The first map is made throughout the F

Linkage chart structure

_2:3 population between G. klotzschianum and G. davidsonii, a total of 728 polymorphic markers were used. The total map length was 1 cM, with an average ). This map was designated as map A. The second map, designated as map B, was derived by genotyping the F_2:3 population developed between G. thurberi and G. trilobum, and 849 polymorphic markers were used in the linkage map construction. The map size was 1 cM with an average marker distance of 1.193 cM. In both maps, it was observed that chromosome number two also annotated as D₅02 had the least map size of cM and cM in map A and map B, respectively. Interestingly, in both maps, chromosome D₅02 had a smaller map size but with the highest percentage of SD (Table 1). Similar results have been observed in other linkage maps in cotton (Yu et al. 2011; Li et al. 2016).

The consensus map was constructed by merging two data sets from the two genetic maps. A total of 1 492 markers were mapped onto the 13 linkage groups encompassing the 13 chromosomes, and only 85 markers remained unlinked. The diploid cotton species has 13 chromosomes, while the tetraploid cotton species has 52 chromosomes (Mendoza et al. 2013; Magwanga et al. 2018a). This work was based on the diploid cotton species of the D genome. The consensus map size was 1 cM with an average marker distance of 1.037 cM. Even though the map size was relatively smaller than map A, the marker interval was low, which improved the precision of the consensus map. From the consensus map, we observed that Chromosome D₅02 had the highest percentage of SD with 58.6%, followed by Chromosome D₅07 with 47.9%. Chromosome D₅01 had the highest number of markers (143), while Chromosome D₅02 had the least number of markers (58) (Table 1). Most of the markers mapped on the consensus map were found to be contributed by map B rather than map A. A total of 797 markers from map B were mapped on the consensus map accounting for 53.4% while only 695 markers (46.6%) were from map A. The chromosome with the highest number of markers (143)was Chromosome D₅01 while the chromosome with the least number of markers (58) was Chromosome D₅02 (Fig. 1).

Consensus hereditary linkage chart symbolizing thirteen linkage categories of brand new diploid cotton fiber regarding D genome, created from map A good (G. klotzschianum and Grams. davidsonii) and you can chart B (Grams. thurberi and you will Grams. trilobum). Indicators during the green font show chart B if you’re indicators during the red font depict chart Good. Brand new markers into the black represent indicators translocated off their chromosomes within brand new maps; the brand new markers during the SDR is italicized and you may committed. a-m: show the individual chromosomes, off chromosome step 1 in order to chromosome 13

Segregation distortion (SD) research

In map A, out of the 728 markers mapped, 159 markers were distorted accounting for 22.2%, and the highest SD was observed in Chromosome D₅02 with 76.1% followed by Chromosome D₅07 with 40.7%. The SDRs were located on Chromosome D₅02, D₅05, D₅07, and D₅08. Chromosome D₅02 had the largest SDR, while Chromosome D₅07 had the highest number of SDR.

It was observed that the alleles in SDR were skewed towards a particular parental line, like that in Chromosome D₅02 towards the female parent (G. klotzschianum), and in Chromosome D₅07 towards the heterozygosity (Kirungu et al. 2018). In the second genetic map B, there was a slightly lower number of distorted markers, with only 135 accounting for 15.8%, and the highest two segregation distortions were observed in Chromosome D₅02 and Chromosome D₅07 with 42.8% and 38.3%, respectively (Table 1). Chromosomes that had the SDRs were D₅01, D₅02, D₅06, D₅07, D₅09, D₅10, and D₅11. Moreover, the largest SDR was located on Chromosome D₅02, while Chromosome D₅07 had https://datingranking.net/local-hookup/las-vegas the highest number of SDR.