EVALUATION OF PROLINE ANALYSIS AND CHLOROPHYLL FLUORESCENCE QUENCHINGMEASUREMENTS AS DROUGHT TOLERANCE INDICATORS IN DURUM-WHEAT (TRITICUM-TURGIDUM L VAR DURUM)

The possibility of using proline accumulation and fluorescence inhibit ion as predictive tests for drought tolerance in durum wheat has been investigated. The drought susceptibility of 25 genotypes was evaluated by comparing yields and yield components in irrigated and non irrigat ed conditions in the field. A drought susceptibility index (DSI) was c alculated based on yields from irrigated and dry treatments and compar ed with the results obtained using the two physiological criteria. Pro line accumulation and chlorophyll fluorescence inhibition were found t o be significantly and negatively correlated with DSI of grain yield, biological yield, and thousand kernel weight, and tiller index. The us e of both criteria for breeding durum wheat in Mediterranean dryland i s discussed.