Use of fusicoccin in the early selection of durum wheat for tolerance to water stress

Abstract

The use of the fungal metabolite fusicoccin (FC) to induce water stress in durum wheat for the early selection of drought-tolerant genotypes of durum wheat was investigated. The experiments were carried out in a plant-growth chamber using seedlings of two cultivars: Creso and Simeto. Several concentrations of FC (from 10-7 to 10-5 M) and different modes of application were compared. Changes in the water status of seedlings during the experiments were assessed by measuring variations in fresh weight, leaf water potential, relative water content and transpiration. The results indicated that, under the environmental conditions adopted (20°C, 65% RH, 80 µE m-2 s-1 continuous illumination), the best simulation of water stress was obtained using cuttings of durum wheat seedlings treated with 10-5 M FC solution (6.8 µg ml-1) for at least 24 hours. ‘Simeto’ tolerated FC-induced water stress better than ‘Creso’. This result agrees with previous data from both indoor and outdoor experiments in which other water stress agents were used.