Genetics and plant breeding

Gene mutations provide the primary means of understanding gene structure and function in plants. A large number of mutants have been identified that affect a wide range of anatomical traits, ranging from embryogenesis to the adult plant. Numerous mutants have been isolated that directly control the root and shoot development, meristem behavior, epidermal cell formation, root hair and trichome development, and vascular tissue differentiation. Hybridization occurs when two different, naturally occurring plant populations show a breakdown in reproductive isolation and an exchange of genes between diverse individuals takes place. In several cases, the hybrids are more or less intermediate in quantitative features. The Aloineae are a well-defined tribe of the monocotyledonous family Liliaceae that provides an insight into the inheritance of leaf anatomical characters. Wood quality is determined by the combined effects of several interrelated and variable wood properties. Heritable wood properties include the amount of juvenile and mature wood, grain pattern, individual cell size and wall characteristics, and chemical properties of the cell wall. Some wood properties can be manipulated during processing, but others are stable features that can only be altered by a focused tree-breeding program.