. Manual of fruit diseases . Fruit. 392 MANUAL OF FRUIT DISEASES and related plants like the juneberry, hawthorn and apple. But in order to complete the life-historj^ it must have the red cedar, or juniper {Juniperus communis and J. virginiana). On the red cedar twigs there are produced peculiar canker-like lesions (Fig. 116). These diseased- spots begin their development in midsummer. The fungus hibernates within the twig as mycelium. With the advent of the first warm, moist spring weather the fungus resumes growth and development. On the surface of the affected area numerous yellow, gelatino
. Manual of fruit diseases . Fruit. 392 MANUAL OF FRUIT DISEASES and related plants like the juneberry, hawthorn and apple. But in order to complete the life-historj^ it must have the red cedar, or juniper {Juniperus communis and J. virginiana). On the red cedar twigs there are produced peculiar canker-like lesions (Fig. 116). These diseased- spots begin their development in midsummer. The fungus hibernates within the twig as mycelium. With the advent of the first warm, moist spring weather the fungus resumes growth and development. On the surface of the affected area numerous yellow, gelatinous masses appear,— the teliospores of the fungus. Each teliospore germinates by develop- ing a short tube (promycelium) on which four sporidia are borne. These sporidia are discharged in thousands, carried by the wind, and some of them infect the quince or the related plants already listed. The sporidia never reinfect the cedars. On the quince, the sporidia germinate, form- ing germtubes which grow into the tissues of the fruit and twig, causing the distortions and malformations already described. Finally the tubu- lar projections, which in mass are an orange fringe-like growth, develop another sort of spores, — aecio-spores. These are peculiar, like the sporidia developed on the cedar, in that they cannot reinfect the quince, but may infect the cedars. About one year is re- quired for the completion of the life-history of this Fig. 116. — Quince-rust on red 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 Hesler, L. R. (Lexemuel Ray); Whetzel, Herbert Hice, 1877-1944. New York : Macmillan
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Keywords: ., bookcentury1900, bookdecade1910, bookpublishernewyo, bookyear1917
