Drought is one of the key limiting factors that adversely affects the growth and productivity of crop plants. For the enhancement of drought tolerance in crop plants, the identification of basic mechanisms of a plant to drought stress is necessary. In this study, we compared physiological and biochemical responses of five local Arundenilla hirta ecotypes to drought stress. These ecotypes were previously collected from various parts of Korean peninsula, including Youngduk, Gunsan, Jangsoo, Jinju-1 and Yecheon. A. hirta plants were exposed to drought stress for 14 and 17 days respectively, followed by re-watering for 3 days. The results showed that the lipid peroxidation (MDA), hydrogen peroxide (H2O2), DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity, and proline level were significantly increased while the chlorophyll content was decreased by drought stress in A. hirta leaves. The highest proline content and DPPH scavenging activity were shown in Ecotype of Youngduk with least MDA and H2O2 levels while the highest MDA and H2O2 contents, and least proline and DPPH levels were shown in Gunsan, respectvely. These results indicate that the Youngduk is the most tolerant and Gunsan is the most sensitive ecotype among the five different collections. Together, these results provide a new insight of overall physiological responses of A. hirta to drought stress.

ABSTRACT
 Ⅰ. INTRODUCTION
 Ⅱ. MATERIALS AND METHODS
  1. Collection of Arundinella hirta ecotypes, growing anddrought treatment
  2. Estimation of chlorophyll content
  3. Estimation of malondialdehyde (MDA) content
  4. Determination of H2O2 content
  5. Free proline content determination
  6. DPPH-radical scavenging activity determination
  7. Statistical Analysis
 Ⅲ. RESULTS AND DISCUSSION
  1. Effect of drought on chlorophyll content
  2. Changes in DPPH-scavenging activity and free prolineaccumulation
  3. Changes of malondialdehyde (MDA) and H2O2 content
 Ⅳ. CONCLUSION
 Ⅴ. ACKNOWLEDGEMENT
 Ⅵ. REFERENCES

• Byung-Hyun Lee(Division of Applied Life Sciences (BK21Plus), IALS, PMBBRC, Gyeongsang National University) Corresponding author
• Chang-Woo Min(Division of Applied Life Sciences (BK21Plus), IALS, PMBBRC, Gyeongsang National University)
• Inam Khan(Division of Applied Life Sciences (BK21Plus), IALS, PMBBRC, Gyeongsang National University)