Bulletin Volume 86

Bulletin Volume 86

List price: US$15.31

Currently unavailable

Add to wishlist

AbeBooks may have this title (opens in new window).

Try AbeBooks


This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1912 edition. Excerpt: ...Allantoin appears therefore to be a body which has an effect on plant growth, when no nitrate is present, but as soon as even the smallest amount of nitrate is available to the plant, the allantoin has no further effect on growth. We would conclude from this that allantoin is of only indifferent value as a direct nutrient for wheat. CYSTEIN. Cystein and cystin are closely related compounds. Cystin is a constant and abundant dissociation product of most albumins. Although often accompanied by cystein, the cystin is held to be the primary dissociation product of the albumin. Cystein is formed from cystin by reduction, which can be accomplished in the laboratory with granulated tin and hydrochloric acid. The crystalline cystein so prepared was used in these experiments. Owing to the fact that cystein in aqueous solution is oxidized to cystin on exposure to air, the result of the tests may not be wholly due to cystein alone, as it is probable that a portion at least went over into cystin. Of the effect of the latter by itself we have no evidence other than that from an earlier preliminary experiment, in which the cystin appeared to be so insoluble in the culture solutions that no noticeable effect on growth was produced. It would, therefore, appear that neither cystin nor cystein had any decided effect on plant growth, as is shown in the following. The effect of cystein on plants was tried by adding 50 parts per million to each solution, the total number of 66 cultures being used in the test, a control set being grown at the same time. The solutions were changed every three days, but no analyses were made. The wheat seedlings grew from January 17 to January 29, 1912. No perceptible difference in the appearance of the two sets of cultures was...show more

Product details

  • Paperback | 50 pages
  • 189 x 246 x 3mm | 109g
  • Rarebooksclub.com
  • United States
  • English
  • black & white illustrations
  • 1236864166
  • 9781236864161