Physiological and Molecular Characterization of the Differential Response of Broccoli (<i>Brassica oleracea</i> var. <i>Italica</i>) Cultivars Reveals Limiting Factors for Broccoli Tolerance to Drought Stress
Sergio Chevilly, Laura Dolz‐Edo, Manuel López-Nicolás, Luna Morcillo, Alberto Vilagrosa, Lynne Yenush, José Mulet
Abstract
Plenck) cultivars, previously characterized as drought-sensitive or drought-tolerant. This approach aims to identify different traits, which can constitute limiting factors for drought stress tolerance in broccoli. For this purpose, we have compared several physiological parameters and the complete profiles of amino acids, primary metabolites, hormones, and ions of drought-tolerant and drought-sensitive cultivars under stress and control conditions. We have found that drought-tolerant cultivars presented higher levels of methionine and abscisic acid and lower amounts of urea, quinic acid, and the gluconic acid lactone. Interestingly, we have also found that a drought treatment increases the levels of most essential amino acids in leaves and in florets. Our results have established physiological and molecular traits useful as distinctive markers to predict drought tolerance in broccoli or which could be reliably used for breeding new cultivars adapted to water scarcity. We have also found that a drought treatment increases the content of essential amino acids in broccoli.