Wageningen scientists find genetic “control box”
Plant breeding will probably be capable to develop potato plants with a better drought-tolerance than the currently grown plants. This appears from research on which Anitha Kumari took her doctoral degree at Wageningen University, part of Wageningen UR, in March 2011. Kumari found large differences in the extent to which potato plants were recovering after a period of drought. She also discovered that there is one specific area on the potato chromosomes where the genes are located that are regulating drought tolerance in her potatoes.
Photograph: Potato species show enormous differences in their drought tolerance (click photograph for larger version)
Potatoes are very efficient in utilising water. A potato plant is, e.g., producing much more food per litre groundwater than a wheat plant. Problem, however, is that potato plants are not good at dealing with low water availabilities; tuber yields are decreasing rapidly under such conditions. The findings of Kumari show that it is probably quite well possible to develop potato plants that are not only efficient in utilising water but that are also showing a good recovery while producing sufficient food after a dry period.
The Wageningen scientist was the first to conduct a large-scale study into the role of genetic properties of potato plants in reaction to drought.
For her research Kumari used a crossing of two genetically very different potato plants; they had two different wild potato species as ancestors. She grew plants from the progeny of the crossing of these two potatoes under dry conditions for about three weeks after which the plants were watered. Some potato plants recovered whereas others died. This shows that there is a real perspective of developing potatoes with a better drought tolerance.
During these experiments Kumari investigated which genes of the potato plant were more or less active at the start of the drought period. She discovered that no less than thousands of genes responded specifically to drought.
Genetic analysis of the potato plants by Kumari showed that differences in activity of thousands of genes are dependent of one area in the DNA of the investigated potatoes. This effect was only visible during drought and not under normal conditions. This leads her to conclude that the reaction of the plant to dry conditions is probably regulated in this area of the DNA.