Search
Close
Search
Advanced Search
Search Menu
AI Discovery Assistant

Abstract

A comparative study was made on the effects of indol-3yl-acetic acid (IAA), maleic hydrazide (MH), naphthalene acetic acid (NAA), and gibberellic acid (GA) at a concentration of 1o-1 mg I-1, on the growth and metabolism of Oryza sativa L., cv. Bhasamanik. All the growth substances excepting NAA caused promotion of root elongation and increased the number of roots formed but had very little effect on shoot growth. NAA was found to have a retarding effect on the general growth of the plant, but also increased the number of roots formed.

At the concentration used IAA caused enhanced protein synthesis in parallel with increased root growth. However, with MH no such direct relationship could be observed between root growth and protein synthesis at the early stage, but stimulation of root growth was directly related to increased protein synthesis at the later stage. Despite the adverse effect of NAA on the growth of the plant, protein synthesis was not affected. In fact a general increase in the protein content of the plant was observed. In plants treated with GA increased sugar content and enhanced protein synthesis were noted.

The levels of free amino acids were found to be affected markedly by the application of the growth regulators. With NAA treatment an accumulation of asparagine in the shoot and with GA an increase in the level of alanine in the root were noted. Aspartic acid decreased in the roots, but increased in the shoots of treated plants. Glutamic acid was lower in plants treated with IAA, MH, and NAA, while treatment with GA increased it in the shoot at the tillering stage. In the shoots of IAA-, MH-, and NAA-treated plants an increase in the quantity of serine was noted whereas under the action of GA both serine and glycine decreased.

This content is only available as a PDF.
© Oxford University Press
Issue Section:
Articles
You do not currently have access to this article.
Download all slides