Molecular characterization and biotechnological improvement of the processing quality of potatoes

Abstract

Li, X.-Q. 2008. Molecular characterization and biotechnological improvement of the processing quality of potatoes. Can. J. Plant Sci. 88: 639Á648. Fries, chips, starches, flakes, and frozen pre-cooked potatoes, such as hash browns, are currently the main products made from processed potatoes. The processing quality of potatoes is largely determined by the carbohydrates, such as starch and glucose, in their tubers. The quantitative inheritance, heritability variation, transgene pleiotropic effects, and storage condition requirement of the processing quality are partly due to the carbohydrate metabolic network plasticity in potatoes. Pathway partition of sugars influences the processing quality such as chip color. This presentation attempts to review traditionally separate but related aspects (i.e., genetics, breeding, genomics, metabolism, marker-assisted selection, and transgenic engineering) of the potato processing quality and to discuss the integrated approach to its genetic improvement.Key words: Solanum tuberosum L., French fries, chips, carbohydrate metabolism, dry matter content, cold sweetening tuber morphology, metabolic network, partition of sugars, gene expression profile, transgenic regulation Li, X.-Q. 2008. Caracte´risation mole´culaire et ame´lioration biotechnologique de la qualite´de transformation des pommes de terre. Can. J. Plant Sci. 88: 639Á648. Parmi les principaux produits de la transformation des pommes de terre, on trouve les frites, les croustilles, l'amidon, les flocons et les pommes de terre pre´cuites et congele´es telles les pommes de terre rissole´es. La qualite´de transformation de´pend dans une large mesure de la composition d'hydrates de carbone comme l'amidon et le glucose dans le tubercule. L'he´re´dite´quantitative, la variation de l'he´re´dite´, les effets ple´iotropiques des transge`nes et les conditions d'entreposage associe´es a`la qualite´du produit transforme´re´sultent en partie de la plasticite´du re´seau me´tabolique des glucides chez la pomme de terre. La division du voies du me´tabolisme des sucres influe sur les parame`tres de la qualite´de transformation comme la couleur des croustilles. L'auteur passe en revue des aspects souvent juge´s distincts mais pourtant apparente´s de la qualite´de transformation des pommes de terre (a`savoir ge´ne´tique, ame´lioration, ge´nomique, me´tabolisme, se´lection au moyen de marqueurs et manipulation ge´ne´tique) et parle d'une approche inte´gre´e al 'ame´lioration ge´ne´tique de cette culture.

Systematic analysis of potato acid invertase genes reveals that a cold-responsive member, StvacINV1, regulates cold-induced sweetening of tubers

“…This is detrimental to the quality of processed potato products because of the Maillard reaction that occurs between the reducing sugars and amino groups under high cooking temperatures (Smith 1987). Molecular physiological approaches have facilitated signiWcant advances in our understanding of the processes that regulate sucrose-starch interconversion in the potato tuber (Li 2008). The problem of cold-induced sugar accumulation is inXuenced by starch biosynthesis and degradation, glycolysis, and mitochondrial respiration, as well as by hexogenesis (Sowokinos 2001).…”

StInvInh2 as an inhibitor of StvacINV1 regulates the cold‐induced sweetening of potato tubers by specifically capping vacuolar invertase activity

“…During low‐temperature storage, starch breaks down and sucrose is formed via UDP‐glucose pyrophosphorylase and sucrose‐phosphate synthase; the sucrose is subsequently hydrolysed by soluble acid invertases, yielding the RS (glucose and fructose) (Li, ; Sowokinos, ). The extent of the RS accumulation is genotype dependent.…”