Formation of nonviable progeny after hybridization of flowering plants
Triploid block is a phenomenon describing the formation of nonviable
progeny after
hybridization of
flowering plants that differ in
ploidy. The barrier is established in the
endosperm, a nutritive tissue supporting
embryo growth.[1][2] This phenomenon usually happens when
autopolyploidy occurs in
diploid plants. Triploid blocks lead to
reproductive isolation. The triploid block effects have been explained as possibly due to
genomic imprinting in the endosperm.[1] Triploid block can be partially ovecome by chemical treatment with 5-Azacytidine.[3]
References
^
abKöhler, C; Mittelsten Scheid, O; Erilova, A (Mar 2010). "The impact of the triploid block on the origin and evolution of polyploid plants". Trends in Genetics. 26 (3): 142–8.
doi:
10.1016/j.tig.2009.12.006.
PMID20089326.
^Marks, G. E. (1966). "The Origin and Significance of Intraspecific Polyploidy: Experimental Evidence from Solanum chacoense". Evolution. 20 (4): 552.
doi:
10.2307/2406589.
PMID28562905.