HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Moore, P. A. Articles by Patrick, W. H. Search for Related Content PubMed Articles by Moore, P. A., Jr. Articles by Patrick, W. H., Jr. Agricola Articles by Moore, P. A. Articles by Patrick, W. H.

Factors Affecting Rice Growth on Acid Sulfate Soils

Univ. of Arkansas, P.O. Box 3508, Monticello, AR 71655

T. Attanandana

Soil Science Dep., Kasetsart Univ., Bangkok, Thailand

W. H. Patrick, Jr.

Lab. for Wetland Soils and Sediments, Louisiana State Univ., Baton Rouge, LA 70803

*Corresponding author.

ABSTRACT

Rice (Oryza sativa L.) yields on acid sulfate soils, which comprise a sizable portion of the rice-growing area in Southeast Asia, are constrained by soil parameters. The objective of this study was to identify those parameters most strongly related to rice growth. Metal availability and uptake by rice were evaluated in the Central Plains of Thailand using 134 flooded acid sulfate soils and in a growth chamber utilizing 50 of them. Nutrient-uptake data indicated that uptake of divalent cations was most closely correlated to the divalent activity ratio (A_metal). Although many individual parameters were correlated with rice growth, results from multiple correlation analysis indicated that A_Fe (the ratio of Fe²⁺ activity to the sum of the activities of all other divalent cations), pH, and ionic strength provided the best three-variable model describing dry-matter production in the growth-chamber study. In the field, the best two-variable model describing yields included pH and A_Fe. Therefore, the most important constraints to rice growth on acid sulfate soils were (i) acidity, which includes the combined effects of pH, Al toxicity, and P deficiency, and (ii) Fe stress, which is due to the combined effects of Fe toxicity and deficiencies of other divalent cations such as Ca. This study indicates the importance of divalent activity ratios such as A_Fe when studying metal uptake or modeling plant growth. In a micronutrient fertility trial conducted under greenhouse conditions, the only significant yield response occurred when Si was applied to a limed acid sulfate soil.

Contribution from the Lab. for Wetland Soils and Sediments, Louisiana State Univ., Baton Rouge.

Received for publication August 25, 1988.