01766naa a2200157 a 450000100080000000500110000800800410001910000160006024500530007626000090012952013330013870000160147170000150148770000200150277300860152216518442004-04-14       1998    bl uuuu     u00u1 u    #d1 aWOODWARD, B  aCassava a method for the elimination of viruses.  c1998  aAbstract: Cassava (Manihot esculenta Crantz) is a tropical crop grown for its thickened tuberized roots. Since cassava is propagated vegetatively by cuttings derived  from stems of field-grown plants, diseases are easily transmited. This is also true for the spread of which cassava is susceptible. In Africa, large yield losses occur due to African cassava mosaic diseases (ACMD), which is caused by the african Cassava Mosaic Virus (ACMV). The aim of project is to produce disease-free cassava material for research and for distribution as planting material. An in vitro thermotherapy technique was tested for its potential to eliminate viruses in cassava, since convetional techniques may be expensive and time consuming. Various South African cassava cultivars were indexed for viruses using an ELISA technique, after which shoot tip cultures of the plants were subjected an in vitro thermotherapy treatment for 6 weeks, followed by meristem culture. Plantlets regenerated from meristems were acclimatized in the greenhouse using different planting media. Plants were then evaluated for symptom development and indexed  again using ELISA techniques. Results indicated a high success rate in the eradication of viruses from infected plants, and have show that this may be an ideal method to use for cassava virus elimination.1 aSTEYN, A. E1 aJERICHO, C1 aTHOMPSON, G. J.  tRevista Brasileira de Mandioca,Cruz das Almasgv.17, p.45, nov, 1998, Suplemento.