Band gapIn solid-state physics and solid-state chemistry, a band gap, also called a bandgap or energy gap, is an energy range in a solid where no electronic states exist. In graphs of the electronic band structure of solids, the band gap refers to the energy difference (often expressed in electronvolts) between the top of the valence band and the bottom of the conduction band in insulators and semiconductors. It is the energy required to promote an electron from the valence band to the conduction band.
LightLight or visible light is electromagnetic radiation that can be perceived by the human eye. Visible light is usually defined as having wavelengths in the range of 400–700 nanometres (nm), corresponding to frequencies of 750–420 terahertz, between the infrared (with longer wavelengths) and the ultraviolet (with shorter wavelengths). In physics, the term "light" may refer more broadly to electromagnetic radiation of any wavelength, whether visible or not. In this sense, gamma rays, X-rays, microwaves and radio waves are also light.
GraftingGrafting or graftage is a horticultural technique whereby tissues of plants are joined so as to continue their growth together. The upper part of the combined plant is called the scion (ˈsaɪən) while the lower part is called the rootstock. The success of this joining requires that the vascular tissues grow together. The natural equivalent of this process is inosculation. The technique is most commonly used in asexual propagation of commercially grown plants for the horticultural and agricultural trades.
Fabian strategyThe Fabian strategy is a military strategy where pitched battles and frontal assaults are avoided in favor of wearing down an opponent through a war of attrition and indirection. While avoiding decisive battles, the side employing this strategy harasses its enemy through skirmishes to cause attrition, disrupt supply and affect morale. Employment of this strategy implies that the side adopting this strategy believes time is on its side, usually because the side employing the strategy is fighting in, or close to, their homeland and the enemy is far from home and by necessity has long and costly supply lines.
RootstockA rootstock is part of a plant, often an underground part, from which new above-ground growth can be produced. It could also be described as a stem with a well developed root system, to which a bud from another plant is grafted. It can refer to a rhizome or underground stem. In grafting, it refers to a plant, sometimes just a stump, which already has an established, healthy root system, onto which a cutting or a bud from another plant is grafted.
Fruit tree propagationFruit tree propagation is usually carried out vegetatively (non-sexually) by grafting or budding a desired variety onto a suitable rootstock. Perennial plants can be propagated either by sexual or vegetative means. Sexual reproduction begins when a male germ cell (pollen) from one flower fertilises a female germ cell (ovule, incipient seed) of the same species, initiating the development of a fruit containing seeds. Each seed, when germinated, can grow to become a new specimen tree.
