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101.
Perry L Dickau R Zarrillo S Holst I Pearsall DM Piperno DR Berman MJ Cooke RG Rademaker K Ranere AJ Raymond JS Sandweiss DH Scaramelli F Tarble K Zeidler JA 《Science (New York, N.Y.)》2007,315(5814):986-988
Chili peppers (Capsicum spp.) are widely cultivated food plants that arose in the Americas and are now incorporated into cuisines worldwide. Here, we report a genus-specific starch morphotype that provides a means to identify chili peppers from archaeological contexts and trace both their domestication and dispersal. These starch microfossils have been found at seven sites dating from 6000 years before present to European contact and ranging from the Bahamas to southern Peru. The starch grain assemblages demonstrate that maize and chilies occurred together as an ancient and widespread Neotropical plant food complex that predates pottery in some regions. 相似文献
102.
Frank Ordon Jutta Ahlemeyer Kay Werner Wolfgang Köhler Wolfgang Friedt 《Euphytica》2005,146(1-2):21-28
Summary During the last decades extensive progress has been achieved in winter barley breeding with respect to both, yield and resistance
to fungal and viral diseases. This progress is mainly due to the efficient use of the genetic diversity present within high
yielding adapted cultivars and – with respect to resistance – to the extensive evaluation of genetic resources followed by
genetic analyses and introgression of respective genes by sexual recombination. Detailed knowledge on genetic diversity present
on the molecular level regarding specific traits as well as on the whole genome level may enhance barley breeding today by
facilitating efficient selection of parental lines and marker assisted selection procedures. In the present paper the state
of the art with respect to virus diseases, i.e. Barley mild mosaic virus, Barley yellow mosaic virus, and Barley yellow dwarf virus is briefly reviewed and first results on a project aiming on a genome wide estimation of genetic diversity which in combination
with data on yield and additional agronomic traits may facilitate the detection of marker trait associations and a more efficient
selection of parental genotypes are presented. By field tests of 49 two-rowed and 64 six-rowed winter barley cultivars the
genetic gain in yield for the period 1970–2003 was estimated at 54.6 kg ha−1 year−1 (r2 = 0.567) for the six-rowed cultivars and at 37.5 kg ha−1 year−1 (r2 = 0.621) for the two-rowed cultivars. Analysis of 30 SSRs revealed a non-homogenous allele distribution between two and six-rowed
cultivars and changes of allele frequencies in relation to the time of release. By PCoA a separation between two and six-rowed
cultivars was observed but no clear cut differentiation in relation to the time of release. In the two-rowed cultivars an
increase in genetic diversity (DI) from older to newly released cultivars was detected. 相似文献
103.
Stine Tuvesson Christophe Dayteg Per Hagberg Outi Manninen Pirjo Tanhuanpää Teija Tenhola-Roininen Elina Kiviharju Jens Weyen Jutta Förster Joerg Schondelmaier Julia Lafferty Marion Marn Andreas Fleck 《Euphytica》2007,158(3):305-312
The breeding companies and laboratories involved in this article cover a wide range of crops grown in the temperate climate
zone: small grain cereals, oilseed crops, forage crops, turf, vegetables and potato. Speed and efficiency are becoming increasingly
important in variety breeding and doubled haploids (DH) and genetic markers are important biotechnological tools to accelerate
materials to market. Collaborative research between universities, research institutions and breeding companies has resulted
in the routine use of DH technology and molecular markers in practical breeding of barley, wheat and rapeseed. DH populations
have been established not only for barley, wheat and rapeseed, but for rye, oat and triticale, where DH technology is less
developed. A driver here is the value of the crop e.g. although wheat is less responsive to DH production the value of the
end product makes the effort worthwhile. Simple and rapid DNA extraction methods used in high-throughput marker assisted selection
(MAS) systems are essential for routine use of markers. MAS is used both to monitor the presence of genes of interest and
also to monitor the genetic background. DH technology in forage, turf and vegetables is still in progress and the practical
use of markers in all crops is limited by access to trait linked markers. Collaboration and technology transfer with universities,
research institutions and breeding companies is essential for the improvement of both DH protocols in recalcitrant crops and
marker technology in all crops. 相似文献
104.
Jutta Krüger 《Euphytica》1994,77(1-2):1-6
Fifty-six populations of common bean (Phaseolus vulgaris L.) were grown in Pontevedra (Northwestern Spain) in four different environments in order to study their genetic diversity in 18 agronomical traits. All characters showed significant differences among populations, and most of them had significant genotype-environment interactions. Broad-sense heritability for this pool of characters ranged from 0.87 (seed length) to 0.12 (seed yield). Sixteen populations which deserve special attention because of their breeding value for earliness, yield, pod and seed size have been identified. 相似文献
105.
