Involvement of auxin in the responses of wheat germination to salt stress

The effects of salt stress and auxin on germination factors of three wheat cultivars viz. Sepahan, c-84-8, and c-83-1 were studied under controlled conditions. Germination was assessed using three replicates of 25 seeds in a factorial lay out in Completely Randomized Design (CRD) testing combinations of three levels of salinity (0, 4, and 8 dSm-1 NaCl) and three levels of auxin (0, 0.5, and 1 ppm IAA) on seeds of three wheat cultivars in 9 cm diameter Petri dishes. Results showed that increasing concentrations of NaCl reduced germination percentage, radicle length, plumule length, seedling fresh and dry weight, and plumule dry weight. Plumule dry weight increased in seeds only at 4 dSm-1. Auxin increased plumule length, seedling fresh and dry weight, and plumule dry weight, but did not influence seed germination percentage and radicle length. C-84-8 cultivar showed high seed germination percentage, radicle length, and plumule length in comparison to other cultivars while c-83-1 cultivar had high radicle dry weights and Sepahan cultivar produced high seedling fresh and dry weights.