Abstract:Drought, salt and chilling effects on proline accumulation were studied in 3-leaf-stage seedlings of three rice (Oryza sativa L.) varieties: IAC (sensitive to drought and salt, and tolerant to low temperature), Dahuanggu (salt-resistant but sensitive to low temperature) and Guixi (drought-tolerant). Treatments were carried out at -0.6 MPa PEG (simulation) for drought, 0.15 mol/L NaC1 for salinity, and 6 ℃ for chilling stresses. Proline content in aboveground part of rice seedlings were tested. The results showed that proline accumulation in rice seedlings of various varieties was seen under all stresses，and the proline content increased with increasing time of stress．Sensitive variety accumulated more proline content than tolerant one. It seems，however, that proline accumulation can not be used as a screening index of resistance to stres ses in rice seedlings.
