Genetic Makeup of Pyrus  

GENETIC MAKEUP OF PYRUS

People from the sort Pyrus are for the most part diploid in nature. The haploid number of chromosomes is x=17 and the diploid number is 2n=34. Due to the small size of their chromosomes, 0.5 to 1.5µm apple and pear chromosomes are difficult to differentiate. Common pear is diploid in nature (2n=34), while many cultivated members are polyploid or aneuploid. The diploid number of chromosomes (2n=34) has raised controversies about the molecular derivation of Maloideae.

Various assumptions were put forward on the auto or allopolyploid origin of Maloideae. Multiple results indicate that P. ussuriensis is triploid and diploid, Pyrus armeniacefolia is triploid, and most P. bretshneideri cultivar are diploid, triploid, and tetraploid. P. pyrifolia has been reported as diploid and triploid in nature. Tetraploid, triploid, and diploid genetic origins were also reported in P. phaeocarpa, P. sinkiangensis, P. pashia P. betulaefolia, P. xerophilus P. hopeiensis, P. pashia, P. serrulata, and P. calleryana. Chinese pear shows variation in chromosome number and is used in yield production, genetic variability, and breeding purposes.

A single S-locus controlled gametophytic self-unsuitability makes the members of the Pyrus family highly heterogeneous, creating hybrids of high richness and self-infertility.

Conclusion

The morphology of Pyrus is intriguing, and understanding it can help breeders create new cultivars. A diverse range of Pyrus speciescan be further evaluated for genetic diversity and breeding purposes, contributing to the pear industry's economic significance.

1: PYRUS COMMUNIS