Frequency of 2 n pollen in diploid hybrids between Solanum phureja Juz. & Buk. and Solanum chacoense Bitt.

Solanum phureja (PP)x Solanum chacoense (CC) hybrid families (PC) were evaluated for pollen fertility and frequency of 2 n pollen in two seasons in Morocco. PP clones produced high frequencies of 2 n pollen, whereas CC clones produced none. The percentage of plants with 2 n pollen ranged from 2 to 63% among 20 PC families and was consistent in some PC families over two growing seasons, whereas others varied between fall and spring growing seasons. The expected ratio of 2 n to non-2 n pollen-producers within a PC family based on a single recessive gene model [i.e. 1:0 with CC homozygous dominant (PsPs) or 1:1 with CC heterozygous (Psps)] was observed in only 5 of 20 progenies. Narrow sense heritability was 0.71, allowing gain from further selection. Only clones producing more than 10% 2 n pollen exhibited more stable expressivity across seasons. © 1992 Kluwer Academic Publishers.