Titlebook: Seed Pathology; Volumes 1 and 2 Paul Neergaard Textbook 1977Latest edition Macmillan Publishers Limited 1977 pathology.seed.Volume

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Macmillan Publishers Limited 1977

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Diseases and Injuries of SeedThe fact that seeds are both vehicles and victims of disease calls for some clarification of concepts. So do the facts that seeds, without being diseased, may be vehicles of pathogens, as well as they may be victims of detriments other than disease, such as insect damage.

特征

Seed-borne VirusesAlthough most viruses are not seed-borne the number of viruses for which seed transmission has been recognised is steadily growing, and in some genera within the phanerogams seed transmission is rather frequent. This holds true for certain genera of leguminous plants (Leguminosae), stone fruits (Amygdalaceae) and composites (Compositae).

禁止

Seed-borne BacteriaBacteria are commonly carried on seed; potentially, any bacterial plant pathogen may probably be seed-transmitted.

Density

Types of Host in Relation to Types of PathogenThere are considerable differences between seeds of different kinds in regard to frequency of transmission of any one pathogen, and in the number of different pathogens so transmitted. Seed-borne pathogens and transmission are common in cereals and legumes but relatively infrequent in forestry seed and many flower seeds.

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Fantasy

Environmental Physicochemical Factors Affecting Establishment and Course of DiseaseA discussion of the conditions leading to inception and establishment of diseases through transmitted seed falls naturally into the following two items:

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捏造

Seed-borne Fungiome are easily detected, others do occur but cannot be revealed by conventional testing procedures. The extent to which fungi occur in seeds depends on their capability to survive under the extreme dry conditions of seed as a carrier.

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