Physiological responses and effective selection criteria of drought tolerant plants

Abstract

Aim : The present study was carried out to establish the method for screening drought tolerant Korean native plants and to analyze the appearances of drought tolerant Korean native plants on drought stress. Methodology : Twelve Korean native plant species (Sala scilloides, Commelina communis, Hemerocallis fulva, Bupleurum latissimum. Hosta plantaginea, Iris dichotoma, Lysimachia barystachys, Viola mandshurica, Amphicarpaea bracteata. Aeschynomene indica, Dianthus chinensis and Urtica thunbergiana), which were 16-week-old seedlings, were exposed to drought stress by stopping irrigation to observe phenotypic, physiological and biochemical responses. Results : Based on the withering rates under drought condition, the plants were classified into three groups; drought tolerant (S. scilloides, C. communis. H. fulva, B. latissimum, H. plantaginea and I. dichotoma), normal (L. barystachys. V mandshurica and A. bracteata) and sensitive (A. indica. D. chinensis and U. thunbergiana) group. While chlorophyll contents of the plants were generally decreased in the drought condition, the extents of decrement in the sensitive group were larger than in the tolerant group. RWCs in the tolerant group were higher than in the other groups on the same periods of drought condition. Proline and soluble reducing sugars accumulated in the sensitive group much earlier than in the tolerant group. Interpretation : The results revealed that S. scilloides, C. communis, H. fulva. B. latissimum, H. plantaginea and I. dichotoma were screened as drought tolerant plants and the established method in the study can be applied to screen drought tolerant plants for Korean natives.