Biotechnology in Forage Grasses: Tissue Culture, Genetic Transformation, Genome Editing, and Risk Assesment

Forage grasses can be grouped into two large categories; warm- and cool- season grasses. Warm-season grasses produce most of their growth during the warmer periods of the growing season, while the opposite is true for cool-season species. These grasses are utilized in many different agricultural production systems with greatest value as feeds for livestock. They are also useful for preventing soil erosion and maintaining soil fertility. A species may be grown alone, or in mixtures with other grasses or legumes at high or low levels of soil fertility. They may be grazed, or made into hay or silage for conservation. Many important warm-season perennial grasses multiply either by vegetative propagation, or form their seeds by an asexual mode of reproduction called apomixes. Possibility of improving of these plants by conventional breeding method depends on availability of natural genetic variation and its manipulation through breeding and selection. However, there are naturally not many genetic variations in apomictic grasses to generate new genetic variation.