首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Summary Siblings of Abutilon theophrasti, were grown on a nutrient gradient. The plants grown at higher nutrient levels were larger and produced larger and more seeds than plants grown at lower soil nutrient concentrations. There were no differences in germinability of seeds, but the competitive abilities of resulting plants were markedly different.In two different competition experiments designed to eliminate the effects of genotype, seed size, and germination time, by using synchronously germinated seedlings derived from similar size seed from plants grown at different nutrient levels, we found that plants from seeds produced at higher nutrient levels consistently, outperformed plants from seeds produced at the lower nutrient levels. The dominance of seeds produced at higher nutrient levels may be explained by the fact that they had markedly higher concentrations of nitrogen than did seeds produced at lower soil nutrient levels. The additional advantage of increased seed quality to plants controlling more of the nutrient resource than their neighbors would be expected to accelerate their contributions to the gene pool of the population.  相似文献   

2.
3.
The use of transgenic plants in the production of recombinant proteins for human therapy, including subunit vaccines, is being investigated to evaluate the efficacy and safety of these emerging biopharmaceutical products. We have previously shown that synthesis of recombinant glycoprotein B (gB) of human cytomegalovirus can be targeted to seeds of transgenic tobacco when directed by the rice glutelin 3 promoter, with gB retaining critical features of immunological reactivity (E.S. Tackaberry et al. 1999. Vaccine, 17: 3020-3029). Here, we report development of second generation transgenic plant lines (T1) homozygous for the transgene. Twenty progeny plants from two lines (A23T(1)-2 and A24T(1)-3) were grown underground in an environmentally contained mine shaft. Based on yields of gB in their seeds, the A23T(1)-2 line was then selected for scale-up in the same facility. Analyses of mature seeds by ELISA showedthat gB specific activity in A23T(1)-2 seeds was over 30-fold greater than the best T0 plants from the same transformation series, representing 1.07% total seed protein. These data demonstrate stable inheritance, an absence of transgene inactivation, and enhanced levels of gB expression in a homozygous second generation plant line. They also provide evidence for the suitability of using this environmentally secure facility to grow transgenic plants producing therapeutic biopharmaceuticals.  相似文献   

4.
5.
The furanocoumarin content of ripe seeds of seven cultivars of Pastinaca sativa was compared to that of ripe seeds from a naturalized population in central Illinois. Five furanocoumarins were identified and quantified in the intact seeds. While seeds of wild and cultivated plants contain furanocoumarin components in identical proportions, seeds from wild plants contain almost three times the quantity of furanocoumarins on a dry weight basis as do seeds of cultivars.  相似文献   

6.
The amount and composition of the essential oil from leaves of Hypericum androsaemum L. cultivated in Arouca (Portugal) were determined in six samples harvested during 1 year at intervals of 2 months. The seasonally dependent essential oil content ranged from 0.7 mg/g biomass dry weight in September to 3.4 mg/g in February. The oil contained more than 80 compounds, 70 of which (constituting 88-93% of the total oil) were identified by GC and GC-MS. An approximation of the absolute quantification of each compound and compound class was performed using a GC method with an internal standard. The relative and the absolute content of each compound and compound class changed during the year. At the end of the winter and in the spring, the essential oil was dominated by sesquiterpene hydrocarbons and accumulated a high number of intermediate to long chain n-alkanes and 1-alkenes. In September, the essential oil contained the lowest levels of sesquiterpene hydrocarbons (43%) and the highest levels of 1-octene and 2-hexenal (38%). In February, the essential oil had the highest level of sesquiterpene hydrocarbons (73%) and the highest diversity of intermediate to long chain n-alkanes and 1-alkenes.  相似文献   

