Please use this identifier to cite or link to this item:
|Title: ||Strategies for Improving the Water Use Efficiency of Rice|
|Authors: ||Thompson, John|
|Issue Date: ||19-Oct-2005|
|Series/Report no.: ||Program 1|
|Abstract: ||The cost of irrigation water accounts for 30-38% of the total variable costs of rice
production in the Murray and Murrumbidgee Valleys. Rice production consumes a
substantial proportion of the available supply of irrigation water. Any water
management practice that has the potential to reduce water use and/or increase water
use efficiency should be investigated.
This project evaluated two approaches that may increase water use efficiency of rice –
delayed flooding and a water management strategy termed mid-season ‘drain’. Water
use was quantified and agronomic performance of the rice crop monitored.
Delayed flooding involves intermittent irrigation of the crop until about ten days prior
to panicle initiation. The scheduling (and number) of intermittent irrigations will be
determined by the growing season temperatures. In the experiments reported here the
combine sown treatments received eight irrigations as well as the first flush which
initiated germination. The aerial sown treatments received three or four irrigations
once the crop had established. The time taken for establishment (3-4 leaves) ranged
from 34-43 days.
Mid-season ‘drain’ involved removing surface water from the crop for about seven
days towards the end of tillering. The rice plants experience visible moisture stress
before the flood is re-applied.
Plots grown with delayed flooding produced equivalent yields to the fully ponded
control. Water use was reduced by 8-18%; thus water use efficiency was increased.
Mid season ‘drain’ increased grain yields by 6, 10, and 9% for the three growing
seasons covered in this report. Whilst none of these increases in yield were
statistically significant there is sufficient evidence of an increase in grain yield when
the crop experienced a mid-season ‘drain’ to warrant further investigation.
In commercial crops, when mid-season ‘drain’ is practised, a reduction in water use of
about 50 mm (0.5 ML/ha) could be expected.
Results from this project and from project 1204(A) indicate that where water use is
the total water balance ie. includes rainfall and change of storage in the soil profile,
water use efficiency from a fully ponded crop is unlikely to exceed 7.5 kg/ha/mm
|Type of Work: ||Other|
|Appears in Collections:||Research Papers|
This work is protected by Copyright. All rights reserved. Access to this work is provided for the purposes of personal research and study. Except where permitted under the Copyright Act 1968, this work must not be copied or communicated to others without the express permission of the copyright owner. Use the persistent URI in this record to enable others to access this work.
|P1204BFR06-05.pdf||67.91 kB||Adobe PDF|
Items in Sydney eScholarship Repository are protected by copyright, with all rights reserved, unless otherwise indicated.