Unreduced microspores in cassava, Manihot esculenta crantz clones

Abstract

Nine indigenous Costa Rican cultivars of cassava were studied cytogenetically to detect unreduced microspores. Out of these nine clones, four showed about 1% triads among the tetrads 1–1.3%. One of them also showed 3.7% diads. The meiotic study revealed presence of sectorial chimera in one of these clones. This is the first report of sectorial chimera in cassava. This chimera formed two parallel sectors in the inflorescence, where sedor had regular chromosome pairing, and the other sector showed predominant chromosome asynapsis.