Submitted to: Book Chapter
Publication Type: Book / chapter
Publication Acceptance Date: 10/3/2004
Publication Date: 12/15/2005
Citation: Lapitan, N., Jauhar, P.P. 2005. Molecular markers, genomics and genetic engineering in wheat. Genetic Resources, Chromosome Engineering, and Crop Improvement 2:99-114, CRC Press, Boca Raton, FL. Interpretive Summary: Bread wheat is the most important cereal used for human consumption worldwide. Durum wheat or macaroni wheat is also widely used for preparing pasta and semolina. Genetic improvement of wheat has generally been accomplished by conventional breeding, sometimes in conjunction with hybridization with its perennial or annual relatives. This process has been very slow. Recent tools of molecular genetics and biotechnology offer prospects for considerably increasing the efficiency of wheat breeding. This article summarizes these tools that can provide insights into the genetic control of important traits, markers for gene manipulation, and techniques of introducing novel sources of genetic variation into wheat. These supplementary tools could speed up breeding programs. Thus, the use of transgenic approaches to combat pests and diseases, improve tolerance to abiotic stresses, and to upgrade grain quality of wheat is opening up exciting possibilities for accelerating wheat breeding programs. Hopefully, the enormous potential of the new technologies will be harnessed to the best advantage of humankind.
Technical Abstract: Bread wheat, Triticum aestivum L. (2n = 6x = 42; AABBDD genomes), is the most widely grown cereal crop and is the staple food for 15% of the world's population. Durum wheat or macaroni wheat (Triticum turgidum, 2n = 4x = 28; AABB genomes) is also an important cereal used for human consumption worldwide. Its high protein content and gluten strength make it the choice wheat for preparing pasta products. Increasing costs of input, such as fertilizer, water, and fuel, will lead to reductions in their use. Therefore, maximizing the use of genetic variation to improve wheat will continue to be a challenge for wheat breeders. Conventional breeding sometimes combined with wide hybridization with perennial grasses of the tribe Triticeae, has contributed to the genetic improvement of bread wheat, although it has been a slow process. Tools of molecular genetics and biotechnology offer possibilities for significantly increasing the efficiency of wheat breeding. These tools can provide insights into the genetic control of key traits, markers for manipulation, and methods for introducing novel sources of genetic variation, thereby speeding up the breeding process. This review presents a summary of three areas of research that offer great potential in wheat improvement. These include: 1) application of molecular makers in wheat breeding; 2) development of genomics tools; and 3) wheat transformation. It is concluded that these molecular and transgenic technologies hold great potential for the genetic enrichment of wheat.