PUCCINIACEAE के जीनस टाइप करें; परजीवी कवक का एक बड़ा जीनी जिसमें कई लोग विभिन्न आर्थिक संयंत्रों के लिए विनाशकारी हैं

puccinia's Usage Examples:

(3) A most important difference is observable in the liability to attacks of rust (Puccinia), some varieties being almost invariably free from it, while others are in particular localities so subject to it as to be not worth cultivating.

Just as the uredospores and aecidiospores both show these specialized characters in the case of Puccinia graminis so we find that both the conidia and ascospores of E.

A similar specialization has been observed by Marshall Ward in the Puccinia parasitic on species of Bromus, and by Neger, Marchal and especially Salmon in the Erysiphaceae.

Eriksson found, for example, that the well-known species Puccinia graminis could be split up into a number of forms which though morphologically similar were physiologically distinct.

- Puccinia graminis.

Among the simplest cases are the sheet-like aggregates of sporogenous hyphae in Puccinia, Uromyces, 'c., or of basidia in Exobasidium, Corticium, 'c., or of asci in Exoascus, Ascocorticium, 'c. In the former, where the layer is small, it is often termed a sorus, but where, as in the latter, the sporogenous layer is extensive, and spread out more or less sheet-like on the supporting tissues, it is more frequently termed a hymenium.

As regards their geographical distribution, fungi, like flowering plants, have no doubt their centres of origin and of dispersal; but we must not forget that every exchange of wood, wheat, fruits, plants, animals, or other commodities involves transmission of fungi from one country to another; while the migrations of birds and other animals, currents of air and water, and so forth, are particularly efficacious in transmitting these minute organisms. Against this, of course, it may be argued that parasitic forms can only go where their hosts grow, as is proved to be the case by records concerning the introduction of Puccinia malvacearum, Peronospora viticola, Hemileia vastatrix, 'c. Some fungi - e.g.

those due to .Synchytrium, Protomyces, Cysto pus, many Ustilagineae, 'c. These cases are not easily distinguished superficially froni the pustular outgrowth of actual mycelia and spores (stromata) of such Fungi as Nectria, Puccinia, 'c. The cylindrical stem-swellings due to Calyptospora, Epichloe, 'c., may also be mentioned here, and the tyro may easily confound with these the layers and cushions of eggs laid on similar organs by moths.

Similarly with Anemone infested with Puccinia and Vacciniusn with Catyptospora, and many other cases of deformations due to hypertrophy or atrophy.

Schinzia, which forms galllike swellings on the roots of rushes; Gymnosporangium, causing excrescences on juniper stems; numerous leaf Fungi such as Puccinia, Aecidium, Sep/one, 'c., causing yellow, brown or black spots on leaves; or Ustilago in the anthers of certain flowers.

puccinia's Meaning':

type genus of the Pucciniaceae; a large genus of parasitic fungi including many that are destructive to various economic plants