SEPALOIDY IN THE RED RASPBERRY,RUBUS IDAEUSL

Abstract

Sepaloidy in the red raspberry, R. idaeus, is described and illustrated. The expression of the sepaloid character was shown to be affected by the environment and also, probably, by genetic modifiers. Criteria for distinguishing with certainty between normal and sepaloid plants in segregating families were established, and data obtained confirming the control of sepaloidy by a recessive gene, sx3. Sx3 is shown to be linked with the fruit color gene T with a crossover value of 17.0%, and with the gene B, controlling waxy bloom on the cane, with a crossover value of 11%. This study thus adds a 6th gene to the main linkage group so far established in R. idaeus.