NH4+ g?1 and 47.61 mg-K g?1, respectively, and chemisorptions mainly followed the process of adsorption. Saturation of zeolite by NH4+ and K+ occurred after 10 and 15 d which lead to ZNSs with 2% and 5% of N and K, respectively. NH4+-K+ saturated CLI contained 1% N and 1% K. The greenhouse experiment showed no significant difference between ZNSs and CFs on plant growth. However, the application of both N and K in the form of zeolitic sources significantly increased the uptake of N by the plant. The highest uptake of K (2.05 g pot?1) occurred in plants supplied with both natural zeolite and CFs. The present results may benefit the future utilization of ZNSs in environmental friendly farming practices.  相似文献   

20.
本文报道了~125I(~131I)抗肿瘤药物氨甲喋呤的制备方法,用直接碘化法——NBS、ChT、Iodogen进行标记,并对这几种方法进行了比较。结果表明,NBS法最好,标记率达90—99%。经Sephadex G-75柱凝胶过滤后得到纯产品,放化纯度为95.4%。所制得的标记产品适用于示踪研究。  相似文献   

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