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931.
Most fenugreek, Trigonella foenum-graecum L. suitable for western Canada exhibit an indeterminate growth habit and take about 120 days to produce a good proportion
of high quality seed. Late maturity is a major inconvenience for seed producers in temperate climates prevalent in this region
where plants must mature within a much shorter growing season. The objective of this study was to develop early maturing fenugreek
mutants with a determinate growth habit to ensure uniform maturity within the 100 frost free days available on the Canadian
prairies. Seeds from Tristar Fenugreek, a forage cultivar developed for production in western Canada, were treated with 10–300 mM
ethyl methane sulfonate (EMS) for 2–24 h and plants were selected for determinate growth habit, early maturity and high seed
yield. This mutation breeding approach has detected new breeding material exhibiting early seed maturity coupled with high
seed yield, seed quality and determinate growth habit. Successful development of useful mutants in fenugreek was reported
before, but this is the first report on successful use of mutation breeding for improvement in quantitative traits in this
crop. 相似文献
932.
Isatis tinctoria L. (woad) is a dye plant whose cultivation is increasing because of its adaptability to marginal conditions and increasing
demand for natural products. Suitable breeding schemes need to be set up in order to obtain woad varieties for each proposed
environment. Presently, no data about the reproductive system are available. The effects of selfing and crossing on setting
and progeny vigour were assessed. Results showed the existence of an outcrossing system in I. tinctoria. Obligate self-pollinated plants produced fewer siliques (7.1 g per plant) with lower weight (6.0 mg) and lower seed germinability
(8.2%) than outcrossing plants (44.1 g, 8.0 mg and 46.0% for each character, respectively). Self-pollinated progenies also
generally showed lower vigour than outcrossing progenies. 相似文献
933.
Glauco Vieira Miranda Leandro Vagno de Souza João Carlos Cardoso Galvão Lauro José Moreira Guimarães Aurélio Vaz de Melo Izabel Cristina dos Santos 《Euphytica》2008,162(3):431-440
The development of successful advanced lines and cultivars in maize is dependent on parental selection and assignment to defined
heterotic groups. So, the objectives of this study were to evaluate genetic variability and identify heterotic groups among
Brazilian popcorn varieties. Thus, diallel crosses of advanced generations of the popcorn hybrids, IAC 112 and Zélia, and
of three open-pollinated popcorn varieties, RS 20, Branco, and SAM were performed. Ten hybrid combinations, the five parents,
and five check treatments were arranged in a block design with four replicates in two tropical-zone locations (CWb climate).
Both additive and non-additive effects were important for grain yield, plant height, ear height, and husk cover. For popping
expansion, only the additive effects were important. Hybrid combinations between the local variety (Branco) and F2 populations (IAC 112 and Zelia) resulted in the third and fourth highest values for popping expansion. The best grain yields
were obtained with hybrid combinations involving SAM. Cultivars Zélia, IAC 112, and RS 20 increased popping expansion, whereas
cultivar Branco increased grain yield of hybrid combinations. The following conclusions may be drawn: Brazilian popcorn populations
have reduced heterosis and genetic variability to popping expansion in relation commercial cultivars; there is genetic variability
among Brazilian popcorn populations that allows the exploitation of additive and non-additive effects for grain yield; it
is possible to increase grain yield by using local varieties; but it would be difficult to obtain commercial hybrids from
local varieties because they have poor performance for popping expansion. 相似文献
934.
Maria Suely Pagliarini Claudicéia Risso-Pascotto Alice Maria de Souza-Kaneshima Cacilda Borges do Valle 《Euphytica》2008,164(1):181-187
Sexuality is correlated with diploidy and apomixis with polyploidy in the Brachiaria genus. Brachiaria ruziziensis is a key species in Brachiaria breeding due to its obligate sexuality and intrinsic agronomic qualities. Interspecific crosses in the genus became feasible
only when a few diploid accessions of B. ruziziensis were artificially tetraploidized and remained sexual. Hybridization has been done since, using natural tetraploid apomictic
accessions of B. brizantha or B. decumbens as pollen donors. Twenty two accessions of B.
