Seasonal Effects of Flooding on Greenhouse-grown Seedling Pecan Trees

Abstract

Seedling pecan tree [ Carya illinoensis (Wangenh) C. Koch] roots were flooded for 28 days while trees were either dormant, beginning budbreak, or in active growth, plus an unflooded control. Flooding roots while trees were dormant did not affect growth and seldom affected leaf elemental concentrations compared to unflooded trees. Trees with roots flooded during budbreak usually had less leaf area and were shorter, with smaller trunks than unflooded trees. Leaf N and Fe concentrations were decreased immediately after flooding, but, 56 days after trees were drained, P, Ca, Mg, Zn, and Mn concentrations were greater than in unflooded trees. Leaf area, tree height, trunk diameter, and leaf and trunk dry weights were not affected by flooding during active growth. Root dry weight was reduced 31% immediately after trees were drained, and 48% 56 days after trees were drained compared to unflooded trees. Trees flooded during active growth had lower concentrations of N, P, K, Ca, Mg, Zn, Fe, and Mn immediately after flooding, but, 56 days after trees were drained, leaf elemental concentrations were not significantly different from unflooded trees.