cuspidata displays little propensity for autogamy or selfing and is primarily self-incompatible
; however, this is not uncommon for the Asteraceae (Ferrer and Good-Avila, 2007) and perennials in general (Duminil et al., 2009).
These results suggest emasculation in controlled hybridizations, even though passion fruit is self-incompatible
, mainly for genetic studies.
species (Abdalla & Hermsen, 1972).
For example, if chrysanthemum is self-incompatible
, the small central disk florets can be also used for production of hybrid seeds, because it is unnecessary to remove them.
species (i.e., dependent upon vectors of pollen), longevity of flower is longer than in self-compatible ones that are able to self-fertilize early after anthesis of flowers (primack, 1985; schoen and Ashman, 1995).
Plants that will not self-pollinate may be self-incompatible
The relationship between the self-compatibility and self-incompatibility alleles is described as S > [S.sup.h] > s with S the self-incompatible
(thrum) allele dominant to both [S.sup.h] for self-compatible (homostyly) and to s, the self-incompatible
Whether and to what extent individual species form asexual clones has important consequences on milkweed reproductive biology studies since self pollinations among wholly or partially self-incompatible
clones may affect levels of fruit set.
For example, it is observed in the self-incompatible
, wind-pollinated tree Alnus firma (Murakami and Maki 1992).
Moreover, both diploid and tetraploid Galax appear to be self-incompatible
. Finally, fruit production is comparable across cytotypes, with both having increased seed production in hand-outcrossed flowers suggesting pollen limitation.
Cherry laurel is a self-incompatible
species and needs cross-pollination for fruit set according to our observations.
The four o'clock family (Nyctaginaceae) contains both self-compatible and self-incompatible