4.  Drought and flood tolerant crops

Agriculture of any kind is strongly influenced by the availability of water. Climate change will modify rainfall, evaporation, runoff, and soil moisture storage. Changes in total seasonal precipitation or in its pattern of variability are both important. The occurrence of moisture stress during flowering, pollination, and grain-filling is harmful to most crops and particularly so to corn, soybeans, and wheat. Increased evaporation from the soil and accelerated transpiration in the plants themselves will cause moisture stress. As a result, there will be a need to develop crop varieties with greater drought tolerance.

Yet in putting their knowledge and skills to better use, dryland farmers can blend with science - another key to successfully combating desertification. The Alliance of Future Harvest Centres of the CGIAR and their partners generate and mobilise cutting edge science for dryland agriculture. The Centres pursue an integrated genetic and natural resource management (IGNRM) approach, which synergises the disciplines of biotechnology, plant breeding, agronomy, and social sciences with rural empowerment at its core.

The Alliance of Future Harvest Centres of the CGIAR has been using a portfolio of breeding methods to develop drought-tolerant crops for the drylands. For instance, ICRISAT has achieved important gains in improving drought and disease resistance in millet and sorghum, as well as in the leguminous crops chickpea, groundnut, and pigeon pea. These are hardy crops that are a bulwark against hunger and a major source of livelihoods in the drylands. Moreover, India, Nepal, Pakistan, and China are rapidly taking up improved pigeon pea and chickpea varieties sourced from ICRISAT.

The International Rice Research Institute (IRRI) has been developing resilient rice varieties that can withstand drought yet give high yields. The Institute also introduced aerobic zero-tilled rice. Through this intervention, the highly water- and labour-demanding conventional puddle transplanting is replaced with zero-tilled direct-sowing systems of rice. This saves 35-40 per cent irrigation, without decreasing yields. The IRRFs projects are helping dryland farmers in the Indian subcontinent to improve productivity and fight drought. [1]
 
Farmers should soon have access to a new strain of flood-resistant rice, say scientists.
The development was discussed at the 3rd steering committee meeting of the Irrigated Rice Research Consortium of the International Rice Research Institute (IRRI) in Hanoi, Vietnam last week (8-9 October).
 
A large portion of Asian rice land is located in deltas and low-lying areas that are at risk from flooding during the monsoon season, and climate change intensifies these risks, said Reiner Wassmann, coordinator of the Rice and Climate Change Consortium of IRRI.

Crop scientists estimate that annual flooding leads to losses worth US$1 billion across south and South-East Asia.
 
Wassmann told SciDev.Net that a flood-resistant rice variety called Swarna Submergence 1 should reach farmers by 2009. The plant carries the sub1a gene that enables it to be submerged for up to 17 days. [2]
 
Climate change is making crop scientists review their research agenda. Until now, their main focus was on improving yields. But with successive International Panel on Climate Change (IPCC) reports warning that increased droughts and floods will shift crop systems, 'climate-proofing' of crops has become crucial. The Consultative Group on International Agricultural Research (CGIAR) institutes are now investigating how to make crops' more resilient to environment stresses.

But efforts are hampered because few climate models predict changes for individual regions, making it difficult to predict how climate change will affect growth and yields of specific crops in each region. [3]
 
Reiner Wassman, Coordinator of the Rice and Climate Change Consortium at the International Rice Research Institute (IRRI) in the Philippines, says IRRI strategies should include breeding rice that can survive climate change. He wants to see plants that can tolerate higher temperatures and/or flooding, that flower in the mornings before temperatures rise, and that transpire (lose water through evaporation from leaves) more efficiently to cool the air around them. [4]

Despite reservations in other parts of the world genetic modification is becoming one of the staple tools of researchers aiming to enhance developing world agriculture. "I can understand the opposition to GM, and I sympathize to a certain extent with it," said Dr Verchot. "But in developing countries we're dealing with a crisis situation; and whatever tool is available, we need to apply it to that situation." [5]
 
We can grow the variety of genetically modified crops that can be resistant to floods and droughts we still need to encourage research on GM. Studying only micro aspects will not help. There is threat of losing biodiversity of crops. (Also see Maintaining Bio-diversity.) We need to integrate both traditional and modern knowledge. Genetic manipulation is not all as bad as we think the only problem with it is careless sanction to variety of GM crops without much thinking of its consequences. There is need for long term research on GM crops. Apart from genetic modification of seeds and crops, there are traditional ways of growing food in flooded land or in drought prone areas. One is rice and prawn farming in low lying coastal districts of Kerala and the other is sand mulching in drought prone area. These two cropping patterns prove that genetic manipulation is not the only way of climate change adaptation. These methods are not hi-tech methods. A little bit of understanding of the environment around us helps develop such methods. [6] [7]