Shortcut to long-distance developing of a tissue culture medium: micropropagation of mature almond cultivars as a case study

Abstract

IntroductionEvidently the development and the use of a defined tissue culture medium are among the most important factors that affect explant morphogenic reactions and the success of in vitro studies. The growth of cultures (

Artificial Neural Network Genetic Algorithm As Powerful Tool to Predict and Optimize In vitro Proliferation Mineral Medium for G × N15 Rootstock

“…The wide application of MS, WPM, and QL media as standard growth media for all Prunus rootstocks, for the purpose of micropropagation and as a source of leaf explants for transformation and regeneration, has given the false impression that these rootstocks would be difficult to culture if they do not grow well on MS, WPM, and QL media. Previous studies with diverse Prunus genotypes confirmed that the so-called standard media require an optimization of nutrients for the successful micropropagation of the unique rootstock or cultivar of Prunus (Nas et al, 2013; Nezami Alanagh et al, 2014). Our initial studies showed that the NH 4 ${\text{NO}}_3^{-}$ and ${\text{KNO}}_3^{+}$ components of the MS medium were inadequate for optimal growth and multiplication of G × N15 rootstock (Arab et al, unpublished data).…”

“…The majority of Prunus micropropagation studies of Prunus rootstocks have used a single mineral nutrient formulation to determine the effects of various PGRs (Andreu and Marín, 2005; Ruzic and Vujovic, 2008). Unfortunately, because of the complexity of interactions between medium constituents, it is very difficult to determine the optimum levels of minerals and organic compounds for a culture medium (Nas et al, 2013). The wide application of MS, WPM, and QL media as standard growth media for all Prunus rootstocks, for the purpose of micropropagation and as a source of leaf explants for transformation and regeneration, has given the false impression that these rootstocks would be difficult to culture if they do not grow well on MS, WPM, and QL media.…”

“…Our earlier studies also showed that replacing Ca(NO 3 ) 2 with CaCl 2 can improve in vitro multiplication of G × N15 (Arab et al, unpublished data). Moreover, Prunus rootstocks come in a wide variety of genotypes, with varying nutritional requirements, which makes the medium optimization process more complex and difficult (Espinosa et al, 2006; Canli and Tian, 2008; Ruzic and Vujovic, 2008; Nas et al, 2013; Nezami Alanagh et al, 2014). There are many possible approaches for optimizing the culture medium for plant tissue culture, but there is not a universal approach that can be used either to develop or to modify a micropropagation medium for a large number of species.…”

“…As a result, time-consuming and complex factorial designs have been applied to optimize the culture medium (Murashige and Skoog, 1962; Niedz and Evens, 2007; Petri and Scorza, 2010). Due to the difficulties involved in developing new formulations, medium development has typically involved comparisons of established media to find one that provides adequate growth and development (Bell et al, 2002), but some researchers have suggested that the levels of medium components can be optimized based on composition of growing whole plants or developing tissues or raw kernels (Staikidou et al, 2006; Ashrafi et al, 2010; Nas et al, 2013). It is likely that more than one medium will be needed for optimum growth of Prunus species and cultivars because when MS, EM, and QL media were used for the in vitro culture of G × N15, abnormal growth, hyperhydricity, necrosis and discoloration were observed at the multiplication stage, whereas on WPM medium, most shoots were healthy but grew much more slowly (Arab, unpublished data).…”

“…However, the optimized culture medium YAS was superior to MS, EM, QL, and WPM with respect to the three growth parameters: Shoot length, shoot number per cultured explant and productivity. Nas et al (2013) reported that productivity may be a helpful growth parameter to consider for selecting the best medium. Higher productivity indicates a high number of long shoots that contain more axillary buds.…”