Premium
Partial versus complete submergence: snorkelling aids root aeration in R umex palustris but not in R . acetosa
Author(s) -
HERZOG MAX,
PEDERSEN OLE
Publication year - 2014
Publication title -
plant, cell and environment
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.646
H-Index - 200
eISSN - 1365-3040
pISSN - 0140-7791
DOI - 10.1111/pce.12284
Subject(s) - aeration , shoot , biology , botany , aerenchyma , photosynthesis , waterlogging (archaeology) , respiration , zoology , polygonum , horticulture , wetland , ecology
The root and shoot tissues of flood‐tolerant wetland plants are highly porous to enable internal gas phase diffusion of O 2 during waterlogging or submergence. In the case of only partial submergence (snorkelling), the atmosphere can act as source of O 2 . The aim of this study was to assess the effect of waterlogging, partial submergence and complete submergence in the dark as well as in light on O 2 partial pressure ( pO 2 ) in roots of R umex palustris (flood tolerant) and R . acetosa (flood intolerant). We used O 2 microelectrodes to measure pO 2 of adventitious roots during manipulations of the water level around the shoot. Root pO 2 in both species declined significantly upon submergence but remained oxic also when shoots were completely submerged in the dark (0.8 and 4.6 kPa in R . acetosa and R . palustris , respectively). The snorkelling effect was substantial in R . palustris only. Submergence in light had less impact on root pO 2 and the effect of snorkelling was also minor. Hence, the benefits of light (underwater photosynthesis) and air contact (snorkelling) upon growth and survival in submerged wetland plants can now be linked to enhanced internal aeration.