In this study, we investigated the chromosome breakage caused by gametocidal (Gc) chromosome 3C t and its interaction with the suppressor gene Igc1 (inhibitor of gametocidal gene 1) on wheat chromosome 3B. We demonstrated cytologically that patterns of 3C t -induced chromosomal fragmentation in microspores differed from patterns observed for other Gc genes. Uninuclear microspores of the monosomic 3C t addition line had high frequencies of micronuclei, possibly explaining its low fertility.

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... osome fragmentation was observed in prometaphase and metaphase of the first pollen mitosis in the monosomic 3C t addition line. Patterns of chromosome fragmentation were different from those previously reported for Gc chromosomes 2S of Aegilops speltoides, 4S sh of Ae. sharonensis and 2C cy of Ae. cylindrica; many chromosome fragments were observed in prometaphase of the first pollen mitosis in the monosomic 3C t addition plants. In anthers at the binuclear stage, many microspores at the uninuclear stage coexisted with normally developed microspores.