Flowers and berries DefH9-iaaM gene expression and effects on IAA content, yield and quality of transgenic table grape, 'Thompson seedless' and 'Silcora'.

摘要

Field trials already confirmed the agronomical advantages of the DefH9-iaaM engineered eggplant, table tomato, strawberry, and raspberry with respect to their controls. Objective of this work is the first characterization of two table grape cultivars (‘Silcora’ and ‘Thompson Seedless’) genetically modified with the auxin synthesising gene DefH9-iaaM cultivated in open field conditions. The DefH9-iaaM transgenic clones were grown in open field standard cultivation conditions and compared with the corresponding controls. From plantation, at each cultivation cycle, GM and control plants were evaluated for their agronomic performance and quality fruit production. Data reported in this work are referred to the production cycles after three and four years from plantation, corresponding to the second more stable production year. Real time quantitative PCR revealed a different expression level of the DefH9-iaaM gene among the different stages of flowering and berry set and development. Total auxin (IAA) content of young flower buds and berries at fruit set (analysed by GC-MS) was higher in GM lines then controls. These observations suggest the importance of DefH9-iaaM gene for increasing grape productivity and also the substantial equivalence of berry quality nutritional attributes.