Synthesis and cytogenetic characterization of intergeneric hybrids of Diplotaxis siifolia with Brassica rapa and B-juncea

Intergeneric hybrids involving a wild crucifer, Diplotaxis siifolia (2n = 20; (DDs)-D-s), and two crop Brassica species, namely Brassica rapa (2n = 20; AA) and B. juncea (2n = 36; AABB), were developed through sequential ovary/ovule culture. Hybridization was successful only when D. siifolia was used as the female parent, indicating unilateral cross incompatibility. Hybrids were intermediate between the parents for morphological characteristics but had low male as well as female fertility. Meiotic studies of hybrids revealed partial homoeology between D-s and A/B genomes.