Tolerance to waterlogging and flooding of rapeseed | Umweltbundesamt

The heavy rainfall events that occur as a result of climate change lead to waterlogging and flooding of agricultural crops. The reduced availability of oxygen and carbon dioxide under water leads to an energy crisis in the plant cells, which leads to growth disorders and consequently to harvest losses. Most crops, especially rape, are very sensitive to this stress.

In the first two years of the project, screening experiments were carried out with 18 Bavarian rape varieties and 7 Asian varieties to determine differences in the stamina tolerance. Experiments were carried out in the greenhouse on 6-week-old rapeseed plants and on young plants in the climatic chamber and on germinating seeds. In addition to growth parameters, ADH activities in plant roots were also determined. The results showed large variations between individuals, and there were differences in the screening methods. For this reason, none of the European varieties could be described as reproducibly more tolerant or sensitive. Not all Asian varieties classified as tolerant or sensitive could be confirmed. 

In the third year of the project, two varieties were selected, a European winter rapeseed and an Asian semi-winter rapeseed. Significant differences in the tolerance between these varieties we have not observed so far. For these varieties, after treatment with waterlogging and flooding, the molecular stress response was analyzed by RNAS sequencing. The evaluation of the data is still ongoing. Significant stress reactions can be observed in both genotypes, the data will serve to show the general response of oilseed rapeseed. Similarly, there are differences between varieties that still need to be functionally characterized and that may be associated with differences in the response to waterlogging and flooding.