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971.
Hempseed as a nutritional resource: An overview   总被引:7,自引:0,他引:7  
J. C. Callaway 《Euphytica》2004,140(1-2):65-72
Summary The seed of Cannabis sativa L. has been an important source of nutrition for thousands of years in Old World cultures. Non-drug varieties of Cannabis, commonly referred to as hemp, have not been studied extensively for their nutritional potential in recent years, nor has hempseed been utilized to any great extent by the industrial processes and food markets that have developed during the 20th century. Technically a nut, hempseed typically contains over 30% oil and about 25% protein, with considerable amounts of dietary fiber, vitamins and minerals. Hempseed oil is over 80% in polyunsaturated fatty acids (PUFAs), and is an exceptionally rich source of the two essential fatty acids (EFAs) linoleic acid (18:2 omega-6) and alpha-linolenic acid (18:3 omega-3). The omega-6 to omega-3 ratio (n6/n3) in hempseed oil is normally between 2:1 and 3:1, which is considered to be optimal for human health. In addition, the biological metabolites of the two EFAs, gamma-linolenic acid (18:3 omega-6; GLA) and stearidonic acid (18:4 omega-3; SDA), are also present in hempseed oil. The two main proteins in hempseed are edestin and albumin. Both of these high-quality storage proteins are easily digested and contain nutritionally significant amounts of all essential amino acids. In addition, hempseed has exceptionally high levels of the amino acid arginine. Hempseed has been used to treat various disorders for thousands of years in traditional oriental medicine. Recent clinical trials have identified hempseed oil as a functional food, and animal feeding studies demonstrate the long-standing utility of hempseed as an important food resource.  相似文献   
972.
镉处理对绿豆种子萌发及蛋白质含量的影响   总被引:1,自引:0,他引:1  
郑世英  王丽燕  商学芳 《种子》2007,26(1):28-30
采用室内试验方法,研究了不同浓度的Cd^2+溶液对绿豆种子萌发及蛋白质含量的影响。结果表明,当Cd^2+溶液浓度低于20mg/L时,种子的发芽率不受Cd^2+溶液浓度的影响;当Cd^2+溶液浓度低于10mg/L时,种子的发芽指数不受Cd^2+溶液浓度的影响;与对照相比。种子的活力指数与发芽势随着Cd^2+浓度的增加而下降。种子内的蛋白质含量随着Cd^2+溶液浓度的提高而升高,而蛋白酶活性和自由氨基酸的含量均下降。  相似文献   
973.
水合—脱水处理在烤烟种子活力中的作用   总被引:3,自引:0,他引:3  
白永富  王荔  王绍坤 《种子》2001,(2):22-23
对不同活力水平烤烟K326种子进行水合-脱水处理,并用生理及生化指标对不同处理进行测定与分析。结果表明,水合-脱水处理种子后,可提高中、低等活力水平种子的活力,而对高活力的种子的活力则有轻微的抑制作用,在水合-脱水处理中,以水分平衡-浸泡-干燥处理的效果最佳。这对提高中、低等活力水平种子的活力具有显著效果。  相似文献   
974.
分析了朱鹮自然保护区的自然环境、生产环境和社会人文环境,以及朱鹮自然保护区发展有机产品的可行性。进一步论述了朱鹮保护区有机产品产业环境的构成,在此基础上建立了朱鹮保护区有机产品产业环境的评价体系:目标层、项目层、评价因素层和指标层;政策体系:国家法律体系、政府行政体系、民俗民约体系;评价监控管理体系:国家法律、政府行政、经济活动方面和管理过程方面,并对这一评价体系的应用前景进行了展望。保护朱鹮自然保护区有机产品产业环境是一项长期艰巨的任务。建立朱鹮自然保护区有机产品产业环境评价体系具有广阔的应用前景,主要体现:能为有机产品产业提供有效的管理方法;可供政府管理、监控、指导产业发展,以及能为投资决策提供依据。  相似文献   
975.
Summary A landrace seed lot of runner bean (Phaseolus coccineus L.), obtained from the Budapest region, Hungary, was separated into five seed groups according to seed coat colour. 131 plants were grown randomly, and observed for 27 morphological and physiological characters. The collected data were analysed by ANOVA.Numerical taxonomy of the data employed Principal Components Analysis to generate scatter diagrams and Cluster Analysis to generate dendrograms, both before and after removing data on the four anthocyanin colour characters (seed coat, calyx, stem and flower colour) as these characters are probably controlled by a single major gene. The progenies from the five distinct parental seed groups showed much overlap in characteristics, indicating that they were not distinct lines but comprised a largely panmictic population.Some character associations were detected: plants from white seeds matured significantly later than those from black seeds, plants from white seeds with a few dark spots produced seeds significantly heavier than average, whereas those from white or black seeds produced significantly lighter seeds, although the average seed yield per plant did not differ significatly.  相似文献   
976.
Salinity is a major stress condition. Salicornia bigelovii is a valuable edible halophyte, considered to be a promising resource for cultivation in arid coastal zones. Its productivity depends on the supplementary provision of nitrogen, for which an option is chemical fertilization. Nevertheless, indiscriminate use of chemical fertilizers contributes to the problem of increased salinity. The inoculation of plant growth‐promoting bacteria (PGPB) represents an alternative. Seed ecotypes from four coastal areas [Santa Rosa Chica, Santa Rosa Grande, Santa Cruz and Cerro Prieto (CP), Sonora, México] were collected, in order to inoculate them with two species of PGPB (Azospirillum halopraeferens and Klebsiella pneumoniae). Two germination tests were carried out to study the effect of salinity, temperature regime (night/day) and inoculation with PGPB on germination (percentage and rate), plant height, root length and biomass produced (fresh and dry matter). In the first test, all four ecotypes were considered, whereas in the second test only the CP ecotype was involved because it was found to be the outstanding ecotype in the previous test. Results showed inhibition of germination when salinity was higher in all ecotypes except CP. The CP ecotype showed a decrease of seed germination with an increase in NaCl concentrations at all temperatures tested. However, when it was inoculated with both PGPB, the germination percentage was influenced.  相似文献   
977.
