Relative response of several varieties of potatoes to progressively changing temperatures and photoperiods controlled to simulate “northern” and “southern” conditions

Summary

For the purpose of determining adaptability and nature of response of varieties when grown in widely differing latitudes, two strains of Triumph potatoes and five other varieties were grown in the greenhouse under day length and temperature conditions simulating those that occur in the gulf coast (“southern”) and those occurring in northwestern Nebraska (“northern”). Potatoes were harvested at intervals to determine the morphological development throughout the life period.

With all potato varieties tested under “northern conditions” in contrast with “southern conditions” maximum vegetative growth was greater and continued later into the season, stolon growth was much more extensive, tubers developed later and in greater numbers with greater total weight, but ratios of weight of tubers to that of the tops were lower.

The early varieties were able to develop larger vines and more tuber weight early in the season under northern conditions while days were still hot and long than could the late varieties which responded better to the cool short days late in the season.

The “northern” type of environment permits the manifestation of more varietal differences than does the “southern” type.

When judging tuberization efficiency by ratios of green weights of tubers to tops, the early varieties appeared more efficient than the late ones under both conditions.

Stolon growth and numbers of tubers set were increased to a very much greater extent under northern than under southern conditions with the Triumph than with any other variety.