. Annals of applied biology. Biology, Economic; Biochemistry. S. p. Wiltshire 189 spring, fissures arise which expose the tissues of the leaf base and readily allow the canker fungus to enter. The host only slowly reacts against the fungus which therefore quickly develops, in many cases surrounding the stem and killing off the shoot above it. The view that the cracks resulting from the growth of the buds, afford a means of entrance to the fungus in the spring, is also strengthened by the observation, given above mth regard to the times of appearance of bud infection. The Medaille d'Or x Kingst
. Annals of applied biology. Biology, Economic; Biochemistry. S. p. Wiltshire 189 spring, fissures arise which expose the tissues of the leaf base and readily allow the canker fungus to enter. The host only slowly reacts against the fungus which therefore quickly develops, in many cases surrounding the stem and killing off the shoot above it. The view that the cracks resulting from the growth of the buds, afford a means of entrance to the fungus in the spring, is also strengthened by the observation, given above mth regard to the times of appearance of bud infection. The Medaille d'Or x Kingston Black seedhngs are. Text-fig. 2. Radial longitudinal section showing infection of the leaf base and the crack through which the fungus first entered. There is no sign of phellogen formation and the mycelium has penetrated deeply in the intercellular spaces. An infection of Venturia inaequalis can be seen on the outside of the stem, x 25. m = mycelium; =leaf trace; fe = limit of infected region; 2'=pycnidia; a= Venturia inaequalis. naturally exceptionally late in bursting into leaf, but until this takes place only very occasional infections can be found on the previous season's growth. It appears that there is a definite correlation between the appearance of canker and the swelling of the buds on the Kingston Black X Medaille d'Or seedhngs and this fact points to the conclusion that the growth cracks which accompany bud development allow the entrance of the fungus. A point of interest which may be mentioned here is that further infections of the canker fungus on the Kingston Black x Medaille d'Or. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Association of Applied Biologists; Association of Economic Biologists. [Wellesbourne, Warwick, etc. ] Association of Applied Biologists [etc. ]
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectbiochem, bookyear1921
