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121.
高产优质藕莲新品种选育研究   总被引:1,自引:0,他引:1  
本文对我国现有野生和栽培藕莲品种进行了广泛的实地调查、引种栽培及生物学特性的详细观察,分析了我国当前藕莲生产中存在着的一些问题,如品种品质差,产量低,病虫害严重等。1979—1989年作者进行了藕莲的无性系优良单株的选育研究,从85个号中逐级选择,通过单株培育,小区试验,大田示范试验,现已选育出一个平均亩产2410.3kg,最高单产3000kg的‘武植二号’新品种;其成分为淀粉工3.5%,全糖4.09%,还原糖1.03%,分别高于对照的10.3%,3.7%和0.95%。水份为76.27%,粗纤维为2.63%,分别比对照低81.56%,4.26%;维生素E是对照的6倍。在连续10年的栽培中,未发生一期病害;证明‘武植二号’是一个适合于江汉平原湖区推广种植的优良藕莲新品种。  相似文献   
122.
莲藕组织总RNA的快速提取方法   总被引:12,自引:1,他引:12  
莲藕组织富含多糖、脂质、酚类等物质,用一般的方法较难提取高质量的RNA。在改进前人方法的基础上,建立了一种高效、简单的CTAB-LiCl提取法,能快速提取高质量的莲藕组织总RNA,并且产率高、完整性好、纯度高,能进一步满足RT-PCR等分子生物学实验的需要。此外,该方法也适用于其它富含多糖、脂质、酚类等物质的植物组织总RNA的提取。  相似文献   
123.
为了探索同时测定荷叶茶及饮片中6种黄酮类成分(芦丁、金丝桃苷、紫云英苷、槲皮素、山奈素和异鼠李素)含量的方法,本研究以8种不同的荷叶样本为材料,采用高效液相色谱分析法对6种黄酮类成分进行了同时测定。样品经过前处理,以0.5%甲酸-水(A)和0.1%甲酸-乙腈(B)作为流动相进行梯度洗脱,流速为1mL/min,柱温为25℃,进样量为20μL,经Agilent TC-C18(2)(150mm×4.6mm,5μm)色谱柱分离,于360nm波长处检测,结果显示,芦丁、金丝桃苷、紫云英苷、槲皮素、山奈酚、异鼠李素6种黄酮类成分分别在1.6~160、1.8~180、2.16~216、1.4~140、2.12~212、1.6~160μg/mL浓度范围内有良好的线性关系(R20.9992),其检测稳定性、重复性、日内精密度、日间精密度以及加样回收率的RSD均小于2%。进一步用该方法对不同来源的8个荷叶样本进行检测,结果显示荷叶样本中6种黄酮类成分含量以槲皮素最高,并且以样本G荷叶茶(购自G公司,批号为130802)的槲皮素含量最高。本研究建立的同时测定6种荷叶黄酮类成分含量的方法快速、准确,可为荷叶有效成分的检测和质量控制提供技术支撑。  相似文献   
124.
125.
High levels of naturally occurring selenium (Se) are often found in conjunction with different forms of salinity in central California. Plants considered for use in phytoremediation of high Se levels must therefore be salt tolerant. Selenium accumulation was evaluated for the following species under increasing salt (NaCl and CaCl) conditions:Brassica napus L. (canola),Hibiscus cannibinus L. (kenaf),Festuca arundinacea L. (tall fescue), andLotus tenuis L. (birdsfoot trefoil). The experimental design was a complete randomized block with four salt treatments of <1, 5, 10, and 20 dS m-1, four plant species, three blocks, and six replicates per treatment. Ninety days after growing in the respective salt treated soil with a Se concentration of 2 mg Se kg-1 soil, added as Na2SeO4, all plant species were completely harvested. Among the species tested, shoot and root dry matter yield of kenaf was most significantly (p<0.001) affected by the highest salt treatment and tall fescue and canola were the least affected species. Generally there was a decrease in tissue accumulation of Se with increasing salt levels, except that low levels of salinity stimulated Se accumulation in canola. Canola leaf and root tissue accumulated the highest concentrations of Se (315 and 80 mg Se kg-1 DM) and tall fescue the least (35 and 7 mg Se kg-1 DM). Total soil Se concentrations all harvest were significantly (p<0.05) lower for all species at all salt treatments. Removal of Se from soil was greatest by canola followed by birdsfoot trefoil, kenaf and tall fescue. Among the four species, canola was the best candidate for removing Se under the tested salinity conditions. Kenaf may be effective because of its large biomass production, while tall fescue and birdsfoot trefoil may be effective because they can be repeatedly clipped as perennial crops.  相似文献   
126.
