Transgenic potato lines expressing CP4-EPSP synthase exhibit resistance against glyphosate

Abstract

Potato crops are particularly vulnerable to weed competition from emergence to canopy closure and are subject to significant yield loss. Glyphosate is broad spectrum herbicide used to control weeds worldwide. In order to incorporate glyphosate resistant trait in four potato cultivars (Lady Olympia, Desiree, Agria and Granola), an efficient, cost effective, reproducible and stable Agrobacterium-mediated genetic transformation protocol was performed using leaf and internodal explants. Agrobacterium strain LBA4404 harboring newly modified recombinant binary vector pCAMHE-EPSPS containing EPSP synthase gene under the control of Cauliflower mosaic virus 35S promoter was used to infect explants. The overall transformation efficiency was 26.4%. Of the 280 plants transferred to greenhouse, 74 plants were found to be PCR positive with gene of interest. GUS histochemical, Southern blot, RT-qPCR, lateral flow dipstick assays confirmed integration and expression of EPSPS in primary transformants. The putative transgenic plants developed from these cultivars possessed enhanced resistance to glyphosate applications in T0 and first tuber generation. These transgenic potato lines could be used as source of germplasm for an efficient potato breeding program. The article reports the development of potato transgenic lines with enhanced tolerance against glyphosate.