Rapid estimation of the amylose/amylopectin ratio in small amounts of tuber and leaf tissue of the potato
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Small amounts of potato tuber and leaf tissues are extracted in perchloric acid. After staining with I2-KI solution absorbancies at 618 and 550 nm are measured. The amylose/amylopectin ratio can be estimated from the ratio of the absorbancies by using a formula or a graph in which the specific absorptions of the two compounds are introduced. Weighing of samples is not required. The method can be used for the estimation of the starch composition of minitubers and is especially suitable for the detection of mutants with an altered starch composition.
Additional keywordsminitubers starch composition mutant detection
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