Variability of flowering and 2n pollen production in diploid potatoes under high temperatures

Abstract

Nine clones from a heat tolerant PHU-STN hybrid population were evaluated for flower production and percent normal, 2n and non-viable pollen under three temperature regimes at the Southeastern Plant Environmental Laboratories: 30/26, 26/22 and 22/18 C. No flowering was observed at 30/26 C. Flowering was irregular among seven of the clones at 26/22 C and 22/18 C. One clone produced numerous flowers at 26/22 C and 22/18 C. The plot of percent 2n pollen against time for this one clone under 22/18 C revealed a slope which was statistically different from zero but too small to be of practical value. The same plot of this clone under 26/22 C revealed a slope which was not statistically different from zero. Percent 2n pollen was statistically greater (at the 10% level of significance) in the 26/22 C chamber than the 22/18 C chamber.