ruziziensis from the Embrapa Beef Cattle germplasm collection (Campo Grande, MS, Brazil) were cytologically analyzed: 16 are natural
diploids (2n = 2x = 18) and six are artificially induced tetraploids (2n = 4x = 36). The meiotic behavior in the 16 diploid accessions varied. The mean of meiotic abnormalities per accession ranged from
zero to 24.46%. Meiotic behavior in the induced tetraploid accessions also varied with the mean of meiotic abnormalities ranging
from 5.20% to 54.71%. The most common abnormalities observed in both the diploid and the tetraploid accessions, were those
related to irregular chromosome segregation. In one tetraploid accession, with a high frequency of those, other irregularities
involving chromosome orientation at metaphase plate and chromosome convergence to the poles, a meiotic mutation known as divergent spindle, were recorded. Meiotic behavior should be considered in selecting potential genitors for breeding. 相似文献
935.
利用转基因牛生产重组人乳铁蛋白研究 总被引:6,自引:0,他引:6
[目的]研究利用转基因牛生产重组人乳铁蛋白,为利用转基因动物生产药用或食用蛋白提供依据。[方法]对已获得的人乳铁蛋白转基因牛进行人工催乳,用乳成分分析仪分析了转基因对乳汁的影响,并利用放免法检测了重组人乳铁蛋白在转基因牛乳中的表达。[结果]重组人乳铁蛋白在牛乳中获得了高效表达,表达水平为(3.429±0.417)mg/ml。通过转基因牛乳的乳成分分析发现,转基因牛乳与常乳在乳脂、总蛋白、乳糖和干物质的含量上没有明显变化。[结论]重组人乳铁蛋白在转基因牛乳中获得了高效表达,为大规模生产重组人乳铁蛋白奠定了基础。 相似文献
936.
杂交大豆昆虫传粉及制种技术研究进展 总被引:7,自引:0,他引:7
经过科学家的共同努力,吉林省农科院于2002年审定了世界上第1个大豆杂交种杂交豆1号,并于2006年审定了第2个大豆杂交种。从2000年开始,在封闭及开放条件下,利用苜蓿切叶蜂、蜜蜂、花蓟马等昆虫媒体为大豆传粉,进行不育系繁育及杂交种制种技术的探讨。已经实现在网室内利用蜜蜂及切叶蜂传粉,配制大豆杂交组合和生产小批量杂交种子,不育系结实率达到55.9%~100%;开放条件下,在干旱、有灌溉条件的地区,利用蜜蜂及苜蓿切叶蜂传粉,不育系结实率达到50%~80%,制种产量获得了较理想的结果。吉林省农科院在吉林省西部及内蒙古东部干旱地区,建立了制种基地,进行了较大面积的大豆不育系扩繁及杂交种制种试验,制种技术基本成熟。 相似文献
937.
938.
Franziska Löschenberger Andreas Fleck Heinrich Grausgruber Herbert Hetzendorfer Gerhard Hof Julia Lafferty Marion Marn Anton Neumayer Georg Pfaffinger Johann Birschitzky 《Euphytica》2008,163(3):469-480
Breeding for organic agriculture (BFOA) is a strategy for a commercial breeding company based on the exploitation of the frequently
observed high correlation for many traits between conventional, low input (LI) and organic agriculture (ORG). Indirect selection
under LI can be useful to roughly divide the germplasm into the genotypes better adapted to high input and those better adapted
to LI or ORG conditions. BFOA is an evolving process, in which two methods are currently applied: early generations are either
selected following the pedigree system under LI, or grown as bulk populations on ORG fields. In the latter case the system
switches to LI after individual ear selection under ORG conditions. In both methods, the first replicated yield trial is grown
parallel under ORG and LI. Subsequently, the genotypes are grouped into conventional or ORG advanced trial series. The BFOA
strategy allows that the larger genetic variability of both the organic and conventional gene pool can be exploited in the
selection for ORG. Hitherto, seven winter wheat varieties were released in Austria after exclusive organic VCU testing. 相似文献
939.
New Varieties of Populus tomentosa Carr. and Breeding Techniques 总被引:2,自引:0,他引:2
ZHOU Hui-ru Virescence Maintenance Management Office of Xuchang City Henan Province Xuchang 《(《农业科学与技术》)编辑部》2008,(2)
The main morphological characteristics,producing area and growth characteristics of sixteen new varieties of Chinese white poplar (Populus tomentosa Carr.) are reported,aiming at providing reference for breeding and extension of new varieties. 相似文献
940.