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51.
52.
During the excavation of an early medieval lakeside settlement at Fonyód-Bélatelep, Balaton (7th-9th century A.D.), remains of cultivated and wild plants were found in the culture layer. The main cereal crops of the Avar culture were Hordeum, Triticum and Secale. Panicum also played an important role. In addition to the cereals, 13 species of fruit trees were present. It appears that fruit cultivation survived from Roman times into the early medieval period. 相似文献
53.
对栽培大麦(HordeumvulgareL.品种“Arupo”)与纤毛鹅观草(Roegneriaciliaris(Trin.)Nevski)属间杂种后代F5和回交后代BC1F4(以“Arupo”作回交亲本)的不同类型株系与其双亲的幼根、幼芽、幼穗、幼嫩籽粒分别进行了酯酶、过氧化物酶同工酶分析。结果F5和BC1F4各株系的酯酶同工酶、过氧化物酶同工酶酶谱具有母本“Arupo”全部或绝大多数酶带,父本R.ciliaris的1~3条酶带和数量不等的双亲所没有的新酶带,也出现酶带的减少。结果表明,纤毛鹅观草的遗传物质已稳定地遗传给了其自交和回交后代。酶谱变异与植株习性出现一定程度的关联。由于在不同时期内结构基因的表达起不同作用,因此,在用同工酶分析法鉴定易位系时,最好不同的器官采用不同的酶类或一种同工酶多时期连续分析。 相似文献
54.
本文报导了君子兰(Clivia miniata)软腐病二株病原体的分离及确定;鉴定了病原体的分类地位,一株为链球菌属的一个新种,定名为君子兰链球菌(Streptococcus miniatus Zhou,Ping et al shao sp.nov),另一株为环状芽孢杆菌(Bacillus subtilis);并对其二病原体的侵染途径与致病规律进行了研究。 相似文献
55.
Ishii T. Terachi T. Mori N. Tsunewaki K. 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1993,86(1):88-96
Summary Restriction fragment length polymorphisms of chloroplast (ct), mitochondrial (mt) and nuclear DNA were investigated using eight cultivars of Oryza sativa and two cultivars of O. glaberrima. Relative variability in the nuclear and cytoplasmic genomes was estimated by a common measure, genetic distance. Based on the average genetic distances among ten cultivars for each genome, the evolutionary variabilities of the mitochondrial and nuclear genomes were found to be almost the same, whereas the variability of the chloroplast genome was less than half that of the other two genomes. Cluster analyses on ct and mt DNA variations revealed that chloroplast and mitochondrial genomes were conservative within a taxon and that their differentiations were well-paralleled with respect to each other. For nuclear DNA variation, an array of different degrees of differentiation was observed in O. sativa, in contrast with little variation in O. glaberrima. As a whole, differentiation between O. sativa and O. glaberrima was clearly observed in all three genomes. In O. sativa, no notable difference was found between the cultivars Japonica and Javanica, whereas a large differentiation was noticed between Japonica (including Javanica) and Indica. In all three genomes, the average genetic distances within Indica were much larger than those within Japonica (including Javanica), and almost similar between Japonica (including Javanica) and Indica. These facts indicate that differentiation in O. sativa was due mainly to Indica. 相似文献
56.
Z. Li W. K. Heneen 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,99(3-4):694-704
It has been proposed that both complete and partial separation of the parental genomes during mitosis and meiosis occurs in
the intergeneric hybrids between Orychophragmus violaceus (2n=24) and the three cultivated Brassica tetraploids (B. napus, B. carinata and B. juncea). The hypothesis has been that this and the variations in chromosome numbers of these hybrids and their progenies result
from the different roles of the A, B and C genomes originating from Brassica. To test this hypothesis, we produced hybrids between O. violaceus and the cultivated Brassica diploids. The hybrids with B. oleracea (2n=18, CC) had an intermediate morphology, but their petals were purple like those of O. violaceus. They were sterile and had the expected chromosome number (2n=21) in their mitotic and meiotic cells. The hybrid with B. campestris (2n=20, AA) was morphologically intermediate, except for its partial fertility and its yellow petals, which were similar to
those of B. campestris. It was mixoploid (2n=23–42), and cells with 2n=34 were most frequent. Partial separation of parental genomes during mitosis,
leading to the addition of O. violaceus chromosomes to the B. campestris complement, was proposed to explain the findings in the mitotic and meiotic cells of the hybrid and its progeny. In crosses
with B. nigra (2n=16, BB), the majority of the F1 plants were of the maternal type (2n=16), a small fraction had B. nigra morphology but were mixoploids (2n=16–18), predominantly with 2n=16 cells and three plants, each with a specific morphology,
were mixoploids consisting of cells with varying ranges of chromosome numbers (2n=17–26, 11–17 and 14–17). The origin of these
different types of plants was inferred to be a result of the complete and partial separation of parental genomes and the loss
of O. violaceus chromosomes. Our findings in the three crosses suggest that the A genome was more influential than the C genome with respect
to complete genome separation during mitosis and meiosis of the hybrids with B. napus. Possible complete and partial genome separation during mitotic divisions of the hybrids with B. carinata was mainly attributed to the role of the B genome. The combined roles of the A and B genomes would thus contribute to the
most variable chromosome numbers of mitotic and meiotic cells in the hybrids with B. juncea and their progenies. The possible cytological mechanisms pertaining to these hybrids and the potential of genome separation
in the production of Brassica aneuploids and homozygous plants are discussed.
Received: 8 February 1998 / Accepted: 12 March 1999 相似文献
57.
The E. coli beta-glucuronidase (GUS) gene was used in gene expression experiments with the protoplasts isolated from immature cotyledons of soybean (Glycine max L.). Transient expression of GUS gene could be detected in 1—6 days after DNA incorporation into soybean protoplasts by using a fluorogenic substrate MUG. Stable transformation was observed by histochemical localization with the use of a substrase X-Gluc. Some factors such as PEG toxicity and protoplast stability affecting PEG-mediated transformation were discussed. 相似文献
58.
59.
Helmut Kroll 《Vegetation History and Archaeobotany》2000,9(1):31-68
Publications on archaeological remains of cultivated plants have been collected, mainly from 1998, with some earlier ones, and some from 1999, A list is given of the finds according to taxon, country, site, and age 相似文献
60.
以黄淮海生态区181份栽培大豆与32份野生大豆为材料,采用高效液相色谱法测定其籽粒异黄酮及组分含量,分析该地区大豆籽粒异黄酮含量遗传变异,遴选高异黄酮特异种质,为相关基因克隆表达、RIL群体构建和专用型品种选育提供资源。结果表明,供试栽培大豆异黄酮含量在1462.6-6115.5 μg/g,平均为3558.2 μg/g,最大差异可达4.2倍;供试野生大豆异黄酮含量在3896.1-7440.4 μg/g,平均为5182.4 μg/g,最大差异可达1.9倍。可见,黄淮海生态区大豆资源异黄酮及组分含量存在较大遗传变异,且野生大豆异黄酮平均含量显著高于栽培大豆。从供试资源中遴选出异黄酮含量超过6000 μg/g特异种质4份(超过7000 μg/g种质1份)。 相似文献