4.5. Expression of andromonoecy
Andronomonoecy is rare in angiosperms, but it frequently found in
Apiales. The feature derived several times independently in this family
(e.g. Schlessman 2010). The higher percentage of perfect flowers
observed in terminal umbels. The percentage of staminate flowers
increases with age in higher branch orders (Reuther and Claßen-Bockhoff
2010, 2013, Ajani and Claßen-Bockhoff 2021). The experimental treatments
showed that andromoneny genetically fixed even under simulating
environmental factors like removing the terminal umbel. Based on these
data, the andormonoecius species respond to the environment easily by
transforming of staminate to perfect flowers. It occur in last stages
which allowing the plants easily respond to the environment changes
(Reuther and Claßen-Bockhoff 2013). It exactly found in Dorema
aucheri and Ferula hezarlalehzarica , two perennial endemic
andromonoecious in Iran (Ajani et al. 2016).
In Di. persica, the initiation of sexual morphs show striking
resemblances except ovule abortion in staminate flowers that is a main
reason for expression of andromonoecy. The staminate flowers, therefore,
cannot serve as substitution for perfect flowers under environmental
changes that allowed the plant to set only one large fruit in each
umbellet. Like Echinophora spinosa , the degree of fruit set is
likely low (≤10%) due to constant sexual morph flowers (90% staminate)
when compared by andromonoecius species (Reuther and Claßen-Bockhoff
2010). The sexual ratio of four staminate to one perfect flower (Doust
1980), therefore, not confirmed in Di. persica . The low fruit
set, however, is not a threatening factor since the large and dense
populations are growing without destructive factors (own observation).
This finding previously confirmed in Red Data Book of Iran where its
conservation status categorized as “low risk” species (Jalili and
Jamzad 1999).
In andronomoecous species, the role of staminate flowers is donating
pollen grains and attracting the pollinators (Schlessman et al. 2004,
Web 1981). In D. persica , it may likely intensified by diverse
club-like organs which attract manifold insects specially Coleoptera
(own observation). The functional role of the club-like organs, however,
needs comprehensive field studies in future.