Effects of pH, P, and irrigation frequency on the yields and mineral composition of sugar cane grown under saline conditions
Date
1979
Authors
Contributor
Advisor
Department
Instructor
Depositor
Speaker
Researcher
Consultant
Interviewer
Narrator
Transcriber
Annotator
Journal Title
Journal ISSN
Volume Title
Publisher
University of Hawaii at Manoa
Volume
Number/Issue
Starting Page
Ending Page
Alternative Title
Abstract
In a field experiment the effects of irrigation frequency, S application (pH) and P fertilization on the yields and mineral composition of sugarcane grown under saline conditions were investigated. Sugarcane variety H50-7209 was grown for 11 months in a saline field of Pioneer Mill Co. in Lahaina, Maui, and irrigated with saline water (6 mmhos/cm). Dry weight yields were significantly increased by daily irrigation, P fertilization and S application. Sulfur application reduced the concentration of K and Mg and increased the concentration of Mn in the leaf sheaths. Phosphorus application reduced sheath-Cl concentration, but had no effect on P concentration in the sheaths or 5th internode. Sulfur application also lowered soil pH and reduced exchangeable Mg and K levels, but did not affect exchangeable Na percentage (ESP) or soil electric conductivity (ECe) during the experiment. Heavy rainfall increased soil pH, but reduced ESP and ECe down to the 45 cm depth. Exchangeable Na percentage was more drastically reduced by rainfall when S was applied than when S was not. A greenhouse experiment was conducted with the same sugarcane variety, which was grown in a mixture of equal parts of perlite and vermiculite for 3.5 months. The treatments which were imposed for 2 months, consisted of factorial combinations of three osmotic potentials (OP), 0.05 (control) -2.0 and -4.0 bars established with 2 salts, NaCl and Na2S04; 3 concentrations of P in solution 1.7, 2.5 and 3.3 ppm, and also 2 pH levels, 5.0 and 7.0. Decreasing OP resulted in a significant reduction in dry weight, fresh weight, spindle growth, leaf osmotic potential (leaf ψs) and relative turgidity (RT), but a significant increase in stomatal diffusive resistance (Rs). The effects of OP on these plant parameters were greater with Na2SO4 than with NaCl. Leaf ψs decreased in proportion to OP for both salts indicating complete osmotic adjustment. Evidence of specific ion effects of 804 and/or Na was provided by the greater reduction in growth with Na2SO4 than with isosmotic concentrations of NaCl. Decreasing OP reduced Ca and Mg concentrations in the leaf sheath to deficiency levels. This reduction was greater with Na2SO4 than with NaCl, probably due to reduced uptake of Ca and Mg, as a result of the higher Na concentration in Na2SO4 than NaCl or to lower Ca and Mg activities in the 804 than CI salts.
Description
Keywords
Soils, Salts in, Saline irrigation, Sugarcane--Fertilizers, Sugarcane--Irrigation
Citation
Extent
Format
Geographic Location
Hawaii--Lahaina
Time Period
Related To
Theses for the degree of Doctor of Philosophy (University of Hawaii at Manoa). Agronomy and Soil Science; no. 1320
Related To (URI)
Table of Contents
Rights
All UHM dissertations and theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission from the copyright owner.
Rights Holder
Local Contexts
Email libraryada-l@lists.hawaii.edu if you need this content in ADA-compliant format.