Bin Wu Vanessa Oesker Jutta Wiese Susann Malien Rolf Schmaljohann Johannes F. Imhoff 《Marine drugs》2014,12(4):1924-1938
A novel spirocyclic drimane coupled by two drimane fragment building blocks 2 and a new drimane 1 were identified in mycelia and culture broth of Stachybotrys sp. MF347. Their structures were established by spectroscopic means. This is the first example of spirocyclic drimane coupled by a spirodihydrobenzofuranlactam unit and a spirodihydroisobenzofuran unit; and the connecting position being N-C instead of an N and N connecting unit. Strain MF347 produced also the known spirocyclic drimanes stachybocin A (12) and stachybocin B (11) featured by two sesquiterpene-spirobenzofuran structural units connected by a lysine residue; the known spirocyclic drimanes chartarlactam O (5); chartarlactam K (6); F1839A (7); stachybotrylactam (8); stachybotramide (9); and 2α-acetoxystachybotrylactam acetate (10); as well as ilicicolin B (13), a known sesquiterpene. The relative configuration of two known spirobenzofuranlactams (3 and 4) was determined. All compounds were subjected to biological activity tests. The spirocyclic drimane 2, 11, and 12, as well as the sesquiterpene 13, exhibited antibacterial activity against the clinically relevant methicillin-resistant Staphylococcus aureus (MRSA). 相似文献
106.
Renate Dving Osvik Richard Andre Ingebrigtsen Maria Fredrika Norrbin Jeanette Hammer Andersen Hans Christian Eilertsen Espen Holst Hansen 《Marine drugs》2021,19(2)
“One strain many compounds” (OSMAC) based approaches have been widely used in the search for bioactive compounds. Introducing stress factors like nutrient limitation, UV-light or cocultivation with competing organisms has successfully been used in prokaryote cultivation. It is known that diatom physiology is affected by changed cultivation conditions such as temperature, nutrient concentration and light conditions. Cocultivation, though, is less explored. Hence, we wanted to investigate whether grazing pressure can affect the metabolome of the marine diatom Porosira glacialis, and if the stress reaction could be detected as changes in bioactivity. P. glacialis cultures were mass cultivated in large volume bioreactor (6000 L), first as a monoculture and then as a coculture with live zooplankton. Extracts of the diatom biomass were screened in a selection of bioactivity assays: inhibition of biofilm formation, antibacterial and cell viability assay on human cells. Bioactivity was found in all bioassays performed. The viability assay towards normal lung fibroblasts revealed that P. glacialis had higher bioactivity when cocultivated with zooplankton than in monoculture. Cocultivation with diatoms had no noticeable effect on the activity against biofilm formation or bacterial growth. The metabolic profiles were analyzed showing the differences in diatom metabolomes between the two culture conditions. The experiment demonstrates that grazing stress affects the biochemistry of P. glacialis and thus represents a potential tool in the OSMAC toolkit. 相似文献
107.
Lignin is a heterogenous phenolic polymer that plays crucial roles in the development and physiology of vascular plants. However,
it needs to be removed from cellulose by toxic and energy-requiring processes for the production of high-quality paper. Therefore,
a major biotechnological challenge is to obtain transgenic trees with modified lignin to improve the quality of wood for paper
making. Here, we review the results obtained by alterating the expression of genes of the monolignol biosynthesis pathway
in trees and the effect of these modifications on the lignin polymer and on pulping. The data reported show that lignin engineering
is a promising strategy to improve wood quality for the pulp and paper industry.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
108.
109.
Nitzsche A Tokalov SV Gutzeit HO Ludwig-Müller J 《Journal of agricultural and food chemistry》2004,52(10):2915-2923
Cell cultures of lavender (Lavandula officinalis) were analyzed for the metabolite profile under normal growth conditions and under stress as well as after jasmonic acid treatment. The main compound synthesized was rosmarinic acid, which was also secreted into the culture medium. Different solvent extraction methods at different pH values altered the profile slightly. Anoxic stress induced the synthesis of a cinnamic acid derivative, which was identified as caffeic acid by gas chromatography-mass spectrometry. Caffeic acid was also induced after treatment of the cell cultures with jasmonic acid. Although the antioxidative activity of both compounds, rosmarinic acid and caffeic acid, was confirmed in an assay using 2,2-diphenyl-1-picrylhydrazyl (DPPH), it was demonstrated that both substances have a low cytotoxic potential in vitro using acute myeloid leukemia (HL-60) cells. The potential of the system for finding new bioactive compounds is discussed. 相似文献
110.