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1.
观赏水草是水族箱的重要组成部分,其消费日渐成熟。淘宝在售的观赏水草有淡水观赏水草17科22属96种(含品种),海水观赏水草10科11属13种。其中,淡水观赏水草有20种只具有观赏用途,占总种数的20.83%;76种兼具稳定水质和观赏用途,占总种数的79.17%。海水观赏水草有3种只具有观赏用途,2种兼具观赏和净化水质的用途,8种具有观赏、净化水质和饲用3种用途。淡水种类绝大部分都是外来种,仅13种在中国有分布,仅占总种数的13.54%;海水种类由于海水传播的特殊性,均为全球广布种或东太平洋种类。  相似文献   

2.
Properties of natural fibers are influenced by the nature of their surface. Oil Red was evaluated as a histochemical stain for the waxy components on the surface of cotton and flax fibers and of plant cuticles. A positive reaction for arachidyl stearate and differential staining of fibers after sequential extraction of fatty acids and alcohols indicated that Oil Red stained wax components in plant materials. For cotton (Gossypium hirsutum) fibers, Oil Red stained to a greater extent the regions closest to the seed coat, especially at points where fibers attached to the seed coat. Fiber regions at a distance from the seed coats stained irregularly, suggesting that the wax was unevenly distributed. Flax (Linum usitatissimum) bast fibers, in contrast, did not stain with Oil Red, but the protective stem cuticle was intensely stained. The positive histochemical reaction for cuticle identified non-fiber fragments in processed and cleaned flax fibers, thus providing a quick method to detect visually trash components in fiber and products. Likewise, bast fibers from kenaf (Hibiscus cannabinus) did not stain well with Oil Red, whereas the stem cuticle gave a positive reaction. The general usefulness of Oil Red as a histochemical stain for the plant cuticle was demonstrated in leaves and stems of mature corn (Zea mays) and fresh bermudagrass (Cynodon dactylon) leaves. Oil Red provides a quick, qualitative histochemical method to demonstrate the wax-containing cuticle in plants.  相似文献   

3.
水稻中花11辐射突变体的分离与鉴定   总被引:9,自引:1,他引:9  
利用伽玛射线对粳稻品种中花11进行辐照,以诱导广泛的形态突变体,为水稻功能基因组研究提供基础材料。辐射第1代单本移栽并实行单株收获;辐射第2代(M2)播种1万个家系,自苗期开始至成熟期各个生育阶段从中独立选获各类形态突变体540个;经M3复选获得包括叶、茎、穗和育性变化等各类突变体431份。统计结果表明,形态性状的突变频率为5.1%。关键词  相似文献   

4.
5.
玉米幼苗叶表面蜡质含量及成分对干旱胁迫的响应   总被引:1,自引:1,他引:0  
选用抗旱性不同的两个玉米自交系Mo17和B73为试验材料,采用盆栽控水试验,设置干旱和正常浇水两个处理,研究干旱胁迫对两个玉米品种3叶期幼苗叶面蜡质含量及成分变化的影响。结果表明,在干旱处理条件下,Mo17和B73的叶片失水率和叶绿素的抽提率均低于正常条件;两个品种叶面的蜡质含量均明显高于正常条件下的蜡质含量,且Mo17在正常和干旱条件下蜡质含量均高于B73。此外,在干旱条件下,蜡质合成相关的基因KCS、CER1、CER2、GL1、GL2和GL15的表达也明显增高。玉米叶片表面蜡质合成是应答干旱胁迫的一种重要方式,抗旱品种Mo17的抗旱性比B73要强,其表面蜡质合成较强是其中一个重要原因。  相似文献   

