In a pot study, flooding reduced growth of loblolly pine (LP) seedlings and caused an imbalance of nutrients, particularly Fe, in the tops. Swamp tupelo (ST) suffered none of these problems. Also under anaerobiosis, LP roots leaked 85 percent of total ethanol production into solution whereas ST leaked only 55 percent. Application of phosphorus increased LP growth under flooded and drained conditions but ST only under drained conditions. The differential response of the two species to flooding suggests that poor energetics and the leaky nature of LP roots under anaerobiosis restricts its growth in such habitats. Application of phosphorus (P) appears to amend these conditions in LP by reducing moisture stress, reducing nutrient imbalances, and improving energetics in older seedlings. Our results confirm that ST, the hydrophyte, avoids the problems of soil flooding via adaptations in anaerobic metabolism and oxidation of the rhizosphere.
Anaerobiosis Ion imbalance Leaky roots Loblolly pine Nyssa silvatica var.biflora Pinus taeda L. Swamp tupelo