Sunday, November 1, 2009

Rice science, a must to cope with climate change

Rice science, a must to cope with climate change


Agri-Commodities
Written by Ramon Efren R. Lazaro / Correspondent

Tuesday, 20 October 2009 20:36
PHILRICE, Nueva Ecija—As the country reels from the devastation brought about by typhoons Ondoy and Pepeng, experts blame climate change.
Rice experts from the Philippine Rice Research Institute (PhilRice) explain that climate change is now upon us. We need not wonder why our weather is very erratic.
PhilRice experts claim that intense heat is a manifestation of climate change. Heat affects humans, animals and crops alike, especially rice.
Studies and crop-simulation models show that rice yield is expected to decrease by 10 percent to 15 percent for every 1°C increase in temperature. Heat stress is not good for the rice plant because it reduces tillering, height, number of grains and grain filling, which eventually lead to reduced yields, they added.
The Department of Agriculture-PhilRice and the International Rice Research Institute (IRRI) are into breeding drought-, saline-prone and submergence-tolerant rice varieties.
Heat-tolerant rice breeders are identifying possible parents from Pakistan, Iran and Saudi Arabia rice varieties. These countries have rice varieties that can thrive under high temperatures. From the best of these varieties, heat-tolerance traits will be transferred into popular local varieties.
Submergence breeding efforts have resulted in NSIC Rc194 (Submarino I), which can survive up to 10 days of submergence in water during its vegetative stage.
Varieties Rc 182, 184, 186, 188 and 190 are saline-tolerant. Rc192 is drought-tolerant.
Seeds of these climate change-adapted varieties are being multiplied for massive use by 2010.
The controlled irrigation (CI) technology that saves water in irrigated rice farms is now being promoted. Some 16-percent to 35-percent reduction in water use is possible through CI without significantly reducing grain yield.
Research studies on varieties that require less water are also in the pipeline. CI also saves on labor and input costs, and reduces methane emission.
State-of-the-art technologies like geographic information system and remote sensing also help identify and map vulnerable areas like drought-prone areas in the country. Studies like these are good inputs in recommending crops that can be planted in specific areas to optimize land use.
The use of information and communications technology can be incorporated as a tool to bridge the knowledge gap between farmers and climate-change adaptation and mitigation measures.
Rice emits methane, a greenhouse gas. Earlier research by DA-PhilRice, in collaboration with IRRI, identified ways to lessen methane emission in the rice field.
These include use of ammonium sulfate as nitrogen fertilizer in place of urea; use of phosphogypsum when applied in combination with urea fertilizer; midseason drainage; and direct seeding instead of transplanting.
The use of the leaf color chart also lessens the use of nitrogen fertilizer, one source of nitrous oxide greenhouse gas.
Being a diversified integrated rice-based farming system, Palayamanan reduces production risks brought about by climate change.
It reduces the use of chemical fertilizers through its biomass resource-recovery component. It increases or enhances sinks of CO2 through cropping intensity, planting of fruit trees and establishment of a miniforest.
It is also a location-specific system that depends on the environment, like weather and soil characteristics.
Because the effects of climate change are location-specific, this program is one good approach in mitigating climate change. National technology recommendations can now be downscaled to regions, provinces, municipalities, or even barangays and be based on existing soil conditions, weather patterns and climate trends of a certain contiguous area.
Likewise, proposals for adaptation and impact mitigation of climate change are works in progress. Present technologies will be reviewed to come up with a holistic approach on how to cushion the effects of climate change. The use of weather and climate information to safeguard and maximize yield will be encouraged.

No comments: