The influence of cation and gelling agent concentrations on vitrification of apple cultivars in vitro

Abstract

Shoot tips of 'York' and 'Vermont Spur Delicious' apples (Malus domestica Borkh.) were cultured in vitro to test the influence of K + , Mg + + and gelling agent concentrations on vitrification. These concentrations were 20.05, 14.05 and 8.05 mM K + , 1.5 and 3.0 mM Mg ~ +, 7.0 g/1 Difco Bacto agar and 1.0, 1.5 and 2.0 g/1 Gelrite. The lowest K + level produced a higher percentage of vitrified shoots, affected tissue appearance, reduced shoot number and shoot elongation and apparently altered shoot metabolic activity. Gelrite consistently produced vitrified leaves and stems, even though media gelled with 1.5 g/1 Gelrite presented the same apparent gel firmness as using 7 g/1 Difco Bacto agar, which did not induce vitrification. Less shoot elongation, fewer total shoots, and more usable shoots of 'York' were obtained on Bacto-agar, while similar but less noticeable effects were obtained with 'Vermont Spur Delicious'. The results presented here show that vitrification can be studied in a standardized system in which the only change is substitution of one gelling agent for another.

Influence of 6-Benzyladenine and gelling agent on the reduction of hyperhydricity in Tectona grandis L.

“…Similar results were reported for Malus domestica (Pasqualetto et al, 1988), Allium cepa (Jakse et al, 1996) and Scrophularia yoshimurae (Tsay et al, 2006). However, in agreement with Ivanova and Van Staden, (2010), we assumed that this effect of the gelling agent on the proliferation rate appears to be species-specific because more shoots were produced on media with agar of A. polyphylla.…”

“…Different authors refer to a similar positive effect of controlling hyperhydricity by increasing gelrite concentration in woody species such as Picea abies (Bornman and Vogelmann, 1984) and Malus spp. (Pasqualetto et al, 1988). However, in contradiction to our results, they refer to a negative effect on shoot proliferation.…”

Controle da vitrificação do cravo (Dianthus caryophyllus L.) in vitro

“…Resultados similares foram obtidos por PASQUALETO et al,(1988) no controle da vitrificação elevando a concentração de "Gelrite" para 6,0 g/1; e por DEBERGH et al 1981), ZIV et al (1983) e CHOUDHARY (1991) aumentando a concentração de ágar para 11 g/1, porém a esse tratamento seguiu-se também considerável redução na taxa de propagação e no comprimento das brotações. Esses resultados podem ser atribuídos à condição de baixo potencial de água (0) que afeta a disponibilidade de água e substâncias do meio de cultivo, dentre elas a citocinina (DEBERGH, 1983e DEBERGH et al, 1981 que demonstrou ser potente estimulante da vitrificação nas condições do experimento.…”

“…Os eventuais fatores da vitrificação têm sido atribuídos ao potencial osmótico (DEBERGH et al, 1981;HAKKAART & VERSLUIJS, 1983;PASQUALETO et al, 1988), concentração dos reguladores de crescimento, especialmente a citocinina (LESHEM et al, 1988a;1988b), umidade e a concentração salina do meio de cultura (DAGUIN & LETOUZÉ, 1986). Pára contribuir ao estudo dessa questão é que foi conduzido o presente trabalho tendo em vista determinar as condições controladoras da vitrifícação do cravo in vitro.…”

Polyamines, Gelling Agents in Tissue Culture, Micropropagation of Medicinal Plants and Bioreactors

“…However, their use may induce some problems during micropropagation. Gelrite®, for example, causes hyperhydricity and, in some cases, vitrification on regenerated shoots [35]. Hyperhydric shoots are characterized by a translucent aspect due to a chlorophyll deficiency, a not very developed cell wall and high water content.…”