. The botany of crop plants; a text and reference book. Botany, Economic. 372 BOTANY OF CROP PLANTS Pollination and Fertilization.^—The literature on this subject is extensive. Cross-poUination is the rule and self-pollination the exception in the apple and pear. Ex- periments have shown that the wind aids but little in cross- pollination, and that insects, chiefly the honey bee, are relatively more important. The bee is attracted to the flowers by the nectar which is produced rather Fig. 156.—Floral diagram of apple (Malus sylvestris). Note that the sta- mens are in three distinc
. The botany of crop plants; a text and reference book. Botany, Economic. 372 BOTANY OF CROP PLANTS Pollination and Fertilization.^—The literature on this subject is extensive. Cross-poUination is the rule and self-pollination the exception in the apple and pear. Ex- periments have shown that the wind aids but little in cross- pollination, and that insects, chiefly the honey bee, are relatively more important. The bee is attracted to the flowers by the nectar which is produced rather Fig. 156.—Floral diagram of apple (Malus sylvestris). Note that the sta- mens are in three distinct whorls. (After Kraus.) Self-sterility and Self-fertility.—Many apples and pears are self-sterile, that is, will not fertilize their own pistils. In .such cases, pollen from another variety will usually result in fertilization. Self-sterility and self-fertility probably vary with different climatic conditions. In Oregon, Lewis and Vincent found that the Spitzenburg is self-sterile but capable of being fertilized with pollen from a number of other varieties, such as Yellow Newton, Arkansas Black, Jonathan, and Baldwin. Evidently, the mutual affinities of apple varieties must be considered in setting out an orchard. It would not be well to plant solid blocks of Spitzenburg, for example. It should be alternated with rows of some one of. 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 Robbins, Wilfred William, 1884-1952. Philadelphia, P. Blakiston's Son & Co
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Keywords: ., booka, bookcentury1900, bookdecade1910, booksubjectbotanyeconomic
