Improved micropropagation protocol for pear rootstocks of the OH×F series and a new selection

A. Castillo, D. Cabrera, P. Rodríguez, R. Zoppolo
Pear is one of the most important temperate fruit crops. Uruguay aims at producing pears of high quality to reach regional markets as well as those of the Northern Hemisphere. Nevertheless, local climate variability and soil conditions frequently pose sanitary challenges for pear production, mainly in the south of the country, where the major pear producing area is located. Some new rootstocks of the series Old Home × Farmingdale (OH×F, Pyrus communis L.) were introduced from the pear germplasm collection of the US Department of Agriculture, National Clonal Germplasm Repository - Corvallis (NCGR) to the country with the aim of evaluating new materials and trying to identify those better adapted to local soil and weather conditions. To reach a reasonable number of plants in the shortest possible time, in vitro multiplication system was selected. This work was carried out to develop a protocol of in vitro propagation of different rootstocks, in order to generate faster plantlet production with high quality. A group of five different rootstocks from the OH×F series was selected: OH×F 40, OH×F 69, OH×F 87, OH×F 217, OH×F 333, and a local material identified as 00LBPrSJ. All genotypes were cultured in the same culture medium, a modification of the MS mineral salts. OH×F 217 and OH×F 69 exhibited the lowest multiplication rate in the culture medium used and produced less than two shoots per explant compared with OH×F 40 that produced more than five. The local selection had an average performance with four shoots per explant. Rootstocks showed differences in percentage of rooting and the survival during the acclimation which suggests the potential development of genotype-specific protocols.
Castillo, A., Cabrera, D., Rodríguez, P. and Zoppolo, R. (2021). Improved micropropagation protocol for pear rootstocks of the OH×F series and a new selection. Acta Hortic. 1303, 107-112
DOI: 10.17660/ActaHortic.2021.1303.16
in vitro, shoot proliferation, tissue culture, rooting

Acta Horticulturae