FEATURE
GENOMICSENABLED BREEDING FOR TURFGRASS By Hongxu Dong Turfgrass breeders seek to improve grasses for a variety of end uses. The ultimate goal is a variety capable of withstanding challenging environments without unnecessary inputs and pampering, all while providing an aesthetically pleasing appearance. Through plant genomics, we can sequence the genes and then study the relationships of those genes on typical characteristics. Plant genomics aims to characterize the genetic compositions, variations, structures, functions, and networks in plant genomes. Through it, we will gain better understanding of genetic mechanisms of traits of interest in order to produce better turfgrass varieties.
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superior grass growing on the plains of Africa may have value only to the cattle (Bos taurus) or wild herbivores that graze it. Although it has intrinsic value, its economic value is limited. If this plant is collected, evaluated, used in a breeding program, production tested, and released as cultivar that is planted on a large acreage, its value is greatly improved. This is the basic procedure of bermudagrass cultivar development. Bermudagrass is now the dominant warm-season turfgrass species in the southern US and has contributed billions of dollars to the economy. Bermudagrass (Cynodon spp.) is a warm-season, fine-textured turfgrass adapted to a wide range of environmental conditions. It is a drought-tolerant, durable, and versatile turfgrass that can be used in many settings, including golf courses, athletic fields, home lawns, and as utility turfgrass. Common bermudagrass (C. dactylon) and African bermudagrass (C. transvaalensis) are the two primary species used in breeding improved bermudagrass. Bermudagrass species are largely self-incompatible, meaning that they rely upon cross-pollination rather than self-pollination. African bermudagrass is a diploid, meaning it has two copies of chromosomes. It readily crosses with tetraploid (having four copies) and hexaploid (having six copies) common bermudagrass. Hybrid bermudagrass (C. dactylon × C. transvaalensis) has been successfully employed in the development of turf cultivars, in fact most commercial turf-type bermudagrasses are crosses of African bermudagrass and common bermudagrass parent plants. Interspecific hybrids such as ‘Tifgreen 328’ and ‘Tifway 419’ are well known standards for golf courses in warm subtropical and tropical climates.
28 • MISSISSIPPI TURFGRASS • SPRING 2022
PHOTO 1: Greenhouse grown pots of more than 130 populations that are now transplanted in field conditions.
PHOTO 2: Dr. Hongxu Dong, Mississippi State University Turfgrass Breeder.
