Evapotranspiration and yield of wetland rice under non-submerged condition

Date

1991

Abstract

The effect of two methods of irrigation water application, continuous flooding and intermittent irrigation, on evapotranspiration (ET), water use efficiency (WUE), and growth and grain yield of three wetland rice varieties (Oryza sativa L., vars. IR58, IR72, IR74) were studied in a field of experiment with half-drum lysimeters (no sepage and percolation) using a silty clay Typic Hapludoll soil. The stress day index (SDI) approach was used in intermittent irrigation with soil matric potential as the stress day factor. The ratio of the ET of intermittently irrigated lysimeter (ETa) to that of the ET of continuously flooded lysimeters (ETp) was 0.4 to 0.8. The seasonal average ETa were 3.8, 2.5, and 3.6 mm/day while the seasonal average ETp were 6.4, 5.3, and 6.0 mm/day for IR58, IR72, and IR74, respectively. The WUE (mg grain per g water) was similar between moisture regimes, averaging 1.1, 1.6, and 1.1 for IR58, IR 72, and IR74, respectively. A positive linear correlation between biomass production and total water use was observed. Number of tillers and panicles and weight of one hundred grains were similar between irrigation treatments. Plant height and total straw and grain weights were significantly higher with plants under continuous flooding than with intermittently irrigated plants. Yield decreased by 50% when only half of ETp was supplied as irrigation water.

Document Type

Master Thesis

Language

English

LC Subject

Evapotranspiration, Rice

Location

UPLB Main Library Special Collections Section (USCS)

Call Number

LG 995 1991 A2 R44

This document is currently not available here.

Share

COinS