Scientists seek new ways to feed the world amid global warming
Pastor Dale Morgan
Scientists seek new ways to feed the world amid global warming*
LOS BANOS, Philippines, Aug 17 (AFP) Aug 17, 2007
On an agricultural research station south of Manila a group of
scientists are battling against time to breed new varieties of rice as
global warming threatens one of the world's major sources of food.
According to the International Rice Research Institute (IRRI) more than
half the world's 6.6 billion people depend on rice for nourishment.
"Parts of the world will become drier and apparently that's already
happening, and some parts will become even wetter," said Moroccan crop
physiologist Rachid Serraj.
"But most importantly it's going to shift the rainfall distribution.
It's going to become more unpredictable, and that is the problem for
rice cultivation," he said.
Chinese scientist Peng Shaobing wraps his paddy fields with tarp and
blasts them with cold air from air conditioners.
His colleague Indian plant geneticist Kumar Singh grows 2,000 rice
varieties inside giant metal cabinets, the seedlings sprouting above
styrofoam trays soaked with varying degrees of brine to simulate the
seawaters that threaten to engulf rice-growing areas over the next century.
The three IRRI scientists are entrusted with ensuring that the half of
mankind who depend on rice will not go hungry as rising temperatures and
ocean levels threaten one of the world's most important crops.
The Intergovernmental Panel on Climate Change projects the globe will
warm by 0.2 degrees Celsius every 10 years, far higher than the
0.6-degree Celsius rise in the past century, with serious consequences
for food production.
IRRI, based in this university town south of the Philippine capital and
a vital part of the "Green Revolution" that dramatically raised cereal
yields in the 1970s, has gathered top experts to work on "new frontier
projects" to meet the threat.
This is apart from more conventional research to further boost yields,
make the plants more resistant to pests and disease, and make the grain
more palatable.
Rice yields would fall by 10 percent for each one-degree rise in the
minimum temperature at night, time spent by the plant for growth
processes, said crop physiologist Peng, a pioneer researcher in this field.
Between 1978 and 2003 minimum mean nighttime temperatures rose by 1.5
degrees Celsius, suggesting a 15 percent production decline over 28
years, Peng told AFP.
Higher nighttime temperatures shorten the growing time for rice. "The
yield is reduced because the plant doesn't have enough time to grow,"
Peng said. "Higher night temperatures also leads to poorer grain quality."
Drought and salinity are already a major problems. Twenty-three million
hectares (57 million acres), or 18 percent of the world's rice farms are
considered "drought-prone", Serraj said.
A dry spell in hot spots such as eastern India can push up to 15 million
rain-fed rice farmers into poverty in a single year, he said. Even in
China, demand for water from industry and elsewhere is putting pressure
on high-yield irrigated rice grown there, he added.
The two countries account for nearly half the world's rice growing areas.
Next to drought, the influx of saltwater not only in coastal but also
inland farms through careless irrigation practices is the number-two
problem, said Singh.
Some 6.3 percent of the world's soil surface is already considered
saline, and global warming or not, the problem affects most of the rice
fields of South Asia and Southeast Asia, he told AFP.
Global warming is projected to cause sea levels to rise by between 10
and 85 centimetres (four and 34 inches) over the next century, which
would threaten key rice-growing areas in Vietnam, Indonesia, Bangladesh,
and India among others.
For the IRRI scientists, the challenge is to produce new breeds and
innovate crop management techniques to help farmers meet the triple
threat of drought, higher temperatures, and soil salinity, along with
the new pests and diseases that will crop up as rice is grown in
radically new environments.
Peng said high-yield varieties developed by IRRI seem to have higher
tolerance for warmer nighttime temperatures. His experiments seek to
determine their yields in simulated cooler night temperatures.
Breeding improved varieties, a process that begins at IRRI and other
laboratories and involves crossing the desirable genes of the 110,000
varieties at the IRRI gene bank here, ends with their dispersal to the
farmer end-users.
The process used to take about 15 years, but Singh said it can now be
done as fast as six years.
It now takes between 3,000 and 5,000 litres (780 and 1300 US gallons) of
water to produce one kilogram (2.2 pounds) of rice, but IRRI is trying
to breed maize qualities into rice so farmers could also grow them on a
dry field.
So which side is winning the race so far, climate change or the
scientists? The research is being hampered by a funding crunch that has
hit IRRI.
"At this stage, I think it is equal, but if we're not going to increase
our support, we're going to lose the battle," Peng said.
Pastor Dale Morgan
Scientists seek new ways to feed the world amid global warming*
by Staff Writers
Los Banos, Philippines (AFP) Aug 17, 2007