. Elementary plant physiology. Plant physiology. Elementary Plant Physiology. 133. Movements in response to a combination of geotropism and phototropism—Force into bloom a number of bulbs of Narcissus, which may be obtained from dealers. Set one upright on a table, and cover with a card- board box with an opening in one side, at the level of the opening flowers. Note the position taken by the flowers. The pedicels will be found to move to a horizontal position, with the axis of the flower directed toward the source of light. Take a second plant, in which the flowers have already assumed the ho
. Elementary plant physiology. Plant physiology. Elementary Plant Physiology. 133. Movements in response to a combination of geotropism and phototropism—Force into bloom a number of bulbs of Narcissus, which may be obtained from dealers. Set one upright on a table, and cover with a card- board box with an opening in one side, at the level of the opening flowers. Note the position taken by the flowers. The pedicels will be found to move to a horizontal position, with the axis of the flower directed toward the source of light. Take a second plant, in which the flowers have already assumed the hori- zontal position, and lay the plant inclined or hori- zontally, fastening the scapes in such manner that the pedicels lie in various planes. Note the exact positions of half a dozen flowers. Examine a day later, and describe the movements entailed. 134. Hydrotropism of roots Secure a small wooden box which will hold sufficient moist sawdust to ger- minate seedlings of peas or beans. Take away the top and bottom, and replace with wire or cloth gauze. Fill the box with sawdust thoroughly saturated in water, and imbed seed- lings in the sawdust. Attach cords to the box in such man- ner that it may be suspended from a support, or provide means of tilting it at an angle of 45 degrees. The box must be so shallow that the roots in the natural course of growth. Fig. 94.—Box with perforated bottom, filled with sawdust, to demonstrate hydro- tropic reaction of roots. After 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 MacDougal, Daniel Trembly, 1865-1958. New York, London [etc. ] Longmans, Green, and Co.
Size: 1309px × 1908px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, booksubjectplantph, bookyear1902
