Three factors are beginning to have a strong impact on maize breeding and will become increasingly important in the future. First, cereal genomics is currently undergoing a revolution. After 2005, the completion of the rice genome sequence radically changed how scientists and breeders approach challenges in rice genetic improvement. Having a high-quality reference sequence of rice led to many genetic discoveries that should improve the efficiency of rice selection and breeding, and synteny between the rice and maize genomes provides new perspectives for maize, especially following the
recent publication of the B73 inbred maize sequence (Schnable et al., 2009) and new developments in bioinformatics. New gene shuttle research between maize, rice, and other cereals will soon be a routine activity. Future maize geneticists will have to become cereal geneticists. However, there are two remaining bottlenecks that still challenge scientists and breeders: (1) high-quality routine trait phenotyping to link sequences to phenotypes; and (2) new IT tools and specialists to process genetic data and transform them into formats suitable for breeders.
Second, changes in climatic variability will definitely affect China, and especially northern China, in the next century (Wu and Wang, 1999). The entire maize scientific community will have to deal with the consequences of water scarcity, higher, more variable temperatures, and changing biotic stresses.
Third, maize used for feed currently accounts for more than 65% of the total production; 40 to 45% of that amount is fed directly to livestock and poultry with tremendous amounts of waste. Given the rapidly increasing meat and milk consumption in China, increasing amounts of maize grain, cobs, and possibly stalks will be processed into more digestible formulated products. In addition, the processing industries will use increasing amounts of maize to produce starch, alcohol, sugar, maize oil, glutamate, xylitol, and other derived products.
While China is the second most important producer of this cereal globally (after the USA), its maize processing industry, although growing rapidly, still lags far behind those of North America and Europe.
There are many maize processing enterprises in China, but few are large-scale operations capable of competing at the international level. Hence, downsizing to a lower number of more efficient enterprises is likely. These will probably also encompass other emerging applications in medicine (mannitol), industry (biodegradable plastics), and energy production (alcohol).
Acknowledgments
The authors thank Dr. Jennifer Nelson and Mr. Mike Listman, CIMMYT, Mexico, as well as Dr. Thierry Risacher, CAAS-NWIC, for kindly reviewing the English version of the manuscript.
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