A robust method for haploid sugar beet in vitro proliferation and hyperhydricity reduction

Abstract

Sugar beet is recalcitrant to in vitro tissue culture. Usually, proliferation of in vitro cultured rosette explants is a prerequisite for micropropagation. Although hormonal treatments can induce proliferation in sugar beet rosette explants, they may also result in some side effects. In vitro culture of sugar beet explants and some hormonal treatments make them more prone to hyperhydricity. Effects of media with different concentrations of 6-benzylaminopurine (BAP) and kinetin (Kin) on the proliferation and hyperhydricity of haploid sugar beet explants were investigated. It was observed that 0.2 mg L -1 Kin, with a reasonable amount of proliferation and minimum rate of hyperhydricity, performed better than BAP in different concentrations and combinations. The effect sizes of the treatments on the dependent variables were large. The correlation between proliferation and hyperhydricity of the treated explants was statistically negative and the association was large. However, the hormonal treatments without BAP or with the lowest amount of it produced the highest proliferation rate with the least hyperhydricity. The coefficient of determination was R 2 quadratic = 0.885. The results suggest that, in comparison with BAP, Kin is a potent plant growth regulator for the proliferation of sugar beet haploid explants that causes the least hyperhydricity. Although explants proliferated better in the presence of 0.01 mg L -1 BAP in combination with Kin than under Kin alone, the hyperhydricity of the proliferated explants decreased their suitability for in vitro propagation.

The effects of proline on in vitro proliferation and propagation of doubled haploid sugar beet (Beta vulgaris)

“…The ES of the independent variables estimated with epsilon-squared was ε² = 1.0. Although incorporating CKs into sugar beet in vitro culture medium generally induces propagation, at the same time it can lead to hyperhydricity and necrosis (Klimek-Chodacka and Baranski, 2013;Pazuki et al, 2017). However, our observation indicated that proline-treated explants were all free of those symptoms.…”

“…Since sugar beet in tissue culture medium generally is a rosette plant, it is normally propagated by dividing proliferated shoots. However, sometimes proliferation is not in a favorable pattern to propagate more propagules (Pazuki et al, 2017). Among some nonstructural carbohydrates and osmoprotectants, in comparison with roots, proline concentration in leaves (as a sink) increased more than any other ones (Hagedorn et al, 2016).…”

“…After doubling the chromosome number, all the explants were propagated, randomly segregated, and subcultured on 45 ± 5 mL of medium in Magenta boxes containing MS medium supplemented with 10 g L -1 sucrose and 0.2 mg L -1 kinetin and solidified with 6.5 g L -1 Phytagel. This medium was chosen based on a previously conducted experiment to control the hyperhydricity of sugar beet in vitro explants (Pazuki et al, 2017). The explants, which were propagated, were divided into new explants with three leaves using a scalpel and forceps.…”

“…The protective role of proline under biotic and abiotic stress conditions has been demonstrated in many studies (Szabados and Savoure, 2010). The effects of two different CKs have been previously investigated to efficiently improve sugar beet in vitro propagation (Pazuki et al, 2017). To the best of our knowledge, the role of exogenous proline in in vitro proliferation and propagation has not been studied.…”

Evaluation of Genetic Distances Correlations Among Sugar Beet Genotypes (Beta Vulgaris L.)

“…Increasing environmental problems and anthropogenic influences leads to narrowing borders of tolerance and reducing crops resistance to abiotic and biotic stress factors (Strausbaugh et al, 2010;Kito et al, 2017). Therefore, in recent years, the development of crop production is focused on creating agro-ecosystem capable of fast responding to stressful effects and subsequent self-regulation (Bray, 2002;Zhuchenko, 2008;Pazuki et al, 2017).…”