The validity of predawn leaf water potential as an irrigation-timing indicator for field-grown wheat in northern Syria uri icon

abstract

  • We evaluated the validity of predawn leaf water potential (?PL) as an irrigation-timing indicator, using five field-grown wheat cultivars in three moisture regimes in northern Syria. The relationships between ?PL and amount of roots, soil water potential (?Soil), and vapor pressure deficit (VPD) were examined. The effect of the amount of roots on ?PL was only observed before the onset of tillering. The effect of ?Soil was recognized for values below the primary wilting point, and a relationship between nighttime VPD and ?PL was observed above the primary wilting point in some cultivars. However, grain yield decline in the 50% irrigation treatment was not explained by the ?PL change; therefore, the use of ?PL alone is not recommended for determining irrigation timing in the study area
  • We evaluated the validity of predawn leaf water potential (psi(PL)) as an irrigation-timing indicator, using five field-grown wheat cultivars in three moisture regimes in northern Syria. The relationships between psi(PL) and amount of roots, soil water potential (psi(Soil)), and vapor pressure deficit (VPD) were examined. The effect of the amount of roots on psi(PL) was only observed before the onset of tillering. The effect of psi(Soil) was recognized for values below the primary wilting point, and a relationship between nighttime VPD and psi(PL) was observed above the primary wilting point in some cultivars. However, grain yield decline in the 50% irrigation treatment was not explained by the psi(PL) change; therefore, the use of psi(PL) alone is not recommended for determining irrigation timing in the study area. (c) 2005 Elsevier B.V. All rights reserved.

publication date

  • 2006
  • 2006
  • 2006