Micropropagation of berry crops for creation of germplasm cryobanks

Micropropagação de fruteiras para criação de criobancos de germoplasma

Abstract

One of the main stages of cryopreservation of meristematic tissues in vegetative plants is a clonal micropropagation, which includes isolating the explants of the raw material in vitro and optimizing the culture medium for micropropagation. As the result of our studies, the optimal periods for in vitro micropropagation are: first - isolation of explants from initiated shoots of dormant buds (blackcurrants and raspberries) in January-March; the second - from actively growing shoots (blackcurrants and raspberries) in May-June, from the formed mustache (strawberry) in July-August. The optimal drugs for sterilization of raspberry explants are: a) 0.1% HgCl₂ (6 min), then 3% H₂O₂ (15 min); b) chlorine-containing bleach «Domestos» in the dilution of H₂O 1:9 (10 min). For blackcurrant: a) 0.1% HgCl₂ (5 min) in combination with 0.1% fungicide “Topaz” (30 min); b) 0.1% HgCl₂ (5 min) in combination with the treatment with KMnO₄ (30 min); c) “Domestos” in the dilution of H₂O 1:5 (20 min). For strawberry: a) 0.1% HgCl₂ (6 min) followed by treatment with 3% H₂O₂ 10 (min); b) 1% deochlor (7 min), 3% H₂O₂ (10 min); c) “Domestos” in the dilution of H₂O 1:5 (8 min) with subsequent treatment 0,1% HgCl₂ -7 min, then 0,20 mg/l КМnO₄ - 30 min. Optimal compositions of culture media for micropropagation of blackcurrant - Murashige and Skoog (MS) medium with 0.5 mg L^-1 BAP, 0.5 mg L^-1 GA₃, 0.1 mg L^-1 IBA and 20 g L^-1 glucose. For raspberry -MS medium with 0.5 mg L^-1 BAP, 0.1 mg L^-1 IBA, 10 mg L^-1 iron chelate and 30 g L^-1 sucrose. For strawberry - MS medium with 0.3 mg L^-1 BAP, 0.01 mg L^-1 IBA, 0.2 mg L^-1 GA₃, 10 mg L^-1 iron chelate and 30 g L^-1 sucrose. Based on these studies, the cryobank was created, which include the germplasm of in vitro meristematic tissues in 66 cultivars, hybrids and wild-growing forms of blackcurrant, raspberry and strawberry. Therefore, the aim of the research was to obtain aseptic plants, clonal micropropagation and the creation of a cryogenic collection of germplasm based on the developed technology.

Keywords:
berry crops; micropropagation; cryobank; germplasm