Herbivory affects male and female reproductive success differently in dioecious Silene latifolia

Abstract

In dioecious plants, reproductive efforts of male and female plants can be differentially affected by herbivory due to sex-specific allocation and re-modulation of resources. Here, we investigate the effects of foliar herbivory by the polyphagous species Spodoptera littoralis (Boisduval) (Lepidoptera: Noctuidae) on male and female reproductive traits of Silene latifolia (Poir.) (Caryophyllaceae). We set up experimental populations of male and female control and Spodoptera-infested plants and estimated flower morphology and phenology, and plant reproductive success. Herbivory did not affect floral traits involved in visual signalling to pollinators (flower size). Female reproductive success did not differ between Spodoptera-infested and control plants in terms of seed set and seed germination. On the other hand, Spodoptera-infested male plants produced fewer flowers than male control plants and maintained fewer flowers during flowering peaks. By experimental reduction in male flower number, we showed that male flower number is directly correlated with male reproductive success (pollen export to female flowers). This strongly suggests that male reproductive success is reduced after herbivory, whereas female reproductive success remains unaffected. The fact that females are more tolerant against herbivory is in accordance with sexual selection theory, which predicts that females, in contrast to males, are not selected for maximum investment in reproductive traits such as floral signalling, and should thus be more flexible in the allocation of resources.

Volatile Oils Discrepancy between Male and Female Ochradenus arabicus and Their Allelopathic Activity on Dactyloctenium aegyptium

“…Moreover, our data revealed the role of the gender of the plant on the phytochemical compositions including the VOs [ 39 , 40 ]. The richness of the compounds in the male plants compared to the female ones could be attributed to the fact that female plants invest less in chemical defense and more into biomass production than male plants [ 41 ], where the VOs can be considered a good indicator for the degree of chemical defense in plants due to its distinct variability with the biotic and abiotic stresses [ 22 , 42 ].…”

The relative contribution of diurnal and nocturnal pollinators to plant female fitness in a specialized nursery pollination system

“…bicruris interaction in the Mediterranean. Although our study investigated cost and benefits of the pollinator relationships only for the female function, Hadena can also provide a benefit for male function, which is even more dependent on pollinator efficiency ( Waelti et al 2009 ; Litto et al 2015 ). Potential conflicting selection between male and female flower functions may also help to explain why H. bicruris pollination is maintained also in the presence of other pollinators ( Prieto-Benítez et al 2017 ).…”

Do native and invasive herbivores have an effect on Brassica rapa pollination?

“…To apply herbivory on B. rapa individuals, we used the approach described in Litto et al . (). Briefly, feeding was limited to a single leaf by containing caterpillars in clip cages, made from Petri dishes, at the beginning of the bolting stage.…”

“…Herbivores can affect the number of flowers produced (Litto et al . ) and decrease the plant resources available for allocation to seed production, directly influencing plant fitness (Strauss et al . ; Mothershead & Marquis ; Knauer & Schiestl ), or can change the attractiveness of plants to pollinators, thus indirectly also influencing plant fitness.…”

“…; Litto et al . ; Knauer & Schiestl ). Although several studies have investigated the interactive effect of pollinators and herbivores on plant fitness (Galen & Cuba ; Gòmez , , ; Cariveau et al .…”