摘要:

Sparling, ShirleyR. (U. California, Santa Barbara, Goleta.)A report on the culture of some species of Halosaccion, Rhodymenia, and Fauchea.Amer. Jour. Bot. 48(6): 493–499. Illus. 1961.—Cultures of the red algae,Halosaccion glandiforme(Gmelin) Ruprecht,Rhodymenia palmataf.mollisSetchell et Gardner,Fauchea laciniataJ. G. Agardh, andF. fryeanaSetchell were started from spores and in some instances maintained for about 2½ yr. Culture methods are described and the plants obtained in culture compared to those in nature. Of the plants cultured, only some ofF. laciniatabecame fertile. The use of spores undergoing their first division in germination for observation of mitotic divisions is reported.

ISSN:0002-9122    

DOI:10.1002/j.1537-2197.1961.tb11674.x

出版商:Wiley    

年代:1961

数据来源: WILEY

摘要:

Bianchi, D. E. (San Fernando Valley State Coll., Northridge, Calif.)A small‐colony variant of Candida albicans.Amer. Jour. Bot. 48(6): 499–503. Illus. 1961.—Normal cultures ofCandida albicansgive rise to a small‐colony variant similar in many respects to the “petite” ofSaccharomyces cerevisiae.The difference in colony size is due to a difference in the rate of cell division. They arise spontaneously from the wild‐type at a frequency of from 1–3%, and the individual cells of both types are the same size. However, unlike the “petite,” they contain the enzymes cytochrome oxidase, cytochromeb, and succinic dehydrogenase, and they respire normally.

ISSN:0002-9122    

DOI:10.1002/j.1537-2197.1961.tb11675.x

出版商:Wiley    

年代:1961

数据来源: WILEY

摘要:

Bertsch, WalterF., and WilliamS. Hillman. (Yale U., New Haven, Conn.)The photoinhibition of growth in etiolated stem segments. I. Growth caused by sugars in Pisum.Amer. Jour. Bot. 48(6): 504–511. Illus. 1961.—Etiolated pea stem segments were used to study the red, far‐red reversible photoinhibition of stem growth. The growth of immature, apical tissue was insensitive to light after excision from the seedling, unless a growth‐promoting sugar (sucrose, glucose, fructose) was included in the medium. Red light specifically inhibited the growth caused by the sugars. Growth promotions of the same magnitude caused by indoleacetic acid or gibberellic acid were not reduced by irradiation of the tissue. The effects of various other sugars were tested. Arabinose and galactose, which do not promote growth, did not cause photosensitive growth in the isolated tissue. Mannose and xylose promoted growth at low concentrations, and this small promotion was inhibited by irradiation. Phptoinhibition occurred even at inhibitory concentrations of mannose and xylose. The distinctness of light‐sensitive growth is discussed, and the photoinhibition of a growth process which is limited by availability of sugars is suggested.

ISSN:0002-9122    

DOI:10.1002/j.1537-2197.1961.tb11676.x

出版商:Wiley    

年代:1961

数据来源: WILEY

摘要:

Barr, Rita, and M. L. Tomes. (Purdue U., Lafayette, Indiana.)Variation in the tomato‐leafmold organism, Cladosporium fulvum.Amer. Jour. Bot. 48(6): 512–515. Illus. 1961.—Seven biochemical mutants ofCladosporium fulvumCke. were obtained by irradiating spores with ultraviolet light. Various combinations of 2 mutants failed to grow on minimal medium when the mixtures were made by shaking spore suspensions in deionized water. When the various combinations of 2 mutants were grown together on complete medium for one generation prior to transfer to minimal medium, 2 combinations were successsful. The same 2 mutant pairs grew directly on minimal medium when spores and mycelium were mixed, centrifuged, and plated as pellets. These results suggest that heterocaryosis may occur in the tomato‐leaf‐mold organism. Diffusion tests performed with pairs of biochemical mutants showed that no cross‐feeding between mutants occurred through the agar. Both parental types were reisolated from the presumed heterocaryon, 2 plus 6. The presence of anastomoses and occasional binucleate spores and mycelial cells was observed.

ISSN:0002-9122    

DOI:10.1002/j.1537-2197.1961.tb11677.x

出版商:Wiley    

年代:1961

数据来源: WILEY

摘要:

Lockhart, JamesA. (U. Hawaii, Honolulu.)Interactions between gibberellin and various environmental factors on stem growth.Amer. Jour. Bot. 48(6): 516–525. Illus. 1961.—The interactions between gibberellin and various environmental factors on stem elongation of greenhouse‐grownPhaseolus vulgarishave been studied in steady‐state growth systems. The action of gibberellin was found to be independent of rate of accumulation of photosynthetic products, root activity, temperature, water availability and both ultraviolet and X‐radiation. It was also shown that gibberellin interacts completely with red/far‐red radiation given at the end of the daily light period. This interaction is complete even when maximum growth rates are experimentally reduced by limiting various independent factors. These results are interpreted as demonstrating that red/far‐red radiation controls rate of stem elongation in greenhouse‐grown plants through an effect on the endogenous gibberellin system of the plant. None of the other environmental factors studied seems to act through the gibberellin system.

ISSN:0002-9122    

DOI:10.1002/j.1537-2197.1961.tb11678.x

出版商:Wiley    

年代:1961

数据来源: WILEY

ISSN:0002-9122    

DOI:10.1002/j.1537-2197.1961.tb11679.x

出版商:Wiley    

年代:1961

数据来源: WILEY