Jf. Herrick et al., BARRIERS PREVENTING HYBRIDIZATION OF LATHYRUS-ODORATUS WITH L-CHLORANTHUS AND LATHYRUS-CHRYSANTHUS, New Zealand journal of crop and horticultural science, 21(2), 1993, pp. 115-121
Interspecific hybridisation of the sweet pea, Lathyrus odoratus L., wi
th two yellow flowered relatives, Lathyrus chloranthus Boiss. and L. c
hrysanthus Boiss., was undertaken with the aim of transferring yellow
flower colour into the sweet pea. Initial reciprocal cross pollination
s of L odoratus 'Original', with the two species, produced no viable s
eed, suggesting the presence of interspecific hybridisation barriers.
Observation of events following further reciprocal cross pollinations
confirmed the presence of hybridisation barriers which prevented the f
ormation of hybrid embryos in all cross combinations except L chlorant
hus x L odoratus. Post-fertilisation hybridisation barriers subsequent
ly prevented die maturation of such hybrid embryos. Further crosses us
ing a range of sweet pea cultivars indicated varying degrees of impedi
ment to hybridisation depending on the cultivar used. Pre-fertilisatio
n hybridisation barriers which prevented the growth of foreign pollen
tubes to the bases of styles were observed in L odoratus x L chloranth
us crosses and reciprocal L odoratus x L chrysanthus crosses involving
long-styled L odoratus cultivars.