Osmo- and cryotherapy of sugarcane (Saccharum spp. L.) shoot-tips infected with sugarcane mosaic virus (SCMV)

Abstract

In this work, we investigated the effect of different osmoprotective treatments and of cryopreservation using a droplet-vitrification (D-V) protocol to eliminate sugarcane mosaic virus (SCMV) of shoot-tips excised from in vitro propagated infected plantlets. Shoot-tips of sugarcane (Saccharum spp. L.) were precultured on semisolid MS medium supplemented with 0.3 M sucrose for 1 day, loaded in solution with 0.4 M sucrose and 2 M glycerol for 30 min and exposed to plant vitrification solution 2 for 15 min at room temperature prior to ultra-rapid cooling in liquid nitrogen. Virus indexing was performed by the DAS-ELISA immunoenzymatic test. The presence of SCMV was confirmed in the donor-plantlets derived of infected field material. No virus was detected in the regenerated plantlets from shoot-tips subjected to cryopreservation protocol. The progressive decrease in absorbances occurred from the first preculture treatment and no significant differences (P ≤ 0.05) were found with respect to following steps of D-V protocol. These results indicate that the osmotic dehydration treatments (osmotherapy) and cryopreservation (cryotherapy) may be potentially effective strategies to remove the SCMV from infected plants.

Keywords: Cryotherapy; Droplet-vitrification; Osmotherapy; Sugarcane mosaic virus; Virus eradication.

Fig. 1

Phytosanitary evaluation of SCMV by DAS-ELISA in sugarcane vitroplants derived of symptomatic field plants. Over the red dotted line, samples are positive to SCMV, below the red dotted line, samples are negative to SCMV

Fig. 2

Effect of the successive steps of droplet-vitrification protocol on removal of SCMV from plantlets of sugarcane (CP 72-2086 var.). Results are presented as averages (± SD) and significant differences were determined by Tukey test (P ≤ 0.05)