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RELATION OF LOOSE SMUT TO YIELD OF BARLEY |
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Canadian Journal of Research,
Volume 20c,
Issue 10,
1942,
Page 491-500
Wm. Semeniuk,
J. G. Ross,
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摘要:
A simple technique was devised to inoculate barley withUstilago nuda(Jens.) K. and S. in order to facilitate the study of the effect of loose smut on yield. Infected seed lots so obtained were mixed in different proportions with normal seed to provide at least six levels of infection ranging from nearly zero to the maximum. The infection levels were planted in replicated field test plots at three stations in each of two years.No significant correlations were obtained between yield of barley and the percentage loose smut in the 1939 trials. A direct linear relationship was obtained in 1940 between percentage incidence of loose smut and the reduction in yield. For every 1% increase in loose smut, yield was reduced 0.85% at St. Paul, Minn., 1.4% at Edmonton, and 1.2% at Fallis, Alta. These regression coefficients are not significantly different. Loose smut did not affect tillering noticeably. Similar infections of loose smut were obtained at all stations for comparable seed lots. Higher infections were observed as the rate of seeding was increased. The incidence of loose smut at Edmonton was the same on the basis of percentage smutted spikes as on the basis of percentage smutted plants.
ISSN:1923-4287
DOI:10.1139/cjr42c-041
出版商:NRC Research Press
年代:1942
数据来源: NRC
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HOST-PARASITE RELATIONSHIPS IN A SEED-BORNE DISEASE OF BARLEY CAUSED BYHELMINTHOSPORIUM SATIVUMPAMMEL, KING, AND BAKKE |
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Canadian Journal of Research,
Volume 20c,
Issue 10,
1942,
Page 501-523
H. W. Mead,
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PDF (1798KB)
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摘要:
A hulled barley kernel is a caryopsis enclosed by the tightly adhering floral glumes. The testa, which is formed from the inner integument of the ovule, becomes increasingly resistant to fungi. Spikelets may become parasitized during flowering and afterwards, by air-borne spores and fragments of mycelium ofH.sativum. The fungus may cause blighting, shrivelling, and discoloration of the spikelets and maturing kernels, the damage depending upon the time of inoculation. Irregular, dark, thick-walled mycelium may be found massed in the parenchyma of the glumes, pericarp, and lodicules, and ungerminated spores between the glumes and pericarp. This dormant mycelium will remain viable for from two to five years. It germinates when the kernel germinates and infects the young tissues of the plumule and radicle as these organs expand and force their way through and past the infected tissues. It also colonizes the soil nearby, to a limited extent. Embryo blight, pre-emergence and postemergence blight, with malformation, stunting, and lesioning of the seedling may follow infection, the amount of each depending upon certain environmental factors.
ISSN:1923-4287
DOI:10.1139/cjr42c-042
出版商:NRC Research Press
年代:1942
数据来源: NRC
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