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51.
六种唇形科种子营养成分比较分析 总被引:3,自引:0,他引:3
对六种唇形科植物种子营养成分研究的结果表明:种子含有丰富的脂肪油,其不饱和脂肪酸总量均在90%以上。种子油的主要成分为:α-亚麻酸、亚油酸、油酸、花生烯酸、棕榈酸和硬脂酸等成分。并从种子中测定了18种氨基酸和多种矿质元素的含量。这六种种子和种子油具有较高的营养价值和潜在药用保健功效。 相似文献
52.
Flow cytometric analysis with 4,6-diamidino-2-phenylindole (DAPI) staining was used to screen for chromosomal changes in Quercus robur during in vitro culture. The initiated cell lines (1992 until 1999) were maintained via secondary embryogenesis on P24 medium with 0.9 M 6-benzylaminopurine (BAP) in regular subculture intervals of 6 weeks. Regenerated plants established in the greenhouse and in vitro plantlets derived from encapsulated somatic embryos were screened. The embryogenic cell lines were characterized as individual clones by isoenzyme analysis. Flow cytometric relative DNA content analysis of the first screening period revealed that somaclonal variation in form of tetraploidy occurred in two out of 26 tested somatic embryo clones (Alt and Jung). These two clones lost their ability to convert into plantlets. Intraspecific relative DNA content variation including technical variation was below 3 %. In the second screening period, however, 3 out of 37 clones (Alt, E4.31H9 and P3.27H) contained tetraploid cells leading to the assumption that the frequency of tetraploidy seems to be correlated with the duration of in vitro culture. No chromosomal differences were detected in regenerated plants. However, tetraploidy occurred in 8 % of the tested clones over a culture period of 7 years. 相似文献
53.
Protein-L-isoaspartate (D-aspartate) O-methyltransferases (EC 2.1.1.77) that catalyze the transfer of methyl groups from S-adenosylmethionine to abnormal L-isoaspartyl and D-aspartyl residues in a variety of peptides and proteins are widely distributed in procaryotes and eucaryotes. These enzymes participate in the repair of spontaneous protein damage by facilitating the conversion of L-isoaspartyl and D-aspartyl residues to normal L-aspartyl residues. In this work, we have identified an L-isoaspartyl methyltransferase activity in Arabidopsis thaliana, a dicotyledonous plant of the mustard family. The highest levels of activity were detected in seeds. Using degenerate oligonucleotides corresponding to two highly conserved amino acid regions shared among the Escherichia coli, wheat, and human enzymes, we isolated and sequenced a full-length genomic clone encoding the A. thaliana methyltransferase. Several methyltransferase cDNAs were also characterized, including ones that would encode full-length polypeptides of 230 amino acid residues. Messenger RNAs for the A. thaliana enzyme were found in a variety of tissues that did not contain significant amounts of active enzyme suggesting the possibility of translational or posttranslational controls on methyltransferase levels. We have identified a putative abscisic acid-response element (ABRE) in the 5-untranslated region of the A. thaliana L-isoaspartyl methyltransferase gene and have shown that the expression of the mRNA is responsive to exogenous abscisic acid (ABA), but not to the environmental stresses of salt or drought. The expression of the A. thaliana enzyme appears to be regulated in a distinct fashion from that seen in wheat or in animal tissues. 相似文献
54.
酿酒葡萄品质评价及其对气象条件的响应 总被引:26,自引:0,他引:26
根据2004~2005年我国北方6省酿酒葡萄主要产区葡萄取样和宁夏芦花台园艺场田间试验葡萄化验结果,运用层次分析方法(AHP)对酿酒葡萄主要品质因子总糖、糖酸比pH、单宁进行综合评价,运用主成分分析方法和因子分析法研究影响每个地区酿酒葡萄综合品质的主要气象因子和影响时段。结果表明:2004~2005年贺兰山东麓的御马、玉泉营、广夏三基地、贺东在庄园;河西走廊的高台、武威;新疆石河子酿酒葡萄品质优良,渤海湾的烟台、蓬莱、昌藜等地酿酒葡萄品质表现一般。酿酒葡萄综合品质主要受果实着色期、全生育期和7~8月的降水量和水热系数的影响,其中降水量起主导作用。果实着色期气温日较差和全生育期平均相对湿度对酿酒葡萄综合品质的形成也有重要影响,影响相对较小的是果实着色期的最低气温。采样地区的光照、温度等气象条件基本适宜酿酒葡萄品质形成,对优质酿酒葡萄形成没有大的限制作用。 相似文献
55.
控制大豆白花亲本籽粒脐色的基因有带R与r之分,带R基因的白花产本与紫花亲本杂交,F1代籽料出现蓝脐性状,其基因型为I-R-W1-tt。当控制脐色的基因有两对相差时(R、r;W1、w1)F2代籽粒脐色分离蓝脐与无色脐之比为9∶7。 相似文献
56.
57.
We compared various aspects of the seed biology of eight non-pioneer tree species from a tropical seasonal rain forest in
Xishuangbanna, SW China, that differ in time of dispersal, size and fresh seed moisture content (MC). Seeds were tested for
germination under laboratory conditions after dehydration to different moisture levels and under 3.5, 10 and 30% solar irradiances
in neutral-shade houses. For six species, germination was also compared in forest understory (3.5% light) and center of a
forest gap (32.5% light). Under continuous dehydration over activated silica gel, 100% of seeds of four species had lost the
ability to germinate after 48 h, and those of all species except Castanopsis hystrix (decreased from >90 to 30% germination) had lost the ability to germinate after 120 h. Four species did not differ in final
germination percentages at the three irradiances (i.e. uniform germination). However, final germination percentages of Horsfieldia pandurifolia and Litsea pierrei var. szemaois were significantly lower in 30% than in 10 or 3.5% light, and seeds of Antiaris toxicaria and C. hystrix germinated to higher percentages in 30 and 10% than in 3.5% light. Mean time to germination (MTG) of the eight species (forest
and shade house data combined) ranged from 5–5 days for Pometia
tomentosa to 72–207days for L. pierrei; MTG for four species was ≤21 days. There was no obvious relationship between relative desiccation resistance and either
time of dispersal, MTG or uniformity of germination at the three light levels, or between seed size and MC or MTG. However,
the relationship between seed MC at maturity (25–60% fresh mass basis) and MC at 50% loss of seed viability (12.4–42.5%) was
significant. Seven of the species fit Garwood’s (Ecol Monogr 53:159–181, 1983) rapid-rainy germination syndrome and one, L. pierrei, either her delayed-rainy or intermediate-dry germination syndrome. However, fresh, non-dehydrated seeds of all eight species
germinated in ≤30 days at constant 30°C in light. 相似文献
58.
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60.
Wiktoria Ratajczak Sławomir Borek Arkadiusz Podgórski Lech Ratajczak 《Acta Physiologiae Plantarum》1999,21(4):413-417
A study on globulins, major storage proteins in yellow lupin seeds, called conglutins, was conducted using SDS polyacrylamide
gel electrophoresis. In this paper, an extensive and not yet published list of yellow lupin conglutins is presented. The patterns
of subunits of major conglutins in seeds of three yellow lupin cultivars were similar to each other, varying only in the level
of some polypeptides. Investigations of seeds of cultivar Parys showed considerable quantitative differences in major subunits.
Some minor subunits occurred only in some seeds and were absent in the others. Great differences were shown between single
individuals in the amount of subunits of conglutin which is of the most nutritional value due to high content of methionine. 相似文献