Transformation of potato (Solanum tuberosum) cultivars for conferring resistance to potato tuber moth, Phthorrimaea operculella : A dissertation submitted in partial fulfilment of the requirements for a Post Graduate Diploma in Applied Science, Lincoln University

Abstract

Plant transformation is considered to be an alternative to conventional breeding methods for conferring pest resistance in potato. An Agrobacterium-mediated transformation protocol was evaluated with two commercial New Zealand varieties (Iwa and Red Rascal) and two advanced breeding lines (Vtn. 62.3.3. and V393) using a binary vector containing a cry 1Ac gene and a selectable marker gene conferring kanamycin resistance. Putatively transformed calli colonies were recovered in all the cultivars, with Vtn.62.33.3 (18%) and Iwa (15 %) producing the highest percentages of colonies in relation to the number of explants. However, regeneration from cell colonies was not accomplished. Three different assays for characterisation of transgenic plants were tested on two Iwa lines previously transformed with cry genes (32 and 52). These lines were found to have resistance to kanamycin in a root initiation assay, to contain the cry gene using PCR analysis, and to have improved resistance to larvae of potato tuber moth.