Propagation Studies on Clonal Rootstocks of Apple Malus domestica Borkh

Abstract

newline The present investigations entitled Propagation studies on clonal rootstocks of apple (Malus × domestica Borkh.) was carried out at Plant Tissue Culture Laboratory, School of Biotechnology (SBT) and Tissue Culture Laboratory, Advanced Centre for Horticulture Research (ACHR), Udheywalla of Sher-e-Kashmir University of Agricultural Sciences and Technology of Jammu to standardize the in vitro propagation protocol of clonal apple rootstocks MM106 and MM111 during 2018. The shoot tip and nodal segment used as explants were taken from MM106 and MM111 mother block maintained at Regional Horticulture Research Sub Station, Bhaderwah, SKUAST-Jammu. Results from the present investigation revealed that different treatments of mercuric chloride (HgCl2) and sodium hypochlorite (NaOCl) showed a significant effect on per cent aseptic and per cent survival of cultures. Treatment of 0.1 per cent HgCl2 for 4 minutes resulted in maximum aseptic and survival of cultures during all the months of study. MS medium supplemented with 10 mg/l polyvinyl pyrrolidone was found to be the best antioxidant medium for reducing phenolic exudation from the excised portion of the explants and for culture establishment of explants. Nodal segments of clonal apple rootstock MM106 and MM111 resulted in maximum percentage of culture establishment i.e. 32.22 per cent and 47.88 per cent, respectively as compared to shoot tip explants. MS medium supplemented with 1.0 mg/l BAP + 1.0 mg/l GA3 was found to be the best medium for culture establishment in minimum number of days. Nodal segments were found to be more suitable explants than shoot tips which resulted in maximum culture establishment percentage of 57.77 per cent and 76.66 per cent in 26.33 days and 25.40 days for rootstocks MM106 and MM111, respectively. However, different media combinations also showed a significant influence on in vitro shoot proliferation. Nodal segments of clonal apple rootstocks MM106 and MM111 were found to be better in comparison to shoot tip explants wherein