R E V I E W: In Vitro Selection and Somaclonal Variation for Biotic and Abiotic Stress Tolerance

Abstract

As an alternative technology, plant improvement through somaclonal variation is expected to support conventional breeding. New superior variants with a better performance and more attractive texture could be obtained through this method. To enhance genetic variation, both physical and chemical treatments such as gamma ray (Co 60) and Ethyl Methane Sulphonate (EMS) compound could be applied. In particular for vegetative propagated plants, in vitro induced mutation is the most effective method to improve variation. For obtaining the desired characteristic of plant, in vitro selection is the best method due to its capability to manipulate the variation to the expected result. Therefore, by applying the selection agent to the media, plant tolerance to both abiotic and biotic could be acquired. Generally, the tolerance at the callus level at the specific selection agent is positively correlated with the tolerance at the plant level. At this point, PEG (polyethylene glycol) and manitol is chemical compound useful for drought tolerance, fusaric or filtrate is for fusarium wilt, A1Cl 3. 6H 2 O is for Al tolerance.

IIn Vitro Selection of Four Soybean Genotypes using PEG for Drought Tolerance

“…PEG could be applied for stimulating drought because it could inhibit water in such a way that no water is provided for somatic cell, except for the callus/ somatic cell which has particular mechanism for absorbing water. Only the tolerant callus which bears PEG media selection could increase its tolerance against drought stress (Lestari, 2006). The presence of survival ECs and SEs in this experiment were also demonstrated by histological examination as shown in Figure 4.…”

In vitro Tissue Culture, a Tool for the Study and Breeding of Plants Subjected to Abiotic Stress Conditions

“…The cause of variation is mostly attributed to changes in the chromosome number and structure. Generally, the term somaclonal variation is used for genetic variability present among all kinds of cells/plants obtained from cells cultured in vitro [14].…”

Variación somaclonal y selección in vitro con toxinas como herramienta en la búsqueda de resistencia a enfermedades en plantas: Revisión

“…La selección in vitro ha sido ampliamente utilizada a nivel mundial para la producción de germoplasma vegetal resistente o tolerante a enfermedades ( Jayasankar & Gray 2003) y limitantes abióticos ( Jayasankar 2005, Lestari 2006. Sin embargo, ha sido subutilizada en Colombia y Latinoamérica, según puede verse al hacer una búsqueda de literatura sobre el tema en la base de datos latinoamericana Scielo (www.scielo.org).…”

“…Por el contrario, la variación somaclo-nal de origen genético sí se transmite y expresa en la descendencia de las plantas regeneradas. Cuando esta capacidad intrínseca de variación de los cultivos crecidos in vitro es potencializada a través de la adición de un agente de selección al medio de cultivo, es posible obtener variantes "somaclonales" con tolerancia a ese agente de selección; esta técnica se denomina "selección in vitro" (Lestari 2006). …”

“…metales pesados, sales, herbicidas, fitotoxinas, virus, etc. ), de acuerdo con los fines que se persigan (Lestari 2006). En general, el tejido más ampliamente usado para la selección es el callo, aunque pueden utilizarse también otros explantes que conducen a una organogénesis directa.…”