Water Management

KEY CHECK 6:
AVOIDED STRESS CAUSED BY DROUGHT
OR EXCESSIVE WATER THAT COULD AFFECT
THE GROWTH AND YIELD OF THE CROP.

The right volume of water promotes better nutrient uptake, good plant vigor, better snail and weed management, uniform growth and maturity, and more efficient farm operations.

Insufficient water causes drought stress that results in low fertilizer efficiency, and low yield and low rain quality. Excessive water results in higher irrigation cost (if using pump), nutrient imbalance, low yield, and more greenhouse gas emissions.

ASSESSMENT OF KEY CHECK

No symptoms of water stress due to drought from seedling through the dough grain stages.

No symptoms of water stress due to excessive irrigation water during the vegetative phase.

Symptoms of water stress during the vegetative phase:
Drought stress (deep soil-cracking for more than three days):

Leaf rolling and leaf tip-drying
Stunted growth

Excessive water stress (>5cm water depth for seven days or more):

Reduced tillering (<10 tillers per hill)
Smaller leaf area
Roots are dark-colored instead of reddish brown or lighter

Symptoms of water stress due to drough during the panicle initiating to grain-filling stages:

Leaf-rolling and leaf-tip drying
Many unfilled spikelets
Reduced panicle exsertion

RECOMMENDATIONS TO ACHIEVE KEY CHECK

Achieve 3-5 cm water level every irrigation time from early tillering until 1-2 weeks before harvest, except during the flowering stage when 5-7cm water level should be maintained.If DWSR, suspend irrigation for 0-14 DAS, unless severe drought symptoms appear.
Drain water or stop irrigation:
- One week before expected date of harvest for medium-textured soil or during DS
- Two weeks before expected date of harvest for fine-textured soil during WS.
If water is scarce, practice controlled irrigation. During crop growth, practice the alternate Wetting and Drying (AWD) technology aided by an observation well.