An international team led by researchers at the University of California, USA, has genetically engineered crop plants that survive droughts, and can grow with 70% less irrigation water. This development should be a fitting reply to the doomsday prophecies of the weather scientists, who warn that climate change may result in more frequent and widespread droughts, with serious implications for agriculture and worldwide food security.
The research team is hopeful that ?similar results will be found in crop plants such as tomatoes, rice, wheat, canola, and cotton. Upon completion of greenhouse experiments, the researchers plan to carry the research forward into field trials,? reports the International Service for the Acquisition of Agri-biotech Applications (ISAAA).
The researchers could suppress the programmed death of leaf cells and equip the plants to survive severe drought conditions. They chose tobacco as an experimental plant, ?because it is big, fast growing, and a good model for many other crop plants,? they said.
The researchers inserted into the tobacco plants, a gene that interrupted the biochemical chain of events that normally leads to the loss of the plant’s leaves during drought.
The genetically modified tobacco plants, and the non-modified plants in the experiment’s control group, were all grown in a greenhouse under the same optimal conditions for 40 days. Water was then withheld from all of the plants for 15 days, simulating extreme drought conditions.
During the dry period, the non-modified tobacco plants in the control group wilted, lost their green pigment, and progressively deteriorated. The genetically modified plants, however, remained green, and did not display signs of severe deterioration.
At the end of the 15-day induced drought, all of the plants were re-watered for one week. The plants in the control group all died, but the genetically modified plants recovered and resumed normal growth, with little reduction in seed yield.
?Surprisingly, although the genetically modified tobacco plants went more than two weeks without being watered, they maintained a relatively high water content and continued their photosynthetic activity throughout the dry period,? said researcher Rosa Rivera.
?In short, with only minimal reduction in yield, these plants survived on just 30% of the normal irrigation water – severe drought conditions that killed all of the plants in the control group,? she said.