S. P. Singh    J. A. Gutierrez    C. A. Urrea    A. Molina  C. Cajiao 《Plant Breeding》1992,109(4):320-328
Two populations of common bean, Phaseolus vulgaris L., were used to make three independent location-specific selections at Palmira, Quilichao, and Popayán, Colombia. Also, three across-location selections were made by alternating generations between Palmira and Popayan, between Quilichao and Popayán, and among Palmira, Quilichao, and Popayán. The seven highest yielding lines selected from each environment and population along with 14 parents and two checks were evaluated for seed yield, seed weight, maturity, and reaction to an-thracnose, angular leaf spot, and common bacterial blight. Mean squares due to evaluation and selection environments, selected lines, and their interactions were significant for all traits. Mean yields of selected lines were higher than the mean of parents in both populations. Among location-specific selections, lines yielded higher at their respective selection site. Moreover, selections made at Popayán were higher yielding than those made at Quilichao or Palmira when tested across locations and years. Use of Popayán, a relatively wetter and cooler site, either alone or in combination with other locations resulted in higher yield, higher seed weight, and higher resistance to anthracnose. On the average, location-specific selections were lower yielding than the across-location selections. Among across-location selections, those selected between Palmira and Popayán were the highest yielding in both populations. Selections at Palmira and across all three locations resulted in greater stability.  相似文献   
978.
A. R. McElroy 《Euphytica》1991,57(2):117-123
Summary A breeding program aimed at improving the seed yield in bean for processing was started. Six parents divergent in a range of agronomical characters were crossed according to diallel mating design. Cluster analysis performed on the composite cross population evidenced divergence between F1 hybrids and to maximize genetic recombination, the most different F1 hybrids were intercrossed. A Factor analysis was performed on 7 morphological and yield-determining traits of 15 hybrids F1 and parents. Three Factors, representing patterns of variables interpreted as productivity per plant, growth factor, and branching-productivity, were extracted. These results evidenced the inverse relationship between seed yield components (seeds/pod, pods/plant, and hundred seed weight): i.e. the selection for either variable is detrimental to the other. It may be possible to break this association if the plant construct assures high sink to satisfy all plant requirements: tall and large plants bearing numerous nodes, leaves and reproductive structures. Moreover, the selection practiced simultaneously on the yield components positively affected the seed yield trait. An index of selection and response to selection were estimated on the segregant populations. The realized gain in seed/yield reached after one cycle of selection (C1) was 6.5 g, about 20% over the base population (C0). The expected gain from selection based on the superior 5% plants in C2 families was 25.5% and approached the realized gain. The result of this paper gives evidence to support that the seed yield can be improved by an adequate selection intensity and selection index can be very useful when it is faced with the improvement of several traits at the same time.  相似文献   
979.
Estimates of N2 fixation in segregating populations of bean plants based on 15N-isotope methods are technically demanding and expensive; therefore, indirect measures based on related traits including total seed N were used to select for improved N2 fixation and yield. In 1985, six populations of F2-derived F3 families resulting from six parental lines crossed to a common tester were grown in field trials on a low-N soil. In 1986, 25 selected half-sib families and two populations of full-sib F4 families were grown under similar conditions. Parents and a non-nodulating soybean line were included both years. Narrow sense (HNS) heritability estimates based on parent-offspring regressions ranged from 0.57 for total seed N to 0.39 for shoot biomass in one population, but were near zero for all measured traits in a second population. Among the criteria used to identify parental lines with superior potential for producing progenies with high total seed N, testcross population means combined with estimates of realized heritability were the most reliable. Selection of the best F3 families for total seed N resulted in F4 families with increased total seed N and higher seed yields, while seed protein percentage was unchanged. When plants are grown on low-N soils, selection for total seed N offers a useful alternative to selection for increased N2 fixation based on 15N-isotopic or total-N-difference method.  相似文献   
980.
Anther Culture Response in Perennial Ryegrass (Lolium perenne L.)   总被引:1,自引:0,他引:1  
20 diploid clones from 7 varieties, and 10 tetraploid clones from 3 varieties of Lolium perenne were tested in replicated anther culture experiments. Embryos or calluses, were obtained from all clones, and plants were regenerated from all clones except one. The total yield of plants (albino and green plants) ranged from 0 to 61 plants per 100 cultured anthers among genotypes, and there was a general tendency for tetraploic genotypes to be more responsive. Viable green plants were obtained from 5 diploid and 7 tetraploid clones representing 2 and 3 varieties, respectively. Their origin from reduced pollen was confirmed by a haploid chromosome number in some regenerants and by homozygosity for isozyme loci in spontaneously chromosome doubled plants produced from heterozygous diploid donor plants. A large number of the plants were successfully established in the soil. For most donor genotypes, green plants were rare exceptions, but two diploic clones consistently produced 2.3 and 3.8 green plants per 100 cultured anthers, respectively. Estimates of variance components from replicates with greenhouse and field-grown donor plants showed that genotypes accounted for about 73 per cent of the total variation in yield of embryos/calluses, while only 14—15 per cent of the total variation was due to replicates. Hence at present, emphasis should be placed on die selection of high-response genotypes in material of high agronomic potential.  相似文献   
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