Responses of Lilium hybrid 'Brindisi' to varying periods of waterlogging at vegetative stages

Abstract

Lilium species with ornamental, edible, and medicinal values are distributed all over the world. Little is known about the responses of Lilium genotypes to waterlogging stress. Lilium hybrid 'Brindisi' was used to study the physiological responses of roots, bulbs, and leaves to 1, 2, 4, 8, and 13 d of waterlogging stress. Results showed that waterlogging stress seriously hindered the transport of nutrients from bulbs to stems and leaves. The physiological indicators could be divided into two categories. The first category was the physiological parameters indicating plant damage. The dry and fresh masses of stems and leaves, chlorophyll (Chl) a, Chl b, Chl a+b, and carotenoid content decreased, the dry and fresh masses of bulbs, malondialdehyde and H2O2 content increased under waterlogging stress. The other category was the physiological indicators that regulate the plant adaptability to waterlogging stress. Among them, superoxide dismutase and pyruvate decarboxylase activity changed little, proline content increased significantly, soluble sugar and protein content, and ascorbate peroxidase (APX), catalase (CAT), alcohol dehydrogenase, and lactate dehydrogenase activities increased in the early stage, and decreased in the later stage of waterlogging stress. The turning point of these physiological parameters was 4 - 8 d after waterlogging stress. Bulbs played an important role in alleviating flooding stress in the early stage of waterlogging. APX and CAT also played an important role in eliminating ROS in the early stage. This research lays foundation for the research on the mechanism of waterlogging tolerance and breeding of waterlogging-tolerant cultivars of Lilium spp.