About Us | Help Videos | Contact Us | Subscriptions



This article in AJ

  1. Vol. 68 No. 4, p. 617-621
    Received: July 3, 1975

Request Permissions


Nitrogen Concentrations of Cotton Leaves, Buds, and Bolls in Relation to Age and Nitrogen Fertilization1

  1. A. C. Thompson,
  2. H. C. Lane,
  3. J. W. Jones and
  4. J. D. Hesketh2



Our plant growth models depend on a nitrogen economy in the plant as a limit for the initiation of new organs as well as the slowing of growth or abscission of plant organs. To improve our N-balance model, we needed better information about possible organ age effects for plants growing under different N-levels.

Leaf and fruit N and N-effects upon morphology at four preplanting soil nitrogen levels of 0, 67, 134, and 201 kg N/ha were studied in cotton (Gossypium hirsutum) in the field and greenhouse. Three sets of leaves and fruit were monitored for N-content throughout the season. N-concentration in leaves from each N-treatment decreased (6 to 2%) as the season progressed. Regression analysis of these data indicated that the N-concentration dilution was not linear with time. Seventy-nine percent of the variation in N-concentratlon could be accounted for by N-application rate and time in growing season. Regression analysis of fruit data indicated that the dilution of N-concentration (4.5 to 1.5%) was linear with N-application rate. However N-concentration dilution was significant for young fruit from older plants. In plants grown both in the field and greenhouse at the four N-levels, the flowering rule time values (days/flower) increased with lower N-rates. There was a delay in maturity of floral buds in the high N-treatment plants, but no delay in the time required for boll set.

  Please view the pdf by using the Full Text (PDF) link under 'View' to the left.

Copyright © .