Schriften zu Genetischen Ressourcen - Genres

W. LÜHS et al.
as flea beetles (Psylliodes chrysocephela, Phyllotreta spp.), stem weevils (Ceutorhynchus
spp.) and field slugs (Deroceras spp.).
Introduction
Brassica crop species have become one of the most important sources of oil, condiments,
vegetables, forage and green manure world-wide (cf. DIEDERICHSEN 2001).
The co-operative project “Brassica collections for broadening agricultural use, including
characterising and utilising genetic variation in Brassica carinata for its exploitation
as an oilseed crop” (RESGEN CT99 109-112) has been initiated in order to
increase knowledge about the genetic resources available within the four important
Brassica species B. oleracea, B. rapa, B. napus and B. carinata, and to improve the
utilisation of their genepools in Europe by plant breeders and growers. To achieve
this, core collections are being established for each of the four species, with the intention
of providing coverage of the maximum possible variation available within existing
material in a representative set of well-characterised genotypes. In addition to
seed regeneration and characterisation of the material, extensive evaluation of the
four core sets with respect to important agronomic and phytopathological traits is
being carried out, with results to be made freely available via the European database
Bras-EDB (cf. BOUKEMA and VAN HINTUM 1999, LÜHS et al. 2002).
Gross evaluation of B. napus accessions
With the objective of creating such a B. napus core collection from all accessions
documented in Bras-EDB, a maximum quantity of information about the growth habit,
use and seed quality of the material integrated in the database has to be collected.
Differentiation between spring and winter B. napus types: For a basic differentiation
of the B. napus accessions (excluding ssp. rapifera), the characters winter hardiness,
vernalisation requirement, seasonality and type of use were used (Tab. 1). Following
this gross grouping of the material, 338 summer type B. napus accessions - including
oilseed rape varieties, fodder and green manure forms as well as „exotic“ types, incl.
vegetables (ssp. pabularia), Hakuran, Couve Nabica - were grown at the Field Research
Station in Rauischholzhausen (near Marburg/Hesse, Germany) in 2000. In
the vegetation period 2000/2001, a total of 857 B. napus winter type accessions were
sown for the same reason. In this trial genotypes were included that in the preceding
spring trial displayed a biannual growth habit (vernalisation requirement) and stayed
vegetative like forage types. Due to a relatively mild winter period in 2000/2001,
nearly all of these accessions survived and showed transition to the generative
stage. In addition to basic description of this large set of B. napus material (excluding
285