ARS | Publication request: Delta 13C predicts water deficit sensitivity in Malus sieversii (Ledeb.) M. Roem. from a xerophytic site in Kazakhstan

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: December 29, 2010
Publication Date: January 1, 2011
Citation: Bassett, C.L., Glenn, D.M. 2011. Delta 13C predicts water deficit sensitivity in Malus sieversii (Ledeb.) M. Roem. from a xerophytic site in Kazakhstan [abstract]. Northeast Region-American Society for Horticultural Science Annual Meeting. p. 17.

Technical Abstract: Modern apples [Malus x domestica (Borkh.)] are thought to have originated in western China from the progenitor species, Malus sieversii (Ledeb.) M. Roem. Due to many generations of selection for traits associated with high fruit quality, our current breeding germplasm has become dangerously narrow. Genes for other useful traits such as disease and insect resistance, cold hardiness, and drought tolerance are quite limited within our breeding populations. To expand our repertoire of stress responsive genes that can be used to improve drought tolerance and/or water use efficiency (WUE) in our current apple varieties, we have screened a population of M. sieversii isolated from a xerophytic site in Kazakhstan. Using delta 13C as a surrogate measurement of WUE to select M. Sieversii individuals with extreme WUE values, we clonally propagated GMAL4002.e and GMAL3685.e (both low WUE values), along with a commercially important cultivar ('Royal Gala') to serve as a standard for comparison. In a preliminary experiment, the lowest WUE line (GMAL4002.e) showed signs of early wilting after water was withheld from the pots for six days. 'Royal Gala', GMAL3685.e, and well watered controls from each line showed no signs of wilting during this time.