Physiological effects of ethylene and salicylic acid on germination improvement and CTR1 and NPR1 gene expression and some of the Physiological features of the degraded seed of Glycine max (L.)

Glycine max is one of the important oilseed plants in all of the world. One of the problems of G. max production is seed deterioration and low germination and vigor during seed storage and before planting time. To investigate the effects of deterioration on seed and the effects of salicylic acid and ethylene on the improvement of the deteriorated seed of G. max were conducted accelerated aging test for 0, 6 and 10 days and a natural aging test for 6 months. After aging conditions, seeds were imbibed with 50 M salicylic acid and 10 M ACC (precursor of ethylene) for 6 hours at 25 °C. Also, a bach of seed after the natural and accelerated aging test was used without any hormonal treatment as a control seed (called dry seed). Germination percentage, the enzyme activity of catalase, superoxide dismutase, glutathione peroxidase, total protein, and malondialdehyde were measured. Gene expression of CTR1 and NPR1 were investigated on dry seed and under imbibitions of water, salicylic acid and ACC at 6, 12 hours with the Q-RT-PCR method. Seed germination decreased. Amount malondialdehyde increased and total protein decreased. Enzyme activities of catalase, superoxide dismutase and glutathione peroxidase were decreased. and electrical conductivity increased with the progress of aging. Gene expression varied on different days and different hours. Salicylic acid and ACC had different effects on measured traits. All together aging caused disturbing of seed physiology and salicylic acid and ACC were not able to improve deteriorated soybean seed.