Fungi, Ascomycetes, Ustilaginales, Uredinales . -spore of T. Tritici the nucleus passesinto the basidium and divides three times so that eight nuclei are basidiospores are budded off in abunch at the apex of the basidium, andeach receives a single nucleus. Frequentlyadditional nuclear divisions take placeand ten, twelve, or sixteen uninucleatespores may be produced. When the sporesare fully formed short conjugating tubesgrow out and connect neighbouringspi nes, often while these are still attachedto the basidium (fig. 161). According to Rawitschcr the nucleusof one cell of the pai
Fungi, Ascomycetes, Ustilaginales, Uredinales . -spore of T. Tritici the nucleus passesinto the basidium and divides three times so that eight nuclei are basidiospores are budded off in abunch at the apex of the basidium, andeach receives a single nucleus. Frequentlyadditional nuclear divisions take placeand ten, twelve, or sixteen uninucleatespores may be produced. When the sporesare fully formed short conjugating tubesgrow out and connect neighbouringspi nes, often while these are still attachedto the basidium (fig. 161). According to Rawitschcr the nucleusof one cell of the pair passes over intothe other and the nuclei lie near oneanother but without fusion. After con-jugation the spores may become septate;from those which contain two nuclei fila-ments of binucleate cells grow out, andmay give rise to conidia which are also binucleate. Under suitable conditionsthe binucleate hyphae bring about infection by pushing between the cellsof the host seedling. In the cells of the sporogenous mycelium fusion of the 1 3. Fig 161. Tilletia Tritici (Bjerk) Wint.;a. basidium ihirly hours after germination1 if brand-spore; /. conjugation of basidio-spores : ? .,oo: after Plowright. 194 HEMIBASIDIOMYCETES [ch. pairs of associated nuclei takes place. Rawitscher observed a quite similarlife-history in T. lacvis. In the parasitic mycelium of Doassansia Alismatis and Entyloma Glaucii(fig. 162) Dangeard observed binucleate cells and the fusion of their nuclei
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectfungi, bookyear1922
