1. Future Trends
In view of the still long development period of 9 to 12 years it is
essential for the survival of the breeding enterprises to foresee what demands
growers, processors and consumers are likely to make on future varieties.
At present the following trends can be detected in wheat growing. In
the main they have economic reasons, ignore experience in plant growing and
make great demands on the varieties of the future in respect of stress tolerance
in general:
• The area used for wheat growing is increasing.
• Leaf crops, which are very good preceding crops for wheat, are
decreasing.
• This will result in a steadily rising percentage of stubble wheat or
even permanent wheat growing.
• The sowing time is being moved forward to September even in locations
with mild weather conditions.
• Care in tilling the soil in general, and the handling of stubble in
particular, is declining, and it is likely to decline even further as energy
costs rise.
A likely result of these "sins of crop rotation" is that
greater demands will be made on the health of the varieties. In particular,
progress in breeding will be needed in respect of the leaf diseases associated
with crop succession and also the entire foot-rot complex, especially Pseudocercosporella
herpotrichoides (stem break eye spot, strawbreaker) and Ophiobolus graminis
(blackleg disease, take-all).
As with barley, a shift of the sowing season into September permits
greater penetration of the soil by the roots during the autumn. In conjunction
with mild winters, this results in a high risk of infection with viruses
transmitted by soil fungi. And as with winter barley, we shall have to reckon
with a similar virus that is specific to wheat and already on the advance in
the countries on Germany's western borders.
2. New Breeding Technologies in
Central Europe
In addition to the conventional methods (Fig. 7), more and more
procedures based on biotechnology are becoming available to breeders for the
development of new varieties. It has to be decided from the point of view of speed,
reliability of selection and cost which method or combination of methods is the
most promising. With all diseases that are difficult to study and record with
sufficient accuracy, such as the foot-rot complex, and where there is a highly
polygenic basis for resistance, as with ear Fusarium, and also in the case of
diseases that do not normally occur in the nursery, it would seem helpful to develop
molecular markers which can then be used to carry out specific selection in
young generations.
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| Fig. 7: Castration of a wheat flower |
The use of molecular markers can also considerably shorten the
breeding procedure in back-crossing programmes with non-adapted genotypes, since
selection can be carried out for the genome of the parent as well as for the target
gene. However, a condition for this is reasonably close and evenly distributed
cover of the genome by these markers.
This has nothing to do with genetic engineering in the proper sense of
the term, since the latter has not yet passed the basic research stage in
cereal breeding. And this situation is unlikely to change as long as the
majority of consumers do not accept genetic modification and until optimized
and efficient constructs
are available for transformation. But in the long term genetic engineering
promises to bring considerable progress in breeding through the use of genetic
diversity in conjunction with the conventional methods.
From the point of view of breeding the quality characteristics have a
high level of hereditability, i.e. the genes of the variety have a very strong influence
on quality. For this reason there should be a long-term catalogue of breeding requirements,
integrated into the development of new varieties, for use as starch, brewing or
biscuit wheat on the lines of the successful selection for baking quality.
The growing of varieties tested in Germany for three years by the BSA,
the resulting precise and comprehensive description of quality and consideration
of these characteristics in the choice of varieties would prevent a great many
of the problems that made it difficult to market the crops of the last three years.
The value of a variety is determined by a number of important growing,
resistance and quality characteristics as well as by the yield. More than in
the past, perhaps, there is a need to make use of these in the varieties of
today and tomorrow in organic farming. Then a little less may be more in the
wheat harvest as in so many other fields.
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