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本文通过对半夏属Pinellia 5个种10个群体的染色体计数和珠芽数量统计,首次报道了5个染色体数目,同时发现珠芽的发生与染色体基数及多倍化程度有关:x=13的类群无珠芽,而x=9的有珠芽;在有珠芽的半夏P.ternata(Thunb.)Breit.中,平均每叶珠芽数随倍性的提高而增大。半夏是一个多倍体复合种,起源于无珠芽、染色体基数为x=7~9的二倍体祖先,可能是在该属的早期进化中由鹞落坪半夏P.yaoluopingensis X.H.Guo et X.L.Liu的x=13经非整倍性跌落而成,在发生上比鹞落坪半夏进化。 相似文献
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用块茎根尖、试管苗根尖及组培苗移栽后未膨大的匍匐茎尖为材料鉴定马铃薯的倍性,利用匍匐茎尖作为材料,用饱和的对二氯溶液处理12~24h后,用改良的卡洛氏固定液同定8~12h,用1M的HCl解离5~15min,进行染色15~20min,效果很好,说明在不易取材或材料稀少的情况下,用匍匐茎尖制片是一个鉴定马铃薯染色倍性的经济有效方法. 相似文献
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目的:分析秋水仙素诱导细叶百合多倍体的效果,总结诱导经验和方法:取细叶百合种,分别采用0.05%、0.10%、0.20%秋水仙碱溶液浸泡处理24h、48h、72h,诱导变异,接种栽培;取30变异株植株与正常的植株进行对比,测量形态学特征、染色体鉴定。结果:0.10%处理48h的变异率最高,达到30%;多倍体出现率为16.67%(5/30)。结论:秋水仙素可诱导细叶百合变异为多倍体。 相似文献
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再生混凝土抗渗性试验研究 总被引:1,自引:0,他引:1
文章在分析再生混凝土产生渗透原因的基础上,指出用相对渗透系数评价再生混凝土要比抗渗标号更加合理,并给出了相对渗透系数的测定方法,并在大量试验的基础上对影响再生混凝土的因素进行了详细分析,得出了各因素对再生混凝土抗渗性的影响规律。 相似文献
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要搞好翻译,必须处理好语言中所包含的文化因素.人类文化的共性决定了其可译性,但各民族文化之间存在的更多的是其特殊性,这就使得其可译性产生了限度.我们可用不同的翻译方法来解决不可译性问题.然而在文学翻译中,文化信息的流失是不可避免的,译者应当高度重视文化差异,使这种流失降到最低限度. 相似文献
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小儿脑性瘫痪早期诊断避免误诊的临床分析 总被引:2,自引:0,他引:2
目的研究小儿脑性瘫痪早期诊断避免误诊的方法。方法将2002年~2003年收治脑瘫患儿121例进行病因,临床分类,误诊率,误诊时间进行分析。结果121例脑瘫患儿入院前早期误诊85例,误诊率为70%,80%有病因,常见窒息,早产,高胆红素血症等,误诊疾病有佝偻病68例,癫痫9例,智力低下5例,染色体及遗传代谢病3例,误诊时间多为6个月以内。结论小儿脑性瘫痪早期诊断避免误诊应当注意病因(围产期高危因素),早期表现,异常姿势,反射异常,肌张力异常,结合CT等辅助检查就可明确诊断避免误诊。 相似文献
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BackgroundWheat is one of the most important crops cultivated all over the world. New high-yielding cultivars that are more resistant to fungal diseases have been permanently developed. The present study aimed at the possibility of accelerating the process of breeding new cultivars, resistant to eyespot, by using doubled haploids (DH) system supported by marker-assisted selection.ResultsTwo highly resistant breeding lines (KBP 0916 and KBH 4942/05) carrying Pch1 gene were crossed with the elite wheat genotypes. Hybrid plants of early generations were analyzed using endopeptidase EpD1 and two SSR markers linked to the Pch1 locus. Selected homozygous and heterozygous genotypes for the Pch1-linked EpD1b allele were used to produce haploid plants. Molecular analyses were performed on haploids to identify plants possessing Pch1 gene. Chromosome doubling was performed only on haploid plants with Pch1 gene. Finally, 65 DH lines carrying eyespot resistance gene Pch1 and 30 lines without this gene were chosen for the eyespot resistance phenotyping in a field experiment.ConclusionsResults of the experiment confirmed higher resistance to eyespot of the genotypes with Pch1 in comparison to those without this gene. This indicates the efficiency of selection at the haploid level.How to cite: Wiśniewska H, Majka M, Kwiatek M, et al. Production of wheat doubled haploids resistant to eyespot supported by marker-assisted selection. Electron J Biotechnol 2019;37. https://doi.org/10.1016/j.ejbt.2018.10.003 相似文献
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刺五加的有性生殖与营养繁殖 总被引:4,自引:0,他引:4
