TITLE:
Polyamine Metabolism of the Cotton Flower and Its Sub-tending Leaf under Water-Deficit Stress in the Field
AUTHORS:
D. A. Loka, D. M. Oosterhuis, J. D. Mattice, B. L. McMichael
KEYWORDS:
Cotton; Polyamines; Reproductive Stage; Water-Deficit Stress
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.4 No.5A,
May
30,
2013
ABSTRACT: Polyamines,
putrescine, spermidine and spermine are low molecular weight polycations
implicated in flowering and seed set and plants’ responses under adverse
environmental conditions. Research in other crops has shown that polyamine metabolism
is greatly affected by water-deficit stress, however, no information exists on cotton (Gossypium hirsutum L.). A field study was conducted in 2011 in two contrasting
locations (Fayetteville, AR, and Lubbock, TX) in order to investigate the
effect of water-deficit stress during flowering on polyamine metabolism of the
cotton flower and its subtending leaf. Treatments consisted of control (well
watered) and water-stress (irrigation withheld for two weeks at the onset of
flowering) in a split plot design. First day white flowers and their subtending
leaves were collected at the end of each week of the stress period for
determination of polyamine concentrations. Water-deficit stress resulted in
significant increases in PUT and SPD levels of pistils and leaves compared
to the control. However, pistil and leaf SPM content significantly increased
under drought conditions in one location and remained unaltered in the other
one. Leaf and pistil polyamine metabolism of cotton appeared to be greatly
affected by limited water supply, however further research is needed to
elucidate the ways polyamines can be used to increase cotton drought tolerance.