Two hundred and ninety‐nine accessions representing 11 cultivar groups of Brassica oleracea and eight additional accessions of the wild species B. cretica, B. incana, B. insularis and B. villosa were screened for resistance to Verticillium wilt. A disease index (DI) was calculated for each accession, and a correction of the DI was carried out to compensate for a fluctuating infection level between 11 independent trials. A total of 235, or 77% of the accessions tested, had a DIcorr less or equal to the oilseed rape cv. ‘Express’ (DIcorr= 2.81), the reference cultivar. Only one accession of the wild species, B. incana, showed an enhanced level of resistance (DIcorr= 2.01). Twenty‐four accessions, distributed over eight cultivar groups of B. oleracea were selected for subsequent crosses involving B. rapa. Hybrid plants with 14 accessions were resultant and seed was obtained from crosses where the cultivar groups acephala, alboglabra, botrytis, capitata, gemmifera, italica and sabellica were used as female parents. When progeny of the produced resynthesized rapeseed lines were evaluated for Verticillium wilt resistance, three lines showed a significantly lower disease index (P ≥ 0.01) compared with the cv. ‘Express’. This source of resistance is now being crossed to advanced breeding material of oilseed rape.

A total of 257 parental wheat and 38 triticale lines were used for anther culture. On average, 2.1 green wheat haploids were obtained per spike. This response occurred irrespective of the origin of the material (Germany, France, Sweden or UK) and 5 years of testing. Triticale responded with 5.3 green haploids per spike. Using the criterion that one parental line should give at least one green haploid per spike in the screening experiment, green haploids were produced from 88 out of 91 F1 wheat breeding combinations and from each of 21 F1 and F2 triticale breeding combinations. An average of 4.7 green plants were obtained per spike from the wheat production programme, while the triticale programme gave an average of 6.2 green plants per spike. A single medium supplemented with different hormones for anthers and embryos was used for culture of both crops.

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The winter wheat varieties 'Starke' and 'Cappelle Desprez' and the spring wheat 'Chinese Spring' were analysed for structural chromosome rearrangements that resulted in the formation of multivalents in F1 hybrids. The analyses were carried out using hybrids involving euploids, monosomic and ditelosomic stocks, and double-monotelodisomic constructs. The study confirmed that 'Cappelle Desprez' differs from 'Chinese Spring' in a reciprocal translocation between chromosomes 5B and 7B (Riley et al. 1967); a translocation involving chromosomes 3B and 3D could not be verified. Furthermore, the analysis showed that 'Starke' differs from 'Chinese Spring' in a reciprocal translocation between chromosomes 7A and 7D. Both translocations have a coefficient of multivalent realisation of about 0.84. Further multivalents in euploid 'Starke', in euploid and some aneuploid stocks of 'Cappelle Desprez', and in euploid as well as various types of aneuploid hybrids between all three varieties could nearly all be explained hypothesizing that chromosome 2B of both 'Starke' and 'Cappelle Desprez' is a duplication-deficiency chromosome. In the hypothesis a part of the long arm of 2B is missing and replaced by a duplicated part of the long arm of chromosome 2D. The multivalents of this rearrangement showed an average coefficient of realisation of about 0.09.