Fruit Trees Transformation: Methodology and Application

Artificial Climate Station Biotron, Branch of Institute of Bioorganic Chemistry RAS, 142290 Pushchino, Moscow Region, Russia. This e-mail address is being protected from spambots. You need JavaScript enabled to view it.

Key words: fruit trees transformation, herbicide resistance, taste improvement, virus resistance

Fruit crops are an especially suitable target for improvement through direct gene manipulations because of the genetic limitations associated with high heterozygosity and polyploidy which hamper the conventional breeding programs. The development of reliable regeneration systems from somatic tissues is a prerequisite for the application of gene transfer techniques to improvement of woody species. High regeneration frequencies of commercial apple, pear, plum and sour cherry cultivars as well as pear and apple dwarf clonal rootstock have been achieved in our laboratory. Efficient transformation methods for these cultivars were also developed by usage different transformation protocols and selective agents. Positive selection based on phosphomannoseisomerase genes (pNOV35S-GFP, Syngenta) was used for production of marker free transgenic plum trees, that very important for improve its attractively for consumers. Herbicide resistant fruit rootstock is a new way conferring selectivity and enhancing fruit crop safety and production. The bar gene have been used in our research for obtaining phosphinotricine-resistant apple and pear clonal rootstocks. For fruit taste improvement of important temperate horticultural crops apple and pear, the gene of supersweet protein thaumatin II from Th. danielli has been transferred to apple and pear cultivars by usage agrobacterial strain CBE21 and vector pBI121thau based on the coding sequence cloned in Unilever. For improving resistance for one of the most serious disease of stone fruits - sharka or plum pox, vector constructs based on coat protein gene in sense, antisense orientation and RNAi phenomena generation were created. Transgenic plum plants expressed coat protein was obtained on hygromycin based selection. Since 2000 year most of resulted transgenic plants are testing in field conditions.