FIGURE 7.

Quantification of bivalents and chromosome fragments in different alleles. (A) Quantification of bivalent and univalent in different alleles. The number of bivalents or univalents in each allele was counted in the metaphase I cells. For those metaphase I cells contain entangled chromosomes were classified as entangled. For those metaphase I cells contain both entangled chromosomes and univalents were classified as univalents and entangled. For each allele, the counted cells are from about 20 plants. (B) Quantification of chromosome fragmentation levels in different alleles. For each allele, the anaphase II and telophase II cells were observed after DAPI stained chromosome spreads and centromeric FISH. DAPI stained bodies without centromere signal were taken as chromosome fragments. Chromosome fragmentation levels are divided into four categories: 0 (no chromosome fragmentation), 1–5 (1–5 fragments per cell), 6–10 (6–10 fragments per cell) and >10 (more than 10 fragments per cell). For each allele, the counted cells are from about 12 plants.