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TETRAPLOIDTARAXACUM KOK-SAGHYZ: III. ACHENE WEIGHT, FLOWERING, AND PLANT DEVELOPMENT |
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Canadian Journal of Research,
Volume 25c,
Issue 2,
1947,
Page 59-72
M. W. Bannan,
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摘要:
The ultimate size of diploid or tetraploid kok-saghyz plants, when grown in pots or at wide spacings in the field, was not determined primarily by the weight of the achenes from which they originated. Conversely large or small tetraploids when crossed among themselves did not produce achenes reflecting the differences in plant size. Tetraploids differed from diploids in possessing larger organs, but increase in size was more or less counteracted by reduction in numbers. This was especially true as regards flowering. Tetraploids were notably deficient in the production of inflorescences during the first year, and since they were correspondingly freed from the inhibiting effects of flower and seed development on root enlargement, the root size of the vegetating tetraploids tended to surpass that of the more floriferous diploids, unless the latter were disbudded. On the whole first-year plants with the broadest and leafiest rosettes and few or no capitula developed the biggest roots. An association of such characteristics is probably the best criterion for the selection of large-rooted plants. When large root size is desired it would seem advisable to avoid pregermination treatments that hasten maturation and stimulate flowering.
ISSN:1923-4287
DOI:10.1139/cjr47c-007
出版商:NRC Research Press
年代:1947
数据来源: NRC
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ERYSIPHE GRAMINISIN CANADA |
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Canadian Journal of Research,
Volume 25c,
Issue 2,
1947,
Page 73-94
Margaret Newton,
W. J. Cherewick,
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PDF (1109KB)
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摘要:
A study has been made of powdery mildew (Erysiphe graminisDC.) in Canada, including its distribution, the physiologic specialization of its two varieties,HordeiandTritici, and the reactions of barley and wheat hosts to the prevalent races of the two varieties of mildew. The fungus occurs throughout Canada but it is most prevalent in British Columbia, Ontario, and Quebec. Nine races ofE.graminis Hordeiand three ofE.graminis Triticihave been identified. Races 3, 6, 8, and 9 of the former, and races 4 and 5 of the latter are the most common in Canada. At a higher temperature (25 °C.) practically all the races of mildew developed a more resistant type of infection than at a lower temperature (15 °C.). The only exception was race 6 ofE.graminis Hordei, which thrived fairly well at the higher temperature.The reactions of 246 varieties and strains of barley to nine races of barley mildew and the reactions of 124 wheat varieties and strains to two races of wheat mildew indicate that there are varieties of both cereals that are resistant to powdery mildew.
ISSN:1923-4287
DOI:10.1139/cjr47c-008
出版商:NRC Research Press
年代:1947
数据来源: NRC
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