Sexual tetramorphism in Thymelaea hirsuta (Thymelaeaceae): Evidence of the pathway from heterodichogamy to dioecy
at the interspecific level.
in angiosperms may have arisen due to sexual selection, optimising the allocation of resources for reproduction (Bawa, 1980a; Givnish, 1982; Cruden, 1988; Willson, 1994).
The most extreme type of sex determination system is found where highly specialized sex chromosomes are found; this type of system usually promotes dioecy
in plants .
"A simple and reliable way to distinguish between male and female seedlings has long been sought not only for agricultural purposes but also to promote basic date palm studies, which have been hindered by dioecy
and long generation times," observed Malek.
It is considered that evolution of flowering plants with separate sexes (dioecy
) from an ancestral hermaphroditic condition (gynodioecy), has been sometimes accompanied by the development of sex chromosomes; in this scenario Fragaria virginiana (wild strawberry) is an example of the youngest sex chromosomes in plants in an intermediate stage between gynodioecy and dioecy
, providing a special opportunity to study sex chromosome genesis (Spiegler et al.
Most species have very large leaves, inflorescences and fruits, and also exhibit biological characteristics like very seasonal phenology and functional dioecy
which make it difficult to gather complete material.
plants--to colonize), perithecium, EES eesome (attractive to the eye), teesoo (Dhak flowers) ES Esau, thesis, obese IC ici, police IES gieseckite (variety pinite), Schoenflies (mathematician) IS isblink, artiste, piste, ambergris, kris ISS pelisse (a fur garment), camiss (a Muslim shirt) OES oestrin AES aestivation, quaestor EAS Easter, yeast, grease, increase EEC fleece, Greece EIS eis-blink, leister (a fishing spear) EYS keystone IEC piece IIS iisblink (a luminous appearance on the horizon) caused by the reflection of light from ice) OEC oecist (the founder of an ancient Greek colony), dioecy
IX Dix (the lowest trump in Bezique and other card games) short 's' sound followed by long 'E' sound....
prevents intraindividual self-pollination and is one of the most extreme inbreeding avoidance mechanisms (Ainsworth, 2000).
Beach JH, Bawa KS (1980) The role of pollinators in the evolution of dioecy
Most critically, allowing a certain amount of selfing by outcrossers (e.g., through "leaky" self-incompatibility or dioecy
) would remove the advantage enjoyed by selfers in a metapopulation.
Population genetics of partial male-sterility and the evolution of monoecy and dioecy
. Heredity 41:137-153.