The effect of multiple abiotic stresses (drought and heat shock) on plants
A
combination of drought stress and heat shock is encountered by many
field-grown plants and crops in the US and abroad. This combination can
have a severe detrimental effect on plants resulting in reduced growth
and productivity, or death. Although drought stress and heat shock have
been extensively studied, little is known about how their combination
impact plants. Preliminary results from Arabidopsis and tobacco suggest
that the physiological and molecular response of plants to a
combination of drought stress and heat shock is distinct from that of
plants subjected to each of these stresses applied individually. We
hypothesize that the response of plants to a combination of drought
stress and heat shock is controlled by a set of regulatory genes
specifically induced or activated during a combination of drought
stress and heat shock. Furthermore, we hypothesize that some of these
genes can be used to enhance the resistance of plants and crops to a
combination of drought stress and heat shock. Using array technology
and RNA blots we are performing a comprehensive analysis of gene
expression in Arabidopsis and tobacco plants subjected to a combination
of drought stress and heat shock. We are identifying different
regulatory genes specifically involved in the response of plants to
this stress combination, and test their function with knockout plants
and overexpressors.
Rizhsky, L., Hongjian, L. and Mittler, R. (2002) The combined effect of drought stress and heat shock on gene expression in tobacco. Plant Physiol. 130, 1143-1151.
Rizhsky L., Liang H., Shuman J., Shulaev V., Davletova S. and Mittler R. (2003) When defense pathways collide: The response of Arabidopsis to a combination of drought and heat stress. Plant Physiol.134, 1683-1696.
Suzuki N, Rizhsky L, Liang H, Shuman J, Shulaev V, Mittler R (2005) Enhanced tolerance to environmental stresses in transgenic plants expressing the transcriptional co-activator MBF1. Plant Physiol. 139, 1313-1322.
Mittler. R (2006) Abiotic Stress, the Field Environment and Stress Combination. Trends Plant Sci. 11, 15-19