The effect of aneuploidy upon the progeny of an autotetraploid Ribes nigrum

Authors

• Antero Vaarama State Horticultural Institute, Piikkiö, Finland

DOI: https://doi.org/10.23986/afsci.71349

Abstract

Morphological and developmental characteristics of a total of 139 even tetraploid (2n = 32), hypo- (2n = 31), and hypertetraploid (2n = 33, 34) Ribes nigrum plants derived from colchicine-induced autotetraploid parents have been under observation from the seedling stage to full maturity. The records made have been treated statistically by comparing different chromosome classes with each other, the purpose being to reveal the possible phenotypic effects of aneuploidy upon the species. It was found that a stringent elimination of hypotetraploid zygotes took place when the progeny studied developed. The effect of aneuploidy was to be seen only in some developmental characteristics in hypertetraploid chromosome classes. The effect was very slight in the 4 x + 1 types but more pronounced in the 4 x + 2 group. The effect was observed as a tendency to a lower growth rate during the active growth period of the plants. Furthermore, a tendency to a retardation of the beginning of flowering was observed, as well as an increased proportion of exceptional, long and short, growth periods in hypertetraploid populations. The vigour of monoploid 4 x + 1 types was fully maintained, and even an increase in growth rate as compared with that of even tetraploids was observed.