6.
【目的】研究两个水稻垩白突变体胚乳垩白的形成机制,为稻米品质改良提供理论基础。【方法】以从中花11的EMS突变体库中筛选出的两个稳定遗传的垩白突变体eb6、eb7为材料,对其进行农艺性状、稻米理化性质和遗传学分析,并利用eb6与南京11衍生的F2群体对控制垩白的基因进行图位克隆。同时对候选基因的表达模式及淀粉合成相关基因在突变体及野生型中表达情况进行了分析。【结果】与野生型相比,两个突变体胚乳中央部位呈现白色且不透明,淀粉复合颗粒形状不规则且排列疏松,而突变体胚乳边缘部位与野生型无异,都为半透明状,淀粉复合颗粒呈多面体且排列致密。相对于野生型,突变体eb6、eb7成熟种子中的直链淀粉含量和胶稠度显著降低,蛋白质含量显著升高。RVA谱分析显示突变体淀粉黏滞性明显低于野生型。同时,支链淀粉聚合度分析显示突变体eb6中聚合度(DP)小于16的短链显著增加,DP为16~23的中长链显著减少。遗传分析表明突变体eb6、eb7胚乳垩白表型由单隐性核基因控制,并且它们为一对等位突变体。利用突变体eb6与南京11杂交衍生的F2群体将突变体基因定位在第1染色体长臂上物理距离86.6 kb的区间内。该区间包含22个开放阅读框(ORF),其中ORF13编码腺苷二磷酸葡萄糖焦磷酸化酶大亚基2(Os AGPL2)。序列分析发现eb6与eb7分别在Os AGPL2第3、第7外显子上发生1个单碱基替换,并分别导致一个氨基酸替换。RT-PCR及原位杂交结果显示,Os AGPL2主要在水稻发育中的籽粒中表达。同时Os AGPL2的突变导致了多个淀粉合成相关基因在水稻籽粒灌浆过程中的表达模式发生改变。【结论】突变体eb6、eb7籽粒胚乳出现严重垩白表型为Os AGPL2突变所致。本研究进一步证明了Os AGPL2在调控水稻籽粒胚乳中淀粉的合成、淀粉复合颗粒的形成及稻米理化性质的平衡中起着重要的作用。  相似文献   

7.
[目的]探究OsARF7基因在水稻生长发育中的生物学功能及其对水稻农艺性状的影响.[方法]利用CRISPR/Cas9技术,在粳稻中花11背景下对OsARF7进行定向编辑,获得OsARF7基因突变植株,并考查其农艺性状.[结果]获得22株T0代转基因株系,经PCR扩增潮霉素基因鉴定出20株阳性植株.提取T2代转基因植株的...  相似文献   

8.
《Field Crops Research》2006,96(1):19-24
The indeterminate growth habit of sesame (Sesamum indicum L.) causes non-uniform ripening of the capsules. As a solution to this problem, breeding for a determinate growth habit in sesame has become an active area of research after the discovery of dt-45, which was the first determinate mutant. The current study aimed to select new determinate mutants in locally adapted genetic backgrounds, and to describe their morphological characteristics and frequency. Consequently, the seeds of four sesame cultivars (Muganlı-57, Özberk-82, Çamdibi and Gölmarmara) were irradiated with doses of gamma rays (150-750 Gy) in two separate sets during 1994 and 1995, respectively, and the M1 populations were grown. The M2 populations were produced from the M1 progenies in both sets of experiments and also from the bulk population in the first set. Three true botanical determinate mutants (dt-1, dt-2 and dt-3) of Muganlı-57 and three short flowering period leafy determinates (dt-4, dt-5 and dt-6) of Çamdibi were selected in the M2 generations grown in Antalya, Turkey, in 1995 and 1996, respectively. Furthermore, these mutants were confirmed to breed true in the M3 and subsequent generations. Other cultivars did not yield any mutants of interest. The dt-1 mutant was similar to dt-45 and was free from the drastic changes caused by irradiation with 150 Gy. By contrast, the dt-2 and dt-3 mutants showed deformed multicarpellate capsules that were selected at the higher gamma-ray doses (300 and 400 Gy, respectively). The true botanical mutant character was recessive and monogenic, as revealed by the segregation of the M2 and M3 families. The mutation frequency for the true botanical determinates was 1.8 × 10−4 in both sets of cultivars and doses. The mutant frequency for the short flowering period mutants that were selected in the bulk population was 2.9 × 10−5. This study proved that the selection of unique mutants with a determinate growth habit is not a matter of chance; rather, it depends upon population size, the response of the cultivars to effective mutagenesis and careful screening.  相似文献   

9.
The cuticle of flax stems contains lipids that provide a protective barrier to pathogens and control moisture loss. These lipids include wax esters and long chain fatty alcohols or policosanols. Cuticle fragments generated during several different fiber processing operations retain these lipid compounds that represent a potential co-product. Samples of flax shives (i.e., lignified core tissues), processing dust, and cuticular fractions recovered from enzyme retting waste water were extracted on a laboratory scale with hot ethanol to remove the lipid compounds. Ethanol extracts were analyzed by gas chromatography to determine the amount and type of lipids recovered. The results demonstrated that hot ethanol effectively extracted the lipid compounds from cuticle fragments in all these samples. When the extract was cooled, the longer chain wax esters (i.e., chain length of 44 carbon atoms or larger) precipitated and could be separated from the shorter chain lipid components (i.e., fatty alcohols and aldehydes less than 44 carbons). Similar results were obtained using absolute ethanol or 95% ethanol (aqueous). This technique provides a very economical method to recover lipid fractions as potential value-added co-product from flax processing waste.  相似文献   

