Root growth and lignification of two wheat species differing in their sensitivity to NaCl, in response to salt stress.
Application of a 100-mM NaCl salt stress to wheat seedlings of a salt-tolerant (Triticum durum var. Ben Béchir) and a salt-sensitive (Triticum aestivum var. Tanit) species decreases the fresh and dry weights of roots especially in the salt-sensitive species, and slightly increases the ratio of dry to fresh weight, especially in the salt-resistant species. All peroxidase activities are increased by salt stress, the water-soluble peroxidase activity being increased much more in the salt-sensitive than in the salt-tolerant species, while the opposite result is observed with the cell-wall peroxidase activity. Some water-soluble peroxidases have been hypothesised to have auxin oxidase activity (which might explain the effect observed on the root biomass), while the cell-wall peroxidases would be involved in lignification. Histochemical observation confirms a more intense lignification in the root cells of the salt-tolerant species compared to the sensitive species, under the effect of NaCl.
Jbir
N
N
Laboratoire de physiologie végétale, département de biologie, faculté des sciences de Tunis, campus universitaire, 1060 Tunis, Tunisie. Najoua.Jbir@fst.rnu.tn
Chaïbi
W
W
Ammar
S
S
Jemmali
A
A
Ayadi
A
A
D007700:Kinetics; D008031:Lignin / Q000378:metabolism*; D010544:Peroxidases / Q000378:metabolism; D018517:Plant Roots / Q000166:cytology / Q000254:growth & development / Q000502:physiology; D012965:Sodium Chloride / Q000494:pharmacology*; D013045:Species Specificity; D013379:Substrate Specificity; D014908:Triticum / Q000187:drug effects / Q000254:growth & development / Q000502:physiology*
D012965:Sodium Chloride; D008031:Lignin; D010544:Peroxidases