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G. Csanádi J. Vollmann G. Stift T. Lelley 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2001,103(6-7):912-919
This study identified QTLs influencing seed quality characters in a cross of two early maturing soybean (Glycine max [L.] Merr.) cultivars (Ma.Belle and Proto) adapted to the short growing seasons of Central Europe. A molecular linkage map
was constructed by using 113 SSR, 6 RAPD and 1 RFLP markers segregating in 82 individuals of an F2 population. The map consists of 23 linkage groups and corresponds wellto previously published soybean maps. Using phenotypic
data of the F2-derived lines grown in five environments, four markers for protein content, three for oil content and eight for seed weight
were identified. Four from fifteen seed quality QTL-regions identified in the present study were also found by other authors.
Markers associated with seed weight QTLs were consistent across all environments and proved to have effects large enough to
be useful in a marker-assisted breeding program, whereas protein and oil QTLs showed environmental interactions.
Received: 9 October 2000 / Accepted: 26 February 2001 相似文献
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The relationship between biocontrol activity of Pseudomonas putida strain N1R against Pythium ultimum on pea and soybean seeds and the reduction in ethanol evolution by imbibed seeds was investigated under different treatment conditions, including temperature and numbers of seed‐applied cells of the bacterium. Treatment with strain N1R increased emergence at all temperatures, except for soybean at 12 °C and reduced ethanol concentration in the spermosphere of imbibed seeds at several temperatures. The concentration of bacterial cells in the seed treatment suspension also significantly affected biocontrol efficiency and reduced ethanol production, especially in pea seeds. In contrast, the duration (0–7 h) of submergence of seeds in bacterial suspension had little effect on biocontrol activity of N1R, although submergence of soybean seeds reduced their emergence even in the absence of the pathogen or biocontrol agent. Competition for seed‐derived compounds, including ethanol, is suggested to be one possible mechanism of biocontrol of Pythium by strain N1R, which is not known to produce antifungal antibiotics. 相似文献
86.
Kinetic parameters of nitrate uptake by different catch crop species: effects of low temperatures or previous nitrate starvation 总被引:8,自引:0,他引:8
The pollution of aquifers by NO?3 in temperate environments is aggravated by farming practices that leave the ground bare during winter. The use of catch crops during this time may decrease nitrate loss from the soil. Nitrate uptake by several catch crop species (Brassica napus L., Sinapis alba L., Brassica rapa L., Raphanus sativus L., Trifolium alexandrinum L., Trifolium incarnatum L., Phacelia tanacetifolia Benth., Lolium perenne L., Lolium multiflorum Lam. and Secale cereale L.) was here studied in relation to transpiration rate and low temperatures applied to the whole plant or to roots only. The Michaelis constant (Km), maximum uptake rate (Vmax), time of induction and contributions of inducible and constitutive mechanisms were estimated from measurements of NO?3 depletion in the uptake medium. There were large differences between species, with Km (μM) values ranging between 5.12 ± 0.64 (Trifolium incarnatum) and 36.4 ± 1.97 (Lolium perenne). Maximum NO?3 uptake rates expressed per unit root weight were influenced by ageing, temperature and previous NO?3 nutrition. They were also closely correlated with water flow through the roots and with shoot/root ratio of these species. The combined results from all species and treatments showed that Vmax increased with shoot/root ratio, suggesting a regulatory role for the shoots in NO?3 uptake. Overall, the results showed a great diversity in NO?3 uptake characteristics between species in terms of kinetic parameters, contribution of the constitutive system (100% of total uptake in ryegrass, nil in Fabaceae) and time of induction. 相似文献
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After a 2 h exposure of intact soybean nodules to high concentrations of NaCl (100mol m?3) or oxygen (8OkPa O2), morphometric computations carried out using an image analysis technique on semi-thin sections showed that both treatments induced a decrease in the area of the inner-cortex cells, which were then characterized by a tangential elongation. In contrast, no significant change in area occurred in the middle-cortex cells although their elongation decreased. Electron microscopic observations showed that in the inner-cortex cells changes included the presence of wall infoldings, an enlarged periplasmic space and a lobate nucleus whose chromatin distribution differed from that of the control. Structural changes also occurred in the endoplasmic reticulum, microbodies, mitochondria and plastids. From several of these changes, which are similar to those noted in osmocontractil cells in response to external stimuli, it can be hypothesized that the inner cortex may provide a potential mechanism for the control of oxygen diffusion through the nodules. 相似文献
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The role of temperature in determining the stimulation of CO2 assimilation at elevated carbon dioxide concentration in soybean seedlings 总被引:1,自引:0,他引:1
Soybean ( Glycine max cv. Clark) was grown at both ambient (ca 350 μmol mol−1 ) and elevated (ca 700 μmol mol−1 ) CO2 concentration at 5 growth temperatures (constant day/night temperatures of 20, 25, 30, 35 and 40°C) for 17–22 days after sowing to determine the interaction between temperature and CO2 concentration on photosynthesis (measured as A, the rate of CO2 assimilation per unit leaf area) at both the single leaf and whole plant level. Single leaves of soybean demonstrated increasingly greater stimulation of A at elevated CO2 as temperature increased from 25 to 35°C (i.e. optimal growth rates). At 40°C, primary leaves failed to develop and plants eventually died. In contrast, for both whole plant A and total biomass production, increasing temperature resulted in less stimulation by elevated CO2 concentration. For whole plants, increased CO2 stimulated leaf area more as growth temperature increased. Differences between the response of A to elevated CO2 for single leaves and whole plants may be related to increased self-shading experienced by whole plants at elevated CO2 as temperature increased. Results from the present study suggest that self-shading could limit the response of CO2 assimilation rate and the growth response of soybean plants if temperature and CO2 increase concurrently, and illustrate that light may be an important consideration in predicting the relative stimulation of photosynthesis by elevated CO2 at the whole plant level. 相似文献