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101.
K. Aitken J. Li L. Wang C. Qing Y. H. Fan P. Jackson 《Genetic Resources and Crop Evolution》2007,54(7):1395-1405
Erianthus rockii, a wild relative of sugarcane, is drought and cold tolerant, and both are potentially important agronomic traits to the sugarcane
industry worldwide. As such it is of interest as a source of parental germplasm to sugarcane breeders and is currently being
used in sugarcane introgression programs in both China and Australia. To date morphological characters have been used to verify
the putative hybrids produced. Two crosses were generated between two different Saccharum species and two E. rockii accessions. Over 400 AFLP markers were used to identify the intergeneric hybrid progeny as well as determine hybrid diversity.
Both crosses generated hybrids but efficiency levels were very different and are probably related to the different Saccharum parent used in each cross. Cross 1 was between a Saccharum officinarum and E. rockii and generated 100% hybrid progeny. Cross 2, however, was between a sugarcane hybrid (S. officinarum × Saccharum spontaneum) and E. rockii and only 10% of the progeny were intergeneric hybrids. Inheritance of markers in the progeny was analysed and for both crosses
there were equal numbers of markers from both parents indicating n + n transmission of chromosomes. This is the first verification of E. rockii hybrids with molecular markers. It may now be possible to exploit genes of value from E. rockii in sugarcane breeding programs. 相似文献
102.
Several Nicotiana species, their intergeneric sexual and somatic hybrids were compared for their in vitro growth rate and nicotine content. Cell yield on a dry weight basis and HPLC analysis of their nicotine content revealed a very high variation within each cell line from parental, sexual and somatic hybrids for the two traits analyzed. The trigeneríc sexual hybrids (N. rustica × N. debneyi) × N. tabacum and only two of the N. rustica × N. tabacum somatic hybrid lines show a positive heterosis in nicotine content in vitro The in vitro growth rate and nicotine content did not demonstrate a statistically significant correlation. 相似文献
103.
P. Devaux 《Plant Breeding》1987,98(3):215-219
The relative response to two-major techniques of producing haploids in barley – anther culture and the Hordeum bulbosyum method – were compared using seven F1 hybrids from a winter barley breeding programme. Both techniques were Applied to the same plants with the same number of replications. 358 viable green plants were obtained from 420 spikes ot donor plants used: 147 through anther culture and 211 through the H. bulbosum method. From the data analysis we found that the response to the two techniques was not significantly different, genotype effect and genotype × technique interaction were highly significant. The possibility of combining the two techniques in a doubled haploid production programme is discussed. 相似文献
104.
不同基因型玉米品种抗旱性田间鉴定研究 总被引:4,自引:0,他引:4
为研究不同品种玉米在干旱条件下的形态与产量性状、明确不同基因型玉米品种的抗旱性,采用产量抗旱指数为评价参数,分析各性状与参数间的关系,筛选出有效的综合评价指标,并对各品种的抗旱性进行分类。结果表明,干旱处理下玉米品种籽粒产量均明显低于正常处理,雌雄开花间隔增加,株高和穗位高降低,穗短小,秃尖多,穗粒数少,粒质量轻,最终导致产量下降。雌雄开花间隔、保绿性与产量抗旱指数之间呈极显著或显著相关。通过这些形态指标可鉴选出抗旱性好的品种。 相似文献
105.
The ultra-structure of mother and outer daughter scales of Lilium Oriental hybrid Sorbonne were studied using transmission electron microscope to examine the sub-cellular localization of starch and lip... 相似文献
106.
秦巴山区玉米杂交组合主要性状与产量间的灰色关联度分析 总被引:3,自引:0,他引:3
运用灰色系统理论中杂交组合灰色评判原理与方法,对60个玉米组合的产量和9个产量因素进行灰色关联分析及综合评判,以明确不同玉米杂交组合产量和产量构成因素之间的关系。结果表明:秦巴山区玉米杂交组合产量与主要农艺性状的关联度大小排序为穗粗>百粒重>穗长>穗位高>穗行数>行粒数>出子率>株高>秃顶长。组合46综合性状最好(G=0.881),组合52次之(G=0.861),组合54综合性状最差(G=0.552),综合评判结果与杂交组合在生产实际中表现基本一致。 相似文献
107.
不同玉米品种(系)田间抗蚜性的初步鉴定 总被引:2,自引:0,他引:2
采用蚜情指数法,初步鉴定了河南省4个主栽玉米品种和7个自交系的田间抗蚜性.结果表明,不同品种(系)的抗蚜性存在差异,4个主栽品种浚单20、郑单958、良玉88和先玉335对玉米蚜的抗性级别均在“中抗”以上,其中浚单20和郑单958的抗性最强,达“高抗”水平,其次是良玉88;7个自交系中昌7和昌7-2的抗蚜性最强,达“抗虫”或“高抗”水平,齐319的抗性最弱,为“高感”水平.本研究建立了利用抽雄期至灌浆期的蚜情指数代表玉米全生育期蚜情指数的抗蚜性鉴定方法,结果表明在驻马店和郑州两地的鉴定结论基本一致,说明这种方法是可行的. 相似文献
108.
《Scandinavian Journal of Forest Research》2012,27(1-4):15-26
The variance of general combining ability (GCA) and specific combining ability (SCA) for height and diameter growth were estimated from a 13 years old provenance hybridization study in Norway spruce. The GCA variance component for both height and diameter growth was significant, but there was no significant SCA variance. Hybrid progenies outperformed the progenies from stands, but this superiority was not interpreted as a provenance heterosis effect. Estimated family heritabilities for height and diameter growth were moderately high (0.40 for both traits). A consequence of the low SCA variance for Norway spruce may be that clonal testing should replace progeny testing for estimating GCA. 相似文献
109.
110.
Roberta Teta Elena Irollo Gerardo Della Sala Giuseppe Pirozzi Alfonso Mangoni Valeria Costantino 《Marine drugs》2013,11(11):4451-4463
An in-depth study of the secondary metabolites contained in the Caribbean sponge Smenospongia aurea led to the isolation of smenamide A (1) and B (2), hybrid peptide/polyketide compounds containing a dolapyrrolidinone unit. Their structures were elucidated using high-resolution ESI-MS/MS and homo- and heteronuclear 2D NMR experiments. Structures of smenamides suggested that they are products of the cyanobacterial metabolism, and 16S rRNA metagenomic analysis detected Synechococcus spongiarum as the only cyanobacterium present in S. aurea. Smenamides showed potent cytotoxic activity at nanomolar levels on lung cancer Calu-1 cells, which for compound 1 is exerted through a clear pro-apoptotic mechanism. This makes smenamides promising leads for antitumor drug design. 相似文献