Improved tolerance of wheat plants (Triticum aestivum L.) to drought stress and rewatering by the arbuscular mycorrhizal fungus Glomus claroideum: effect on growth and cell membrane stability

BELTRANO, J.; RONCO, M. G.

BRAZILIAN JOURNAL OF PLANT PHYSIOLOGY

Lugar: Brazilian Society of Plant Phisiology ; Año: 2007 vol. 20

1677-0420

The aim of this paper was to investigate the contribution of the arbuscular mycorrhizal fungi Glomus claroideum to water stress tolerance. The water stress plant tolerance was determined through dry weight, relative water content, leakage of solutes and leaf chlorophyll and protein contents in mycorrhizal and no-mycorrhizal wheat plants growing under controlled conditions, submitted to moderate or severe water stress and rewatering. Dry weight, relative water content and leaf chlorophyll contents were significantly higher in mycorrhizal plants after severe water stress and rewatering treatments, compared with non-mycorrhizal ones, while electrolyte leakage was significantly lower in water stressed and re-watered inoculated plants. When the irrigation was re-established, the mycorrhizal plants showed an increase in total dry weight and chlorophyll contents, and recover the cellular membrane permeability in leaves compared with non-mycorrhizal plants. The higher dry weight, chlorophyll and relative water contents and lower cellular solute leakage of mycorrhizal plant leaves under severe water stress conditions, compared with nonmycorrhizal plants, showed that root colonization by G. claroideum can alleviate the deleterious effects of drought stress and retard the senescence syndrome in wheat.Glomus claroideum to water stress tolerance. The water stress plant tolerance was determined through dry weight, relative water content, leakage of solutes and leaf chlorophyll and protein contents in mycorrhizal and no-mycorrhizal wheat plants growing under controlled conditions, submitted to moderate or severe water stress and rewatering. Dry weight, relative water content and leaf chlorophyll contents were significantly higher in mycorrhizal plants after severe water stress and rewatering treatments, compared with non-mycorrhizal ones, while electrolyte leakage was significantly lower in water stressed and re-watered inoculated plants. When the irrigation was re-established, the mycorrhizal plants showed an increase in total dry weight and chlorophyll contents, and recover the cellular membrane permeability in leaves compared with non-mycorrhizal plants. The higher dry weight, chlorophyll and relative water contents and lower cellular solute leakage of mycorrhizal plant leaves under severe water stress conditions, compared with nonmycorrhizal plants, showed that root colonization by G. claroideum can alleviate the deleterious effects of drought stress and retard the senescence syndrome in wheat.G. claroideum can alleviate the deleterious effects of drought stress and retard the senescence syndrome in wheat. Key words: mycorrhizae, relative water content, rewatering, solute leakage, water deficit.mycorrhizae, relative water content, rewatering, solute leakage, water deficit.