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1.
Jerry W. McClure 《Phytochemistry》1974,13(7):1065-1069
Five-day-old etiolated barley shoots respond to brief illumination with red light by increasing their level of PAL ca 50% within 5 hr. When assayed s 相似文献
2.
《Bioscience, biotechnology, and biochemistry》2013,77(12):2762-2765
Comparative two-dimensional electrophoresis showed six proteins, which were significantly produced in the root of salt-tolerant barley. These proteins were identified as stress/defense-related proteins that do not scavenge reactive oxygen species directly, suggesting that salt-tolerant barley develops not only an antioxidative system, but also physical and biochemical changes to cope with salt stress. 相似文献
3.
4.
5.
Emergence and growth of barley was severely decreased by short periods (less than 24 hours) of pre-emergence waterlogging
at 20°C. The extent of damage depended on a combination of duration of waterlogging, soil water potential and aggregate size.
Potentials of less than—4kPa prevented loss of plants developing in aggregates of less than 2 mm diameter after a transitory
period of waterlogging although some shoot and root damage occurred. By comparison seeds growing in soil consisting of aggregates
greater than 2 mm in diameter were not damaged by transitory waterlogging even when drainage only occurred at−0.8kPa. The
severity of damage increased with the period of waterlogging. A criterion obtained as the product of mean size grade and water
potential gave a single value (−4NM−1) below which emergence was satisfactory. Waterlogging halfway through germination gave more severe damage than near sowing
date or near emergence. 相似文献
6.
For three acid soils from Santa Catarina, Brazil, lime application and time of incubation with lime had little effect on the
adsorption of added phosphorus. In two soils with high contents of exchangeable aluminium, solution P and isotopically exchangeable
P were decreased by incubating with lime for 1 month: phosphorus was probably adsorbing on freshly precipitated aluminium
hydrous oxides. In one soil with less exchangeable aluminium, P in solution was increased by liming. After 23 months lime
increased solution and exchangeable P possibly due to crystallization of aluminium hydrous oxides reducing the number of sites
for P adsorption. All these changes were however small.
In a pot experiment, lime and phosphorus markedly increased barley shoot and root dry matter and P uptake. Although liming
reduced P availability measured by solution P, isotopically exchangeable P and resin extractable P, it increased phosphorus
uptake by reducing aluminium toxicity and promoting better root growth. The soil aluminium saturation was reduced by liming,
but the concentration of aluminium in roots changed only slightly. The roots accumulated aluminium without apparently being
damaged. 相似文献
7.
Anin situ method, derived from anin vivo method, was used to determine nitrate reductase activity (NRA) in:i) excised barley and corn shoots and excised soybean leaves
during a N-depletion experiment and; ii) roots and shoots of N-depleted barley and corn seedlings during induction of nitrate,
reductase (NR). Nitrate reduction, calculated from thesein situ RNA measurements, was compared with estimates of each organ's nitrate reduction in light aerobic conditions from NO
3
−
consumption and a15N model (Gojonet al., 1986b).
Thein situ RNA of roots strongly underestimated their15NO
3
−
reduction. In contrast, in barley and corn shoots and in the first trifoliolate leaves from 26-day-old, soybean, thein situ NRA assay gave a fair approximation of the true NO
3
−
reduction rate (relative differences ranging from −14 to +32%). In young soybean leaves (from 20-day-old plants), however,
thein situ NRA strongly underestimated the actual NO
3
−
reduction. The physiological significance of thein situ NRA assay in shoots and roots, and its value for field studies are discussed from these results. 相似文献
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10.
Ross O. Nable 《Plant and Soil》1988,112(1):45-52
The mechanism of resistance toB toxicity in barley and wheat was studied in a solution culture experiment using several cultivars displaying a large range of sensitivity to excessB supply. Plants were cultured for 35 d atB concentrations ranging from normal to excessive (15 to 5000 M, respectively) then examined for dry matter production and theB distribution between roots and shoots.In both species, increasedB supply was accompanied by increased tissueB concentrations, development ofB toxicity symptoms and depressed growth. At each level ofB supply, however, resistant cultivars accumulated considerably lessB than did sensitive cultivars, in both roots and shoots. Even at the lowestB supply, at which noB toxicity symptoms developed and growth was not affected, resistant cultivars maintained relatively low tissueB concentrations. No cultivar displayed an ability to tolerate high tissueB concentrations.These results indicate that sensitivity toB toxicity in barley and wheat is governed by the ability of cultivars to excludeB. If theB concentrations of tissues is used to indicate resistance toB toxicity, then cultivars have the same ranking whether cultured at a normal or excessB supply. 相似文献