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21.
文章分析传统岭南庭园的造园艺术在当代热带庭园设计中的运用和发展,重点对空间渗透交流、视线与空间序列、花木营造等方面进行分析,找寻其中的历史情结,以期为中国当代热带庭园的传承与创新提供一些参考。 相似文献
22.
猎鹰是柯尔克孜人最常见、最有趣的一种民间文化习俗。具有悠久文化底蕴,是早已深深根植于柯尔克孜民族血脉之中的民族体育项目,如今依然占据着无法替代的地位。他反映出与这个民族的曾经的生活、生产方式。对其进行挖掘,尤其对其活形态文化特征进行研究不仅有利于丰富柯尔克孜体育文化内涵,并且有利于其民族传统体育的推广及保护。 相似文献
23.
随着表观遗传学的兴起,获得性遗传研究开始复兴,现已发现大量获得性遗传现象,但获得性遗传作为一种进化机制仍没有得到广泛认同,其原因在于获得性(表型)遗传如何固化为基因型的研究没有取得进展.通过综合分析表观遗传学所揭示的获得性遗传事实,提出一种获得性遗传的表观遗传学机制,给出获得性(表型)转化为基因型的可能路径. 相似文献
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The inheritance of the sterility maintenance ability was studied for three types of CMS lines (Zhenshan97A, XieqingzaoA and Ⅱ-32A) and several lines in indica rice. The result showed that the abilities to keep the male sterility of the maintainer lines strengthened obviously with the progressive backcrossing. The critical stage to maintain the sterility of CMS lines happened usually in BC5-6 generation. The selection of the recurrent parent gave an obvious influence on the pollen fertility distribution of the later generations. The author has discussed ways of improving of the maintainer lines. 相似文献
26.
甘蓝型油菜小孢子培养胚发生能力的遗传分析 总被引:4,自引:0,他引:4
用 4× 4完全双列杂交研究了甘蓝型油菜小孢子培养胚状体发生能力的遗传规律。结果表明 :多数F1的胚产量与具高胚发生能力的亲本相近 ,部分F1的胚产量与双亲中亲值接近。胚状体发生能力主要由基因的加性效应控制。高胚发生能力由显性核基因控制。广义和狭义遗传力分别为 97 2 %和 81 1%。由Lisandra(高胚发生能 )×Kamikita(低胚发生能 )的F2 群体胚发生数的分离结果得出小孢子胚状体发生能力由具加性效应特点的两个基因位点控制 相似文献
27.
Most of the cytoplasmic-nuclear male-sterile (CMS) lines of soybean were developed only from a limited cytoplasm sources and performed not as good as required in hybrid seed production, therefore, to explore new male-sterile cytoplasm sources should be one of the effective ways to improve the pollination and hybridization for a better pod-set in utilization of heterosis of soybeans. In the present study, total 80 crosses between 70 cultivated and annual wild soybean accessions and three maintainers (N2899, N21249, and N23998) of NJCMS1A were made for detecting potential new sources with male-sterile cytoplasm. The results showed that in addition to the crosses with N8855.1 (the cytoplasm donor parent of NJCMS1A) and its derived line NG99-893 as cytoplasm parent, there appeared three crosses, including N21566 × N21249 and N23168 × N21249, with male-sterile plants in their progenies. According to the male fertility performance of backcrosses and reciprocal crosses with the tester N21249, the landrace N21566 and annual wild soybean accession N23168 were further confirmed to have male-sterile cytoplasm. Accordingly, it was understood that the source with male-sterile cytoplasm in soybean gene pool might be not occasional. The results also showed that the genetic system of male sterility of the newly found cytoplasm source N21566 was different from the old cytoplasm source N8855.1, while N23168 was to be further studied. Based on the above results, the derived male-sterile plants from [(N21566 × N21249) F1 × N21249] BC1F1 were back-crossed with the recurrent parent N21249 for five successive times, and a new CMS line and its maintainer line, designated as NJCMS3A and NJCMS3B, respectively, were obtained. NJCMS3A had normal female fertility and stable male sterility. Its microspore abortion was mainly at middle uninucleate stage, earlier than that of NJCMS1A and NJCMS2A. The male fertility of F1s between NJCMS3A and 20 pollen parents showed that 7 accessions could restore its male fertility and other 13 could maintain its male sterility. The male sterility of NJCMS3A and its restoration were controlled by one pair of gametophyte male-sterile gene according to male fertility segregation of crosses between NJCMS3A and three restorers. The nuclear gene(s) of male sterility in NJCMS3A appeared different from the previously reported CMS lines, NJCMS1A and NJCMS2A. The development of NJCMS3A demonstrated the feasibility to discover new CMS system through choosing maintainers with suitable nuclear background. 相似文献
28.
29.
Tartary buckwheat (Fagopyrum tataricum) is a highly nutritious crop that is widely grown in Asia, but the flour contains a large portion of the hull if it is ground
with industrial processing since the hull is very hard to remove as it adheres to the testa layer of the groat. Rice-Tartary,
a particular type of Tartary buckwheat, has seeds with a loose hull and the presence of splits on the sides of the seeds that
make dehulling easily. The present study reports on the first attempt of crop improvement in Tartary buckwheat breeding through
hybridization. Hybrids were obtained by hybridization of crosses between Tartary buckwheat and Rice-Tartary. Additional crosses
were made among selected progenies of these crosses. Based on progeny analysis of the F1, F2, and F3, the character of Rice-Tartary, as exhibited as the presence of splits on the sides of the seeds, is controlled by one gene
which is homozygous recessive. A Tartary buckwheat breeding program has been conducted for 6 years based on these crosses.
Advanced lines with easy dehull and yield potential are at the stage of ready for yield trials. Production of easy dehulling
Tartary buckwheat in the future could boost Canada’s domestic and international markets. 相似文献
30.
Raquel Sánchez-Pérez Encarnación Ortega Henri Duval Pedro Martínez-Gómez Federico Dicenta 《Euphytica》2007,155(3):381-391
The inheritance of 16 important agronomic traits and its relationship were studied for four years in a population of 167 almond
[P. dulcis (Mill.) D.A. Webb] seedlings obtained from a cross between the French selection ‘R1000’ (‘Tardy Nonpareil’ × ‘Tuono’) and
the Spanish cultivar ‘Desmayo Largueta’. For some traits (blooming and leafing date) descendants segregated between the value
of both progenitors, meanwhile for others the mean of the offspring was lower (bloom density, productivity and ripening date)
or higher (in-shell/kernel ratio and double kernels). As expected, kernel bitterness and self-incompatibility behaved as monogenic
traits. Some important correlations between traits were detected. The implications of the transmission and the correlation
of these traits in the breeding programmes are discussed. 相似文献