10.
Traditional healthy beverages in several African counties were home-made by water extraction of flowers of Delonix regia (Boj.) Raf. This tree belongs to the local biodiversity of plants used in the local medicine. It is also part of the traditional bioproducts marketed within African village communities. Scaling-up at pilot plant level, by mimicking this local recipe, lead to concentrated bioproducts containing various natural phenolic compounds, most of them have never been yet published. A three-steps process was used to prepare concentrated of water-extracted soluble phenolics. This process included: phenol extraction of dried plant by overnight diffusion in acidified water, clarification then concentration of the macerate, using membrane technology. Total phenol contents were determined as gallic acid equivalents using the Folin-Ciocalteu method. Total flavonoid contents, as delphinidin equivalents, were determined using the UV-vis colorimetric method. Comparison of concentration factors of both phenol families (phenolic acids and flavonols) contained in the 3 co-products obtained during the process were made between crude extracts, cross-flow microfiltration extracts and reverse osmosis concentrated extracts. Individual phenol compounds found in the products obtained were characterized and quantified by HPLC-DAD and by HPLC-MS2. Among the 11 phenol compounds identified in the water-extracts, 3 have been already identified in the literature (2 phenolic acids and 1 flavonol), and 8 new compounds, in noticeable amounts, have never been cited. We have confirmed the presence of phenolic acids such as 3,4,5-trihydroxybenzoic (gallic acid), 3,4-dihydroxybenzoic (protocatechuic acid) and of quercetin. We have characterized for the first time the presence of 2-hydroxy 5-[(3,4,5 trihydroxyphenyl) carbonyl oxy] benzoic acid and of 7 other flavonols belonging to the quercetin, kaempferol and isorhamnetol compound families. Using both LCMS and NMR analyses, they have been identified and quantified as: rutin, quercetin 3-O-glucoside, quercetin 3-O-galactoside, quercetin trihexoside, quercetin 3-O-robinobioside, kaempferol rhamnosylhexoside and isorhamnetol rhamnosyl-hexoside.  相似文献   

11.
Bagasse particleboards (BPBs) were made using polymeric methylene diphenyl diisocyanate (pMDI) resin as binder and wax emulsion as dimension stabilizer. A factorial experiment was conducted to measure the effects of wax and pMDI resin content on particleboard dimension stability and mechanical properties. The data were compared with respective properties specified in the ANSI A208.1 standard for commercial M3 grade wood-based particleboard.Wax-sizing improved the linear expansion (LE) of the particleboards under both pMDI resin contents used in this research and all LE values were controlled under the critical value of 0.35%. The use of wax significantly reduced 24-h water absorption and thickness swelling compared to the control panels without wax. Wax-sizing at the moderate levels also showed positive influence on long-term water absorption and thickness swelling properties. Wax content levels, however, did not significantly influence water absorption and thickness swelling behavior. Wax-sizing had no evident negative effects on the bending properties of MDI-bonded bagasse particleboards under both resin contents, while it caused slightly negative effect on internal bond strength. Mechanical properties of all boards far exceeded the minimum values specified in ANSI A208.1 standard. The entire properties of the 5% pMDI BPBs were better than those of the 3% pMDI panels as expected.  相似文献   

12.
选取5个与bin2.09主效抗病位点紧密连锁的分子标记,利用含主效抗病位点的黄早四近等基因系1JD006为供体亲本,开展连续回交分子标记辅助选择育种,定向改良玉米自交系昌7-2的丝黑穗病抗性。结果表明,标记3M1-25选择效率最高,其次为标记MZA6393。结合分子标记辅助选择和田间接种鉴定,在BC2F2群体中筛选出背景回复率大于理论值87.50%的6个单株,BC3F2世代中筛选出背景回复率大于理论值93.75%的12个单株,其中6株回复率≥96.92%,田间接种发病率均低于40%。筛选出的6个BC3F3家系中除4JZ574-01外在主要农艺性状上与轮回亲本无显著差异。  相似文献   

13.
A new methodology for the determination of β-glucan average molecular weights within the range 30-100k has been developed. It was found that, when the amount of β-glucan was determined by the Calcoflour flow-injection analysis (Calcoflour-FIA) method with two eluants, one of high ionic strength (0·02 g/l Calcoflour in aqueous 0·1 M Tris, pH 11, 0·17 M NaCl), which fully detects β-glucan of molecular weight (MW) higher than approximately 10k, and the other of very low ionic strength (0·02 g/l Calcoflour in aqueous 0·1 M Tris, pH 11), which fully detects only high MW (> 150k) β-glucan, the ratio of the amounts detected by the two eluants was correlated with the average molecular weight of β-glucan. When compared with the high-performance size-exclusion chromatography with post-column detection by Calcoflour-FIA (HPSEC-FIA) method, both methods gave similar results within the range of applicability of the new method.  相似文献   

