Periodic Reporting for period 1 - TESS (TARGETED ENGINEERING OF STONE FRUIT TREE GENOMES FOR RESISTANCE TO SHARKA)
Reporting period: 2018-05-01 to 2020-04-30
In WP1, we applied the CRISPR/Cas9 system to target Prunus susceptibility genes either to create a collection of de novo non-functional susceptibility genes (i.e. KO genes) or to target specific amino-acids relevant for compatible plant/virus interactions, without knocking-out the host genes. For this purpose, several sets of editing vectors have been produced and peach and plum cultivars have been transformed. Transgenic lines are currently under screening.
In WP2, we targeted the stone fruit tree flowering pathways through the expression or editing of florigens (TFL1, DOG1 etc…), both in peach and plum; or through the development of viral vectors can be used to transiently express flowering regulators in stone fruit seedlings.
1. Engineered forms of susceptibility host genes to PPV infection as breeding alternatives for viral disease resistance in stone fruit trees
2. Early flowering stone fruit genitors that display shorter juvenile phase thus allowing the implementation of rapid selection of mutants in those perennial species.
3. Fruit trees combining in the last phase of the project both constructs for non-functional susceptibility and early flowering genes to deliver PPV-resistant, transgene-free, plant material.