Appendix 1.
Detailed analysis of chickpea chromosome sorting.
Flow cytometric analyses of DAPI-stained chickpea chromosomes resulted in
histograms of DAPI fluorescence intensity (flow karyotypes) comprising six and
seven peaks in desi and kabuli types, respectively (Figure 2). In the flow karyotype of
desi 'ICC 4958' (Figure 2A), peak I represented the smallest chromosome H; peak II
represented two metacentric chromosomes F and G; peak III represented
chromosome E; peak IV comprised chromosomes C and D, which could not be
discriminated morphologically and/or using FISH; peak V was assigned to
chromosome B, which carries the 5S rDNA locus, and peak VI was assigned to the
largest chromosome A, characterized by a secondary constriction with 45S rDNA
locus [1]. In the flow karyotype of kabuli 'CDC Frontier' (Figure 2B), peak I
represented the smallest chromosome H; peak II represented chromosome G; peak
III represented chromosome F; peak IV comprised chromosomes D and E, which
similar to desi could not be discriminated based on morphology and/or using FISH.
Peak V was assigned to chromosome C; peak VI was assigned to chromosome B,
which carries 5S rDNA locus and peak VII represented the largest chromosome A
characterized by a secondary constriction with a 45S rDNA locus [2]. These
analyses confirmed our previous observations on differences in DAPI fluorescence
of individual chromosomes between both types of chickpea [1, 2]. The differences
may reflect differences in chromosome size as observed by Ohri and Pal (1991) and
in this work (Table 4), as well as differences in chromosome organization.
Based on previous work [1, 3-5] it was possible to assign linkage groups LG1–LG8
to individual chromosomes of chickpea (Table 4). The genetic map of Thudi et al.
(2011) [3] was also used for anchoring of pseudomolecules Ca1 – Ca8 of the
reference genome sequence of kabuli chickpea [5], which are equivalent to
Ca_LG_1-8 on the desi reference genome assembly [6] (Table 4). To avoid
confusion, the nomenclature Ca1–Ca8 will be used here to describe the
pseudomolecules for both desi and kabuli.
1.
2.
3.
4.
5.
6.
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