Research on Two Main Economical Characters in Potato Using Molecular Approach.pdf

1、Potato is the third most important food crop in the world afier wheatand rice, which are grown in nearly 125 countries on more than 48million acres worldwide. Potato consumption has increased steadily indeveloping countr

2、ies, which now account for more than half of the globalharvest. Due to potato's ease of cultivation and its high energy content,potato has been a valuable cash crop for millions of farmers. Accumulation of reducing suga

3、rs during cold storage is a persistentand costly problem for the potato processing industry. High temperatureprocessing of potato tubers with elevated amounts of reducing sugarsresults in potato chips, fries and other pr

4、oducts that are unacceptable toconsumers because of their bitter taste and unappealing dark color. Moreproblematically, such products contain rncreased amounts of acrylamide,a neurotoxin and a potential carcinogen. Silen

5、cing of the potato vacuolaracid invertase gene VInv can prevent reducing sugar accumulation incold-stored tubers. Using this approach we developed Vlnv gene silencinglines using RNA interference (RNAi) from four potato c

6、ultivars growncurrently for potato chip production in North America. Accumulation ofreducing sugars during cold storage was reduced by ~93％ or more in allRNAi lines that had >90％ reduction of Vlnv transcript. Potato chip

7、sproduced from these lines were light colored and significantly lower inacrylamide than controls. Changes in growth and tuber yield were notassociated with Vlnv suppression using RNAi. We demonstrate thatsilencing of the

8、 VInv gene is an effective approach to control thecold-induced sweetening problem in potato. Potato late blight, caused by the oomycete pathogen Phytophthorainfestans, is considered as the No. 1 potato disease that is c

9、ostly to control.RB gene, cloned from the wild potato species Solanum bulbocastanum,confers broad-spectrum resistance to potato late blight. To betterunderstand the expression patterns and regulation of RB gene, the RBge

10、ne was transformed into potato cultivar Katahdin, drive by 35Spromoter. Among 11 transgenic potato lines used in this study, 5 linesshowed single genomic insertion of the RB gene, 4 lines showed 4 0r 5copies of RB gene,

11、and 2 lines contained more than 8 copies. It isconfirmed that the RB trangene driven by 35S promoter could conferresistance to late blight The results indicate that no significant correlationwas observed among RB transge

12、ne copy number and late blight resistancein 35S:RB lines. The results also showed a different pattem for RB geneexpression among 35S promoter-driven transgenic lines compared totransgenic RB lines driven by native promot