Response of White Cabbage (Brassica oleracea var. capitata) to Single and Repeated Short-Term Waterlogging.

Climate change has a significant impact on the agricultural sector, negatively affecting plants' growth and development, with predicted strong consequences on food availability in the future. Although we are experiencing more frequent and intense heavy rainfall events, a major contributor to field flooding, there is still not much known about the impact of these events on different crops. In this study, we investigated the effects of waterlogging on a model plant white cabbage (Brassica oleracea var. capitata f. alba), with the aim to follow its response to both single and recurrent short-term (72-h length) waterlogging, as well as to track difference in the sensitivity between plants in different growth stages (38- and 48-day-old plants). In our 22-day experiment, settled under fully controlled conditions (16 h day/8 h night, 25 °C day/20 °C night, 60–70% relative air humidity, 250 µmol m⁻² s⁻¹ photosynthetic active radiation), with the aim to more comprehensively recognize consequences of waterlogging on plants, we measured changes in plants on multiple levels: (i) within its morphological traits (number and length of leaves, leaf area, and blade width), (ii) within chlorophyll fluorescence and multispectral traits (20 parameters), (iii) following the levels of plant stress parameters (salicylic acid, abscisic acid, proline, and total polyphenols), and (iv) following changes in the plants' elemental and mineral composition. According to our results, white cabbage was shown not to be very sensitive to waterlogging, with only plants exposed to repeated waterlogging showing signs of the congestion stress. These signs, observed in the changes of molecular stress parameters salicylic and abscisic acids, were not so clearly evident at the aboveground level. We did not observe changes in the plants' morphologies, nor their photosynthetic performance. In addition, removal of waterlogging stress resulted in complete recovery of our model plants, suggesting a prompt adaptation response of white cabbage. With the projected increased frequency of occurrence of flooding events, it will become increasingly more important to recognize crops being highly sensitive to flooding with the aim to try to adapt to the changing climate. [ABSTRACT FROM AUTHOR]