Divergences in hormonal and enzymatic antioxidant responses of two Chicory ecotypes to salt stress.

To evaluate the effect of salt stress on seed germination, early growth, antioxidant enzymes activity and ABA content of chicory ecotypes (Cichorium intybus) a factorial experiment was conducted at College of Agriculture, Shiraz University in 2014 based on completely randomized design with four replications. The treatments comprised five salinity levels (tapwater, 3, 6, 9, 12 dS m(-1)) of sodium chloride on Shirazi-black and white chicory ecotypes. The results showed that germination characteristics and primary seedling growth were decreased in both ecotypes with increasing in salinity severity. The effects of salinity on radicle and plumule length as well as seedling weight were the same as its effects on seed germination. The effect of salt stress on antioxidant enzymes activity (especially catalase) and ABA content were significant which they were enhanced with increasing salinity level; Black ecotype performs better than the white one under high salinity, as indicated by a lower decreasing in germination characteristics and primary growth and higher antioxidant enzymes activity as well as ABA content. These facts should be taken into consideration in the economic cultivation of this valuable horticultural and medicinal plant and this data would be useful for the crop breeding projects.