Genetic variance of reducing sugars and dry matter and their correlations with agronomic traits in potatoes

The objective of this research was to estimate the components of the varian ce and heritability relating to reducing sugars content and to dry matter, and their correlations with some agronomic traits of potato (Solanum tubero sum L.). Forty potato clones randomly chosen by the Embrapa-Centro de Pesqu isa Agropecuaria de Clima Temperado Breeding Program were used. The field e xperiments were carried out in the fall and in the spring of 1996, in Pelot as, RS, Brazil. Sugar and dry matter content were analyzed after storing tu bers in cold chamber (5 +/- 1 degrees C). Genetic variances relating to red ucing sugars and to dry matter content were moderate, and error variances w ere high, providing relatively low heritability values for both traits. The reducing sugar content was positively and significantly correlated with mo st of the agronomic traits and negatively correlated with dry matter conten t. The correlations between dry matter and agronomic traits were low and no t significant.