Water integration in the clonal emergent hydrophyte, Justicia americana: benefits of acropetal water transfer from mother to daughter ramets

作者：Touchette Brant W^*; Moody John W G; Byrne Caitlin M; Marcus Sarah E

来源：Hydrobiologia, 2013, 702(1): 83-94.

DOI：10.1007/s10750-012-1309-4

• Drought
• Genet
• Plant-water relations
• Ramet
• Translocation
• Water potential

Clonal plant growth is common in aquatic freshwater plants and their success is largely attributed to the sharing of resources (e.g., photosynthates, minerals, and water) within the greater genet. The flow of materials within the clone is largely driven by source-sink dynamics, and in established genets may involve acropetal and/or basipetal flow. During the production of new ramets, however, the mother often provides needed resources to the daughter through acropetal flow. In this study, we consider the role of water sharing in a clonal hydrophyte, Justicia americana, when soil moisture levels around the daughter plant declined. The results of this study indicate that acropetal water sharing is an important function between mother and daughter ramets in this species, as indicated by sustained growth and higher survival in connected daughters residing in water-deprived soils. Interestingly, mother plants, when connected to a drought daughter, began to develop similar xeromorphic features (e.g., greater leaf succulence) even though the parent remained in flooded conditions. We suspect that some physical or chemical signal was conveyed from the daughter to the mother that "forecast" water scarcities, which could prepare the entire genet for potential drought conditions.

• 出版日期2013-2