7.
8.
The contents of the heterogenous group of polyisoprenoids was found about two orders of magnitude lower in seeds than the amount of polyprenols and/or their carboxylic esters accumulated during vegetation season in leaves. In contrast to leaves, no seeds were found containing more than 0.5 mg of these lipids per gram of dry tissue. Almost 50% had less than 0.01 mg/g - the amount which is the limit of detection by the procedure used in this work. In gymnosperms (10 representatives of Cupressaceae, Pinaceae and Taxaceae) the polyprenol spectra in seeds and in needles were similar. In angiosperms (25 representatives of 13 botanical families) the polyisoprenoid mixture in seeds resembled the minor, additional subfamily found in leaves.  相似文献   

9.
The ethnobotany of cultivated plants of the Maohi of the society islands   总被引:1,自引:0,他引:1  
Biases in the ethnohistoric literature of the Maohi have resulted in a misconception that cultivation practices were not well developed in the Society Islands. Though observations of cultivation practices are indeed few and far between in these sources, taken together they clearly indicate the importance of cultivated plants to many aspects of Maohi life. This paper documents 47 taxa, and many more varieties, that the Maohi relied on for food and technology. Cultivation techniques ranged from minimum tillage, to major modifications of the landscape. Few of these crops, and their associated cropping techniques, are used by the Maohi today.  相似文献   

10.
Summary Oats, vetch, and rye were grown as successive crops in pots of a manganese-deficient soil to which -MnO2 had been added in increasing amounts. Manganese deficiency of oats was overcome with 32 ppm of added manganese. Additions of 10, 18 and 32 ppm caused a decrease in concentration of maganese in the plants. Vetch and rye were unaffected by manganese deficiency and kept on accumulating manganese with increasing additions to the soil. Of the three plants vetch showed the greatest uptake of manganese, both with and without added manganese.  相似文献   

11.
12.
The content and composition of lipids were studied in the seeds of radish plants (Raphanus sativus L. var. radicula D.C., cv. Rosovo-krashyi s belym konchikom) grown from “seed to seed” in 2008 and 2009 in the greenhouse of the Institute of Plant Physiology in a permanent horizontal magnetic field (PMF) of Helmholz coils with the strength of ~400 A/m, in soil culture, at natural day length, and a temperature changing during the day. PMF suppressed all stages of radish plant development, from the appearance of alternative leaves to the formation of pods and mature seeds. In plants of the North-South magnetically oriented type (NS MOT), PMF reduced the number and weight of seeds; in the West-East magnetically oriented type (WEMOT), the number of seeds was reduced but their weights increased. In the seeds of the first generation of NS MOT, the total lipid content was higher than in the seeds of WE MOT. The amount of polar lipids in the seeds of NS MOT increased, whereas in the seeds of WE MOT it decreased or remained unchanged as compared with control. The content of neutral lipids reduced in both plant types. The strongest changes in the fatty acid composition of lipids with the highest content of unsaturated fatty acids were observed in the seeds of WE MOT in 2008. The weak PMF-induced differences in the changes of lipid composition and content in the seeds of different MOTs were evidently determined by seed sensitivity to the direction of field action. It is suggested that the occurrence of different MOTs increases the tolerance of plant population to unfavorable environmental factors, thus affecting its survival.  相似文献   

13.
14.
15.
Treatment of different plant materials, seeds of Phaseolus vulgaris, Zea mays and Pinus silvestris and young plants of Phaseolus, with kinetin increased the level of extractable IAA. For seeds this increase was most pronounced in bean seeds, which contained the lowest amount of endogenous IAA and cytokinins, and lower in maize seeds with high endogenous content of IAA and cytokinins. – For young bean plants the kinetin treatment significantly increased the extractable amounts of IAA from all parts of the plant, hypocotyls, cotyledons, epicotyls and primary leaves, when the cut plants were placed for 24 h in kinetin solution. For plants sprayed with kinetin solution only the primary leaves showed a significantly higher level of extractable IAA, which could be explained by the fact that the plants were growing very close together, so that the primary leaves received most of the kinetin during spraying.  相似文献   

16.
17.
18.
19.
20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号