Programmed Cooling and Vitrification Method Applied to the Germplasm Preservation of Eriobotrya Plants

Abstract

Long-term cryopreservation of germplasm is of great importance to maintaining genetic resources. A cryopreservation technology system has not yet been established for Eriobotrya, an important fruit tree in the Rosaceae. In this study, Eriobotrya plants were used as test materials for the following purposes: to study different types of vitrification solution, compare different methods involving programmed cooling vitrification and rapid freezing vitrification; and evaluate the effects of vitrification solution loading time, low-temperature acclimation culture, dark culture, and cryoprotectant use in preculture medium for ultra-low-temperature preservation of Eriobotrya germplasm resources. Plant vitrification solution 1 had the best comprehensive effect on different vitrification solution tests. The programmed cooling and vitrification method yielded a certain survival rate with different vitrification solutions and materials, but the survival rate under the rapid freezing method was 0%. The longer the vitrification solution was loaded, the higher the survival rate. The most suitable time for dark culture of Eriobotrya plants after cryopreservation was 20 days. The preculture medium supplemented with 5% dimethyl sulfoxide resulted in significantly higher preservation than the control medium, and the optimal sucrose concentration was 0.3 mol⋅L−1. A stable, high-survival, and novel cryopreservation procedure for loquat plants was established. The operating procedures are described in a procedural and standardized manner. These findings provide a theoretical basis for research of the cryopreservation of germplasm resources of Eriobotrya plants.