Relations between biomass maintenance of potato clones and the growth and yield of their progeny seedlings at low temperatures

Summary The main purpose of the research reported in this article was to see if the biomass maintenance of parental potato clones was correlated with the growth and yield of their progeny. Seedling populations with parents of European and of Andean origin were cultivated at a temperature of 10°C during the day and 4°C at night. The biomass maintenance of the parents was defined as the ratio between the total biomass yield at 20°C day/10°C night and the total biomass yield at 10° C day/4°C night. The Andean parents had good maintenance ability at the lower regime compared to the Eurpean parents.Biomass maintenance appears to be hereditary. Significant correlation was found between the dry matter maintenance of the parents and the growth rate of seedlings, especially during the second month after potting. In populations with only Andean or only European parents, differences in height increase and leaf formation rate between seedling populations were correlated to the dry matter maintenance of the parents cultivated at the temperature regime 10/4°C. In the hybrid population between an Andean and an European parent only differences in height increase during the second month after potting correlated well to the average dry matter maintenance of the parents. It appears therefore that the rate of height increase during the second month after potting can be used as a criterion for selection.