Depth Effects and Genetic Influences on Injury Caused by Artificial Sea Water Floods to Loblolly and Slash Pine Seedlings

Abstract

Loblolly pine (Pinustaeda L.) and slash pine (Pinuselliottii Engelm.) seedlings from families of full-sib progenies were flooded with a 75% concentration of artificial sea water or with tap water for 2–4 days. The water potential and osmotic potential of the seedlings' needles decreased through 5 days of observations following the sea water flooding, and the contents of chloride and sodium ions increased. Injury and chloride content increased as depth of sea water above the surface of the soil increased. No injury occurred when seedlings were flooded with tap water to similar depths for the same period of time. For the particular families used, slash pine seedlings were more tolerant of sea water flooding than loblolly seedlings, and significant differences in tolerance among families within each species were obtained. Differences in rate of ion uptake and in needle water content were probably responsible for the effects of depth and genotype on injury.