Effect of waterlogging on growth and yield of sunflower, Helianthus annuus L.

摘要

Excess moisture at any growth stage is detrimental to any crop. Waterlogging results in major yield loss in sunflower even when not accompanied by high salt levels. When wet, the heavy clay soils on which sunflower is mostly grown have poor aeration and poor internal drainage (Weiss, 2000). Sunflower is sensitive to poor soil aeration (Blarney ef al., 1997). The response of plants to waterlogging is usually considered to be dependent on genotype, environmental conditions, stage of development and theduration of waterlogging (Russel 1959; Cannell 1977). Leaf expansion and stem extension of sunflower decreased with waterlogging for nine days at the six leaf and bud visible stages (Orchard and Jessop, 1984; Orchard and So, 1985). Waterlogging atanthesis resulted in complete crop failure (Orchard and So, 1985). Therefore a pot culture experiment was conducted to quantify the effect of waterlogging at various growth stages on growth and development of sunflower.