TISSUE-CULTURE OF ANNONA SPP (CHERIMOYA, ATEMOYA, SUGAR APPLE AND SOURSOP) - A REVIEW

Most commercially important Annona species are currently propagated th rough grafting and budding. However, seedling rootstocks vary in vigor and disease resistance and the consequent variation in scion growth h as major effects on yield. With the exception of a few cultivars, clon al propagation of cherimoya, atemoya, sugar apple and soursop by cutti ng or air layering has not been very successful. Root and shoot organo genesis has been successfully induced in sugar apple anther, endosperm and leaf explants as well as in cherimoya hypocotyl, petiole, interno de and nodal cuttings. Hypocotyl and nodal cuttings of atemoya and hyp ocotyl explants of soursop have also proved suitable for in vitro cult ure. Tissue-cultured shoots, especially those obtained from hypocotyl and nodal segments of some Annona species have been successfully roote d. The results of studies on the prevention of browning during tissue culture, and on induction of autotrophy are reported.