Plant biotechnology (micropropagation, secondary metabolites, etc.) is the science of growing different plant cells under controlled artificial environment conditions. Thence, successful plant biotechnology depends on the techniques of plant tissue culture. Plant tissue culture laboratories have style needs that distinguish them from alternative forms of laboratories and a few wants are distinctive for successfully plant growth as well as production of plant secondary metabolites. The most often manipulated physical parameters are light, temperature, and relative humidity within the culture vessels. The light is most important physical factor which might have an effect on metabolite production. Light not only affects the in vitro growth and developments but also very important factor affecting the production of plant secondary metabolites. The action of light on plants happens in the most part in two ways. In the first way, the light source gives the energy required by the plant for photosynthesis. In the second way, the signal which gotten by photoreceptors it regulates plant metabolism, differentiation, and growth. Temperature is different with the different in vitro life cycle, as well as the aim of production such as plant growth or secondary metabolites production.
TopIntroduction
Plant biotechnology is presently utilized in several fields to attain completely different objectives like: micropropagation, in vitro preservation and cryopreservation, secondary metabolites' production etc. (Kozai and Smith, 1995).
The major factors of plant tissue culture, which are interconnected or linked to each other (Figure 1), are a) establishment and sterilized plant material, b) media composition for culture, and c) in vitro physical conditions for the growth room and the culture vessel (DeFossard, 1986).
Figure 1. The main barriers of plant tissue culture
The importance of in vitro culture futures, as contrasted to any other plant production system, is the exacting controlled, artificial, of the environment condition surrounded the in vitro cultures. All These environmental factors had a significantly affected on the growth characteristics (Lumsden et al. 1994; Chen, 2015). Unlike plants in the field, which is growing at the unpredictable environment changes, each factor of the tissue culture condition, surrounding the plant cell cultures within a vessel, can be managed (Kozai and Smith, 1995; Isah, 2015) (Figure 2).
Figure 2. An overview of plant tissue culture growth room A) empty growth room, and B) culture incubated in growth room
Physical condition, factors including temperature, light (quality, quantity and duration), air movement, and the culture vessels are predetermined and can be maintained as a constant or changing during the growth cycle of plant cell cultures. These physical factors can be modified, controlled, to achieve a desired effect by controlling growth room temperature, changing vessel bottom to influence internal humidity, modified the light quality and quantity to reach the optimum growth of plant cell cultures (Kozai and Smith, 1995; Chen, 2004). This high opportunity for physical conditions control is unique to in vitro plant cell growth and gives plant biotechnology distinct advantages for manipulating plant cells under his control. Hence, control the physical conditions, factors, is an awesome responsibility and an advantageous challenge for in vitro plant growth and as well as plant secondary metabolites’ production. Finally, in vitro physical factors are correlated to each other and it must be control all of them in the same growth room (Figure 3).
In this state of the art, physical conditions such as; temperature, culture vessels, and light will discuss.
Figure 3. Physical conditions of in vitro plant cell cultures
TopLight
Plant biotechnology laboratories, can be defined as an agriculture technology wherein the surrounding microclimate of any plant cells are fully controlled by normal and/or modern facilities during the cell life cycles. Hence, light is the most important physical factor in controlled environmental conditions, which is directly affect not only plant cell growth and development but also the production of plant secondary metabolites (Kendrick and Kronenberg 2012; Hart 2012; Kozai 2016).