Regeneration of virus‐free grapevines using <i>in vitro</i> apical culture

Abstract

SUMMARY Fragmented shoot apex culture of grapevine has been demonstrated to regenerate plants free from the graft‐transmissible diseases leafroll, yellow speckle, fleck and summer mottle. This technique in combination with heat therapy of the cultures has also produced vines free from fanleaf virus. Regenerated plants free of yellow speckle were consistently obtained if cultures were incubated at 27/20 °C but not if incubated at 35 °C. The possible ways that the in vitro elimination of these diseases was achieved are considered.