14.
【目的】水稻花药角质层和蜡质层是花粉囊发育重要的结构支撑和安全屏障。对花粉囊发育相关基因进行表型分析和遗传定位,为进一步克隆相关基因和分子机制研究提供基因资源和理论基础。【方法】从籼稻中恢8015辐射诱变(~60Co-γ)突变体库中分离鉴定出了一个无花粉型雄性不育突变体whf41。对野生型和突变体不同发育时期的花药进行半薄切片观察;并对其成熟期的花药进行扫描电镜观察。将突变体分别与中恢8015和02428杂交,构建BC_1F_1、F_1株系和BC_1F_2、F_2群体,对该表型进行遗传分析,采用图位克隆的方法精细定位目的基因。【结果】表型分析结果显示,whf41突变体的花药瘦小且呈透明乳白色,花药中不包含花粉粒细胞;半薄切片结果显示,突变体的小孢子无法形成正常的花粉外壁,绒毡层细胞异常膨大而不进行程序性死亡,最终膨胀的绒毡层和花粉细胞碎片逐渐融合并充满药室;扫描电镜结果进一步发现突变体花药内外壁均呈平滑状而缺乏脂类物质,花粉细胞逐渐破碎并降解。遗传分析表明,whf41突变体的无花粉型雄性不育性状受一对隐性核基因控制,我们将该基因精细定位于第3染色体短臂XD-5和XD-11两个标记之间,物理距离45.6 kb,其中包含9个开放阅读框。序列分析显示该区间内细胞色素P450基因LOC_Os03g07250的第4个外显子处存在1个单碱基替换和3个碱基的缺失,导致其翻译序列发生一个氨基酸的替换(天冬氨酸→甲硫氨酸)和一个氨基酸(缬氨酸)的缺失,致使其功能改变进而出现该表型。q RT-PCR检测结果表明,whf41突变体中CYP704B2和一系列花药脂质合成与转运相关基因的表达水平均发生了显著下调。【结论】根据本研究结果可推断,Os WHF41是CYP704B2的新等位基因,相关结果进一步明确CYP704B2在水稻花药脂质合成与花粉壁形成过程中的重要作用。  相似文献   

15.
水稻叶穗色泽突变体为解析不同器官叶绿素生物合成之间的内在联系提供了优良的遗传材料。本研究鉴定了1份白叶白穗突变体wlwp7(white leaf and white panicle 7),分析了wlwp7的形态、生理和遗传特点。结果表明:wlwp7对低温敏感,当环境温度为20 ℃时苗期叶片白化,但温度升高至30 ℃后叶色正常;大田环境下wlwp7抽穗后颖壳白化,叶绿素含量降低至野生型的40.73%;除结实率较野生型T98B下降6.28%外,其他产量性状不受影响;遗传分析发现,wlwp7与T98B的正反杂交F2群体中都未出现白叶绿穗和绿叶白穗重组单株,经卡方检测白叶白穗突变单株与绿叶绿穗野生型单株的理论分离比符合1∶3,表明白叶白穗性状受同一隐性核基因控制;利用BSA策略进一步将wlwp7定位在第3染色体上一个280 kb的区域内,该区域未有已报道的白叶白穗基因。本研究发现了wlwp7同时控制叶部和穗部叶绿素合成,精细定位结果为最终克隆wlwp7奠定了基础。  相似文献   

16.
 采用硝酸盐利用缺陷突变体(Nitrate non utilizing mutants, nit)为遗传标记研究了稻瘟病菌对异稻瘟净的抗药性在无性重组过程中的遗传学。在DY2 3(nit1 LR)×A7 3(nitM S)、A7 3(nitM S)×F4 2(nit1 MR)和F4 2(nit1 MR)×DY2 4(nitA LR)3个配对组合中都检测到了无性重组体,重组频率分别为7.31%、14.00%和8.63%。大多数无性重组体都有较好的生长、产分生孢子能力和致病力,表明无性重组体有较高的适合度。这些结果说明由菌丝融合导致的无性重组在稻瘟病菌对异稻瘟净的抗药性群体发展中可能起着重要的作用。  相似文献   

