SOMACLONAL VARIATION IN 3 ARGENTINEAN VARIETIES OF TRITICUM-AESTIVUM WITH DIFFERENT KARYOTYPIC INSTABILITY

Three cultivars of wheat showing different levels of spontaneous karyo typic instability were studied regarding their stability in vitro for a number of characters, i.e. chromosome structure, gliadin pattern, gl ume and grain colour, awn type, chlorophyll pigmentation and plant mor phology. The progenies of somaclones derived from immature embryos of both aneuploid and euploid plants were used in this study along with f oundation seeds and a large number of their sexual progeny in order to discriminate between pre-existent variability and any novel variation induced by the in vitro culture. Only one translocation not described before and a new gliadin pattern were detected which could be ascribe d to the effects of tissue culture, suggesting that this technique is not effective for inducing novel variation for breeding purposes in wh eat.