Impiego delle biotecnologie per migliorare la qualità della lattuga

Genetic transformation of lettuce by A. tumefaciens has been standardised and manipulation of traits such as leaf shape and nitrogen metabolism has been carried out. Lettuce (cv Luxor) overexpressing the homeobox knotted-like gene KNAT1 of A. thaliana under the pea plastocyanin promoter featured leaves with increased vascular net, lobes at margins and higher content of cytokinin hormones, which delayed senescence, as compared to wild types. Lettuce overexpressing the asparagine synthetase A from E. coli under a chimaeric promoter derived from 35S and mannopine synthase promoters exhibited accelerated growth, higher fresh and dry weight and reduced content of nitrates compared to untransformed plants. Finally, from open field trials, pollen transmission was estimated very poor (1%) even when donor and recipient plants were in close proximity