17.
旱稻品种IRAT109辐照诱变突变体的筛选和鉴定   总被引:1,自引:0,他引:1  
利用γ射线辐照处理旱稻品种IRAT109的干种子样品,加代至M2后混收种子,分批在水田和干旱胁迫条件下种植M3群体,通过苗期、分蘖期和抽穗期的观察获得突变单株,加代繁育至M5后考查可稳定遗传的突变性状,共获得260份不同性状的突变体。介绍了其中部分突变体在叶片、茎秆、穗部、籽粒形态和抗旱性等方面表现,配制个别突变体与野生型的F2群体并初步观察分离比例。讨论了筛选抗旱性相关突变体的技术困难和该套突变体群体的应用价值。  相似文献   

18.
Water is becoming more and more limiting factor of sugar beet production and the productivity of the crop can be significantly improved by increased drought tolerance. It is therefore a great challenge to assess the degree of variability of anatomical and morphological traits of breeding material with respect to water use efficiency and drought, that can be used as potential markers for selection of sugar beet genotypes with better tolerance to water shortage. To achieve this, the first step is to assess the degree of genetic variability with respect to anatomical and histological features linked to water management in plants, under optimal water supply. Comparative histiological analysis of lamina and petiole was done on 12 sugar beet genotypes which previously showed divergent responses to lack of water in the field. The plants were grown in semi-controlled conditions of a glasshouse, and watered daily. Mircromorphological analyses were done to assess leaf epidermal characteristics, by both light and SEM, and lamina and petiole histological features. The measurements were used to calculate the percentage of individual tissues in relation to the thickness of the lamina, main vein area and petiole area. The general structure of sample variability was established by principal component analysis (PCA), based on correlation matrix. In majority of genotypes the ratio of the size of cells of spongy parenchyma and palisade cells in average was 80%. Low genotypic variability of the studied histological parameters of the lamina and petiole may reflect the narrow genetic base of tested breeding material. The most significant genotypic difference, considering leaf epidermal tissue, was in % of adaxial and abaxial epidermis. The highest found number of stomata per mm2 on both adaxial and abaxial epidermis was 40% higher than the lowest. During water stress, when stomata are closed, plant survival depends on the amount of water lost through the cuticle. SEM analysis of adaxial epidermis of the lamina show that cuticle varies in texture. Considering the observed genotypic variability in cuticle ornamentation and the fact that plants develop various strategies of adaptation to drought, finding genotypes with increased drought tolerance could be based on the characteristics of the cuticle and epidermis.  相似文献   

19.
以粳稻品种农大3号为材料,利用盆栽的方式人工控制土壤水分(水势),研究了不同生育时期干旱胁迫对水稻产量及碾米品质的影响。各时期干旱均导致产量下降,其敏感程度依次为:孕穗中期(抽穗前11~20 d)>孕穗后期(抽穗前1~10 d)>分蘖中期(移栽后11~20 d)>孕穗前期(抽穗前21~30 d)>分蘖初期(移栽后1~10 d)>分蘖后期(移栽后21~30 d)>乳熟期(抽穗后31~40 d)>抽穗开花期(抽穗后1~10 d)>灌浆期(抽穗后21~30 d)>蜡熟期(抽穗后41~50 d)。抽穗前干旱胁迫的敏感时期主要是孕穗中期、孕穗后期和分蘖中期。抽穗后,抽穗到乳熟期均较蜡熟期对干旱敏感,但对土壤水分变化较抽穗前迟钝。抽穗前干旱胁迫对糙米率和精米率影响最大的时期为孕穗中期,其次为孕穗后期。灌浆期到蜡熟期干旱胁迫,糙米率和精米率明显下降,抽穗后11~40 d干旱胁迫对整精米率的影响最大,其次为抽穗前1~20 d,其他时期干旱虽对整精米率有一定影响,但影响较小。  相似文献   

20.
大豆抗感SCN基因的一个RAPD标记   总被引:8,自引:1,他引:7  
对组合RNg(抗)× 7705(感)的P1、P2、F1、F2、BC1F1和BC1F2分离群体进行抗病性鉴定,遗传分析的结果表明,大豆对SCN1号小种的抗性由4对相互独立的主基因、包括一对显性基因和三对重叠的隐性基因决定。用 BSA法筛选在五个 BC1F2分离家系内具有多态性的 RAPD标记,发现 RAPD标记 OPA0191200在亲本间及 BC1F2分离群体内具有多态性,只能在感亲、 BC1F2家系 11和 43的感病单株中扩增出来,表明和这两个家系独有的感病基因有关。  相似文献   

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