Seedings
Mostrando 13-21 de 21 artigos, teses e dissertações.
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13. Asparagine Synthetase in Corn Roots 1
The level of asparagine synthetase is low in 10-mm root tips from corn seedings (Zea mays W64 × W182F) but relatively high in mature root sections taken 20 to 35 mm from the tip. When root tips are excised there is a marked increase in asparagine synthetase over a 5-hour period. In mature root sections, on the other hand, the asparagine synthetase activity
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14. Uptake and Growth-promoting Activity of Indoleacetic Acid in Segments of Cold-hardened Wheat Coleoptiles 1
Seedings of winter wheat (Triticum aestivum L. cv. Kharkov MC 22) were grown at 24 C (unhardened) and 4 C (hardened). Indoleacetic acid (IAA) was added to excised coleoptile segments after lengthy incubation and their responses were determined by photometric auxanometry at both 25 C and 5 C. The segments' rates of uptake of 14CIAA were also compared at both
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15. Regulation of Photosynthetic Activity in the Primary Leaves of Bean (Phaseolus vulgaris L.) by Materials Moving in the Water-conducting System
Endogenous factors which determine the photosynthetic capacity of the leaf were studied in the fully expanded, primary leaves of young seedings of bean (cv. Bulgarian). Following removal of the shoot above the primary leaf node and excision of all axillary buds, the primary leaves increased in area and thickness, in chlorophyll content, in levels of soluble
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16. Distribution and Development of Nitrate Reductase Activity in Germinating Cotton Seedlings 1
Activity of nitrate reductase in roots and cotyledons of cotton seedings (Gossypium hirsutum L. cv. Deltapine 16) increased rapidly on germination, reaching a maximum after 1 day of imbibition. Thereafter, activity declined until emergence and greening of the cotyledons, when it again began to increase steadily. Germinating soybean (Glycine max (L.) Merrill
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17. A metal-accumulator mutant of Arabidopsis thaliana.
A mutation designated man1 (for manganese accumulator) was found to cause Arabidopsis thaliana seedlings to accumulate a range of metals. The man1 mutation segregated as a single recessive locus located on chromosome 3. When grown on soil, mutant seedlings accumulated Mn (7.5 times greater than wild type), Cu (4.6 times greater than wild type), Zn (2.8 times
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18. Influence of Environmental Factors on Interstrain Competition in Rhizobium japonicum†
The effect of several biotic and abiotic factors on the pattern of competition between two strains of Rhizobium japonicum was examined. In two Minnesota soils, Waseca and Waukegan, strain USDA 123 occupied 69% (Waseca) and 24% (Waukegan) of the root nodules on Glycine max L. Merrill cv. Chippewa. USDA 110 occupied 2% of the root nodules in the Waseca soil an
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19. Post-Transcriptional Regulation of Catalase Isozyme Expression in Cotton Seeds.
We reported previously that expression of the five tetrameric catalase isozymes during postgerminative growth of cotton seedings was a consequence of interactions between two subunits (SU 1 and SU 2) temporally synthesized from two distinct catalase genes. In this study, we focused on the regulation of the expression of these two catalase subunits during the
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20. Auxin Transport as Related to Leaf Abscission during Water Stress in Cotton 1
Plant water deficits reduced the basipetal transport of auxin in cotyledonary petiole sections taken from cotton (Gossypium hirsutum L.) seedings. A pulse-labeling technique was employed to eliminate complications of uptake or exit of 14C-indoleacetic acid from the tissue. The transport capacity or the relative amount of radioactivity in a 30-minute pulse wh
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21. Physical association of KAB1 with plant K+ channel alpha subunits.
K+ channel proteins contain four alpha subunits that align along a central axis perpendicular to membranes and form an ion-conducting pore. Recent work with K+ channels native to animal membranes has shown that at least some members of this protein family also have four beta subunits. These structural components of the holoenzyme each form tight associations