刺五加 Eleutherococcus senticosus (Rupr.et Maxim.)Maxim,既可进行有性繁殖,又可进行营养繁殖。本文报道其三类花丝长度不同的植株每个花序的花朵数量、座果率、饱满种子率及根茎形态和形态发生的某些特点。通过人工受精,检测了其繁育系统。结果表明:长花丝植株不座果,短花丝植株座果,但不同年份、不同生境中座果率不同,中花丝植株也座果但饱满种子率教低。在正常年份,短花丝植株的座果率接近40%,并且林缘的座果率稍高于皆伐迹地和次生林下的。考虑到中花丝植株在所研究地区居群数很少,我们认为绝大多数刺五加种子是异花传粉的产物,其有性生殖与营养繁殖相配合,在无人为破坏的前提下,该物种不应该濒危。 相似文献
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《Electronic Journal of Biotechnology》2014,17(1):6-13
BackgroundThe quality of wheat grain depends on several characteristics, among which the composition of high molecular weight glutenin subunits, encoded by Glu-1 loci, are the most important. Application of biotechnological tools to accelerate the attainment of homozygous lines may influence the proportion of segregated genotypes. The objective was to determine, whether the selection pressure generated by the methods based on in vitro cultures, may cause a loss of genotypes with desirable Glu-1 alleles.ResultsHomozygous lines were derived from six winter wheat crosses by pollination with maize (DH-MP), anther culture (DH-AC) and single seed descent (SSD) technique. Androgenetically-derived plants that originated from the same callus were examined before chromosome doubling using allele-specific and microsatellite markers. It was found that segregation distortion in SSD and DH-MP populations occurred only in one case, whereas in anther-derived lines they were observed in five out of six analyzed combinations.ConclusionsSegregation distortion in DH-AC populations was caused by the development of more than one plant of the same genotype from one callus. This distortion was minimized if only one plant per callus was included in the population. Selection of haploid wheat plants before chromosome doubling based on allele-specific markers allows us to choose genotypes that possess desirable Glu-1 alleles and to reduce the number of plants in the next steps of DH production. The SSD technique appeared to be the most advantageous in terms of Mendelian segregation, thus the occurrence of residual heterozygosity can be minimized by continuous selfing beyond the F6 generation. 相似文献
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研究了15、25和35℃三种温度下四棱豆的发芽特性以及三播期下的生育特性.结果表明,随着温度的升高,正常发芽率提高,非正常发芽率和霉烂率下降,且以浸种为优.不管早播还是迟播,初花期均在9月初;花荚脱落的高峰期在开花后的2~5天,总脱落率为70%以上. 相似文献
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比较了反射仪—K+试纸法(K+ts-fl)、原子吸收光谱法、ICP–aeS法测定烟株叶脉汁液中的K+含量的三种方法,确定反射仪—K+试纸法测定烟株钾含量的可行性及其最佳测定范围;在烤烟不同生育期,应用反射仪—K+试纸法对烟株叶片不同部位含K+水平的测定,确定其最佳测定时期及部位。研究结果表明,反射仪—K+试纸法与原子吸收光谱法、ICP–aeS法测定结果差异不显著,应用反射仪—K+试纸法进行烟株钾素快速诊断可行,且具有时间短,简单快速,易操作等优点。反射仪测定K+的稳定线性范围是0.30g/L~0.9g/L;在不同时期对烟株不同部位测定研究表明,最佳诊断部位为烟株第二平展叶叶脉基部2cm段。 相似文献
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短柄五加Eleutherococcus brachypus Harms种子为扁肾形,种皮由一层细胞构成。种子脱落时,胚
为心形胚期,胚周围的胚乳细胞解体形成液样囊腔,并包裹胚,胚细胞中存在较多蛋白质,胚乳细胞贮
存大量蛋白质颗粒和脂类,但两者均未见多糖颗粒。有萌发潜能的种子只占全部种子的9.27%。在试
验地种植条件下饱满种子经18~19个月后萌发,出苗率为1.67%,该过程细胞化学特点是胚细胞中蛋
白质含量逐渐减少,并逐渐积累少量多糖颗粒。种子经变温层积处理6个月即可完成后熟过程,其细胞
化学特点是胚细胞中蛋白质含量逐渐减少,但在心形胚后期即已积累大量多糖颗粒,并一直保持至胚
完全发育成熟。经比较短柄五加与刺五加的种子结构、后熟作用及其细胞化学特点,认为短柄五加种子质量差、自然状态下后熟时间长和出苗率低是短柄五加致濒的重要生殖因素,并提出了相应保护方法。 相似文献
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运用三元能量处理5个油菜品种,同时设对照,进行试验,产量统计结果是,处理的对照相比人武部增产,增幅为3.01%-13.18%,平均为8.48%,t-检验表明增产显著。经济性状调查结果是,三元能量处理与对照相比,平均株高增加3.46cm,平均有效分数增加0.38个,平均有较分枝部位降低2.69cm,平均单株角果数增加2.92个,平均角果粒数增加0.24粒,千粒重增加0.15g。 相似文献