Principles of Plant Genetics and Breeding. George Acquaah

for their own use. This could be particularly advantageous to poorer farmers in developing countries. In addition, farmers who live in remote regions where government or commercial seed suppliers are not available could essentially guarantee themselves a yearly supply of quality hybrid seed. These farmers would not be dependent on government or commercial seed suppliers once a suitable cultivar was introduced into their area and could provide farmers greater control regarding the production and use of their locally generated product. However, farmers utilizing such “on the farm seed production rational” need to be aware of seed quality issues as well as the enforceable and legal ramifications of selling and or distributing such seed protected by licence, patent, or PVP. Growers should also be aware that the lack of genetic diversity or uniformity that is embedded in their apomictic seed crop could eventually make that variety susceptible to a particular disease infestation. Retaining and sowing an apomictic seed crop over the long term could eventually result in major disease infestations and a dramatic reduction in crop yield.

      At this time, it is difficult to visualize how the application of cytogenetics, molecular genetics, mapping, and genetic engineering, coupled with traditional breeding procedures, will be readily integrated to incorporate apomixis into maize and develop a apomictic hybrid corn cultivar anytime in the near future. Some have given the development of apomictic hybrid corn an approximate twenty‐year horizon; others much longer. As has been discussed above, the research process to be utilized to develop apomictic corn, or other species is time consuming, difficult and generates several legal, social, breeding and genetic issues that will need to be resolved. Though the transfer of apomixis holds much promise, it will be some time before a commercial apomictic maize hybrid will reach the marketplace.

References

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      6.11.1 Objectives of wide crosses

      Wide crosses may be undertaken for practical and economic reasons, research purposes, or to satisfy curiosity. Specific reasons for wide crosses include the following:

       Economic crop improvementThe primary purpose of wide crosses is to improve a species for economic production by transferring one or a few genes, or segment of chromosomes or whole chromosomes from a donor across interspecific