Читать книгу Biotechnology of Fruit and Nut Crops - Группа авторов - Страница 61

Ara et al. (2000a) described the isolation, culture and regeneration of plantlets from protoplasts derived from embryogenic suspension cultures of ‘Amrapali’ (monoembryonic). After c.3–4 weeks in suspension, 1 g of embryogenic culture was incubated in 10 ml filter-sterilized growth medium consisting of B5 major salts, MS minor salts and organic components, supplemented with 0.3 M sucrose, 0.4 M mannitol, 0.1 M sorbitol, 2.74 mM glutamine, 1.0% cellulase, 1.0% hemicellulase and 0.5% pectinase with gentle shaking in darkness at 25°C. After 24 h, the digestion mixture was passed through a sieve (50 μm) to remove debris. The crude protoplast suspension was centrifuged for 5 min at 100 g, and the supernatant was discarded; this was repeated three times for 3 min for each centrifugation. The pellet was resuspended in 1 ml medium and layered on 3 ml sucrose solution (25% w/v) and centrifuged at 100 g for 7 min. Protoplasts were removed and cultured in the original medium, but modified to contain 0.18 M sucrose, 2.74 mM glutamine and 4.5 μM 2,4-D. Embryogenic cultures were recovered, and PEMs were plated on semisolid medium. Somatic embryos developed from PEMs following subculture to medium without 2,4-D, and plantlets were recovered.

Although many of the newly described Mangifera species have interesting environmental stress and pest resistance (see Section 1.1 Botany and History), their genetic isolation from mango is unknown. Somatic hybridization could provide a means for genetic recombination of the common mango with some of these species as a way of developing rootstock selections; however, it is unlikely that this approach would have utility for scion development, since somatic hybridization would result in polyploidy and introgression of useful traits into the common mango would be impossible due to genetic heterogeneity.