My Account: Log In | Join | Renew
Search
Author
Title
Vol.
Issue
Year
1st Page

Abstract

 

This article in CS

  1. Vol. 49 No. 3, p. 955-960
     
    Received: Sept 24, 2008
    Published: May, 2009


    * Corresponding author(s): trsincl@ifas.ufl.edu
 View
 Download
 Alerts
 Permissions

doi:10.2135/cropsci2008.09.0560

Genetic Variability of Transpiration Response to Vapor Pressure Deficit among Soybean Cultivars

  1. Walid Sadok and
  2. Thomas R. Sinclair *
  1. Agronomy Physiology Lab., Univ. of Florida, Box 110965, Gainesville, FL 32611-0965

Abstract

Simulation studies have demonstrated that the existence of a limitation on maximum transpiration rate (TR) at high air vapor pressure deficit (VPD) in water-limited conditions could result in significant yield increases. A genotype of soybean [Glycine max (L.) Merr.] (PI 416937) has been identified both with a slow-wilting phenotype in the field and limited TR above a VPD breakpoint (BP) of 2 kPa. Until now, there has been no full documentation of any other soybean genotype that has a restriction on TR at high VPD. The objective of this study was to extend the observations on TR response to VPD to a wider genetic base. Seven soybean genotypes were studied: three cultivars of broad genetic background and four new lines of diverse backgrounds with PI 416937 in their pedigrees. Data collected across a VPD range of ∼1 to ∼3.5 kPa for each genotype showed a two-segment TR response to VPD for two cultivars, neither of which was derived from PI 416937. Since three progeny of PI 416937 expressed slow-wilting in the field, these results indicate that the slow-wilting phenotype may also result from a mechanism other than the TR response to VPD. Identification of two new genetic selections with limitation of TR at high VPD indicates there is more than one genetic source for this potentially beneficial trait for water-limited environments.

  Please view the pdf by using the Full Text (PDF) link under 'View' to the left.

Copyright © 2009. Crop Science Society of AmericaCrop Science Society of America

Facebook   Twitter