Sex chromosomes in land plants can evolve as a consequence of close linkage between the two sex determination genes with complementary dominance required to establish stable dioecious populations, and they are found in at least 48 species across 20 families. The sex chromosomes in hepatics, mosses, and gymnosperms are morphologically heteromorphic. In angiosperms, heteromorphic sex chromosomes ...

Several hypotheses have been proposed to explain the persistence of dioecy despite the reproductive advantages conferred to hermaphrodites, including greater efficiency at purging deleterious mutations in the former. Dioecy can benefit from both mutation purging and accelerated evolution by bringing together beneficial mutations in the same individual via recombination and shuffling of genotype...

Angiosperms are the most diverse group of land plants which provides fruits, food, seed for cultivation and material for hybridization purpose etc. Approximately 90% of all angiosperm species have hermaphrodite (bisexual) flowers and the remaining, onetenth are either monoecious (male and female flowers are separate but grow in same plant) or dioecious (male and female flower grow on different ...

The evolution of dioecy from hermaphroditism allows for avoidance self-pollination, and its evolutionary background has been investigated both experimentally theoretically since it was first proposed by Darwin. To reproduce this evolution, we screened hermaphroditic mutants Silene latifolia using heavy-ion beam or γ-ray irradiation characterized the phenotypes their floral organs. Our scatterpl...

A one-locus two-allele model of trioecy (presence of hermaphrodites, males and females in one population) is considered, in order to study the conditions for the persistence of this system. All possible assignments of the three sex types to the three genotypes are considered. This leads to three different modes of inheritance of trioecy, namely (a) females heterozygous, (b) males heterozygous a...