A Preliminary Study On The Cold Resistance Of Spermidine Synthase Gene (SPDS) Transgenic Potato Plants

The improving resistance of potato varieties to environmental stresses is one of the main goals of potato breeding. Polyamines are closely related with plant resistance to abiotic stresses, and the spermidine synthase is the key enayme of polyamine biosynthesis. Our study takes spermidine synthase gene (SPDS) transgenic potato plantas material. Firstly, we confirm the successful expression of SPDS gene in transgenic potato, and then evaulate SPDS transgenic potatoes cold resistance with chilling stress treatment by assaying relativeconductance, polyamine contents and physiological and biochemical index, finally make a preliminary analysis on high-throughput transcriptome sequencingresult. The main results are as follows:1 By PCR, RT-PCR and polyamine HPLC quantitative analysis, we screen out optimal six lines of SPDS transgenic potatoes with stable SPDS expression and strengthen polyamine content among total 14 candidate transgenic potatoes.2 By observing and assaying clod stress response, fertility status andartificial freezing cold processing leaf relative conductivity under cold temperature treatment, we find the above six lines of SPDS transgenic potatoes have a more excellent response than controls, which indicates SPDS transgenic potatoes take a stronger ability of cold resistance.3 By further assayingpolyamine content, photosynthesis and several physical resistance indexes, we also find SPDS transgenic potatoes have a more excellent response than controls,which may hints us a primary mechanism on how SPDS transgenic potatoes get a improving cold tolerance.4 By means of digital gene expression profiling (DGE) technique, we sampling SPDS transgenic potatoes 02-42 and controls Dongnong 303 as materials under cold stress treatment respectively, and then make a basic differential genes expression analysis, based on the analysis we find there are 14 gene with significant difference on mRNA levels and 7 genes among them could contribute to improve cold resistance of SPDS transgenic potato plants.