在正常栽培条件下,钵或缸栽荷花的花期是从6月中旬到8月。但用分蔤栽培繁殖技术,可使花期延长到10月上旬。这是延长花期的一种栽培繁殖方法。本文介绍了这一技术的要点和试验结果。  相似文献   
127.
1985年7月3日至8月15日,在美国加利福尼亚州Modesto市太平洋企业公司莲园播种168组莲花种子约1000粒,保存568株苗,有35个组合的56株苗当年开了花,其中部分植株从播种到开花只需30至35天。绝大多数的植株在霜冻期来临之前都能自然结束其年生长期,但有一部分则不能。后者继续旺盛生长,直到霜期到来时叶片被冻死。这些现象表明,莲花的不同遗传类型之间,存在着对日照和温度的不同反应。  相似文献   
128.
Summary Crosses between male sterile L. corniculatus (2n=4x=24) and L. tenuis (2n=2x=12) plants were performed in order to verify the presence of 2n gametes in L. tenuis. All but one of the plants from these crosses had 2n=4x=24 and the L. corniculatus phenotype; this plant had 2n=2x=12 and the L. tenuis phenotype. The plants also showed good quantity of pollen at tripping, good pollen fertility and good percentage of seed setting in the backcross to L. corniculatus. On the whole, both cytological and morphological observations, showing that all but one of the plants from L. corniculatus x L. tenuis were normal tetraploids, suggest the existence of diploandrous gametes in L. tenuis. On the other hand, haploid parthenogenesis probably gave origin to the dihaploid plant 2n=2x=12.  相似文献   
129.
Summary An achlorophyllus isoline originated spontaneously from a green callus line derived from a genotype ofLotus corniculatus L. cv. Leo. This isoline is characterized by significantly faster callus growth than the green line and by differentiating significantly fewer plants per gram of callus when subcultured on a shoot differentiating medium. The isoline does, however, develop loci of meristematic cells when transferred from a medium containing 2,4-D to one containing benzyl adenine. After this transfer, plastids, mitochondria, dictyosomes, and endoplasmic reticulum appear to be more prevalent in many cells. Nuclei and nucleoli become more prominent in these cells. Ingrowths, lined with plasmalemma, develop along the outer tangential cell wall of many cells in contact with the culture medium and along various walls of cells found in the interior of the callus. These cells have characteristics of transfer cells. A few cells at the periphery of meristematic groups of cells elaborate lamellar structures similar to suberin lamellae in their cell walls.  相似文献   
130.
We determined the nucleotide sequences of 64 TAC (transformation-competent artificial chromosome) clones selected from genomic libraries of Lotus japonicus accession Miyakojima MG-20 based on the sequence information of expressed sequence tags (ESTs), cDNAs, genes and DNA markers from L. japonicus and other legumes. The length of the DNA regions sequenced in this study was 6,370,255 bp, and the total length of the L. japonicus genome sequenced so far is 32,537,698 bp together with the nucleotide sequences of 256 TAC clones previously reported. Five hundred forty-eight potential protein-encoding genes with known or predicted functions, 127 gene segments and 224 pseudogenes were assigned to the newly sequenced regions by computer prediction and similarity searches against the sequences in protein and EST databases. Based on the nucleotide sequences of the clones, simple sequence repeat length polymorphism (SSLP) or derived cleaved amplified polymorphic sequence (dCAPS) markers were generated, and each clone was genetically localized onto the linkage map of two accessions of L. japonicus, MG-20 and Gifu B-129. The sequence data, gene information and mapping information are available through the World Wide Web at http://www.kazusa.or.jp/lotus/.  相似文献   
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