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101.
贵州地处亚热带湿润季风气候区,水热条件比较优越,植物资源丰富,是天然的植物种质资源库。我们通过实验研究筛选出小黄花茶(Camellia luteoflora)、贵州苏铁(Cycas guizhouensis)、贵州槭(Acer guizhouense)等20种重要野生观赏植物,对其植物种质资源的原产地及其生态环境、资源价值、资源现状、植物引种栽培与利用评价等进行了广泛的调查分析和试验研究,并从中选择了10种植物开展种苗繁殖和扩大栽培的试验研究。通过研究,提出了对野生珍稀植物的开发利用一定要在这些植物种质资源已经得到有效保护的前提下进行,只有这样才能保存更多更好的优良遗传基因,建立起植物种质资源基因库,为开发新品种提供资源利用,最终实现其可持续性发展,变资源优势为经济优势。 相似文献
102.
采用自行研制的可调参数式行星球磨机对野生黑木耳进行了超微粉碎试验研究。对野生黑木耳进行精细加工,为开发出富含野生黑木耳超微粉的各种食品提供条件。试验采用5因素二次回归正交旋转组合试验设计的方法,建立了试验因素与试验指标间影响关系的数学模型,通过优化计算得到野生黑木耳超微粉碎的最佳工艺参数为:公转盘转速为574r/min,粉碎时间为4.2h,球料比为5,磨筒倾角为69o,填充率为23%,理论最佳颗粒粒径为3.9μm,实验值为4.12 ̄7.79,与理论最佳值基本一致,因此试验得出的数学模型可靠。同时进行了不同细度黑木耳粉的动物喂养实验,结果表明,黑木耳超微粉在净消化率、生物学价值、净利用率和功效比值方面均显著优于黑木耳粗粉和黑木耳细粉,对黑木耳进行超微粉碎具有实际意义。 相似文献
103.
Summary Sugar beet is a relatively young crop, which supposedly has a narrow genetic base. Natural variation occurring in primitive beet varieties and in wild Beta species has been used for breeding sugar beet. This paper reviews information on desirable characteristics in Beta germplasm and the attempts made for the introgression of such characters into commercial breeding material. After an introduction on the availability of germplasm and the possibilities of hybridisation, attention is focussed on the mating system (especially male sterility), on morphological and physiological characteristics, including yield and sugar content, and on resistances to diseases and pests. 相似文献
104.
Race-specificity of temperature-sensitive genes for resistance to Puccinia striiformis in Triticum dicoccoides 总被引:1,自引:0,他引:1
Summary Twenty-four entries of wild emmer possessing temperature-sensitive genes for resistance to yellow rust were studied in the seedling stage, at two temperature-profiles, with 15 pathogenic races from 11 countries in South America, Africa, Asia and Europe. It was shown that the majority of the resistance genes in these wild emmer entries were race-specific. In most of these entries a more resistant reaction was displayed at the higher temperature-profile; however in three entries a shift in reaction towards resistance was observed with certain races but towards susceptibility with some of the other races, suggesting that two different kinds of temperature-sensitive genes were involved in each of these entries. The similarity of temperature-sensitive genes occurring in wild emmer and in cultivated wheat is discussed. 相似文献
105.
M. T. Jackson J. G. Hawkes Beatrice S Male-Kayiwa N. W. M. Wanyera 《Plant Breeding》1988,101(4):261-268
Screening for resistance to the potato cyst nematode, Globodera pallida, in potatoes from. Bolivia, was carried out in 1983 and 1984, using a mixture of four nematode populations representing pathotypes Pa1, Pa2 and Pa3 From the 66 accessions of 17 species and subspecies evaluated, highly resistant genotypes were identified in 21 accessions from seven species. All had Pf/Pi values of 2 or less, whereas the susceptible control, Solanum tuberosum cv. ‘Disiree’ had Pf/Pi values of more than 2G in both tests. Two diploid wild species, S. brevicaule and S. leptophyes, showed the best resistant. The geographical distributional of resistant populations and the evolution of resistance in wild potato populations are discussed. 相似文献
106.
Summary The regular meiotic behaviour of the cultivated oat Avena sativa (2n=6x=42) is genetically controlled. The factors which control the diploid-like meiotic behaviour also restrict the amount of pairing that occurs between alien chromosomes and their homoeologues in A.sativa, and hence increases the difficulties of introducing desirable variation from wild species into the cultivated oat. A genotype of the diploid species A.longiglumis which interferes with the regular meiotic behaviour of A. sativa can be used to induce pairing between alien chromosomes and their corresponding chromosomes in A. sativa. Using this procedure the dominant gene conferring mildew resistance has been transferred from the tetraploid weed species A. barbata into the cultivated oat. 相似文献
107.
Eviatar Nevo Avigdor Beiles Yitzchak Gutterman Nurith Storch Diane Kaplan 《Euphytica》1984,33(3):717-735
Summary Populations of wild emmer wheat, Triticum dicoccoides, in Israel, originating from diverse habitats, and tested earlier for allozyme (Nevo et al., 1982) and disease resistance polymorphisms (Moseman et al., 1983a, 1983b; Nevo et al., 1984a, 1984b), were compared and contrasted for performance in agronomically important phenotypic traits. The traits compared involved 10 variables comparing germination, earliness, biomass and yield variables. The field experiments were conducted in 1980, 1981 and 1982 in two relatively standardized and contrasting environments: mesic (Mount Carmel, Haifa) and xeric (Acedat Farm, and Sede Boqer, in the northern Negev desert). The experimental design involved 12 population quadrangles at Avedat Farm in 1980, and rows of randomized genotypes of five populations in both Haifa and Sede Boqer in 1981 and 1982.The results indicate that the characters studied are partly genetically determined. Striking genetic variation was found between and, at least in some characters, also within populations in each site, whereas remarkable environmental variation including genetic-environmental interaction was found between the mesic and the xeric sites. We conclude that natural populations of wild emmer wheat in Israel vary not only in genetic polymorphisms of allozymes and disease resistance, but also in quantitative traits of agronomic importance. These traits are economically significant and should be conserved and utilized in wheat crop improvement. 相似文献
108.
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110.
Chloroplast DNA variation in 96 Prunus avium L. cultivars was assessed and compared with the results of a previous study of cpDNA diversity in 23 wild populations of the species. The polymerase chain reaction‐restriction fragment length polymorphism method was used in these studies. Approximately 9% of the chloroplast genome was analyzed, using five universal primer pairs and three restriction enzymes. Ten polymorphic fragments were common to both the wild and sweet cherry; eight polymorphic fragments were found only in the wild cherry. In the cultivars, all mutations were small (5‐30 bp) indels. In the wild populations, a point mutation was also detected in addition to indels. The mutational combinations revealed three haplotypes in the cultivars, which are the main haplotypes in the wild cherry populations. Chloroplast DNA diversity in wild cherry is higher (16 haplotypes) than in sweet cherry cultivars (three haplotypes). The probable wild origin of the sweet cherry cultivars in the maternal line, on the basis of haplotypic similarity, was discussed. 相似文献