Floral traits predict pollination syndrome in Syzygium species: a study on four endemic species of the Western Ghats, India

Abstract

Pollination ecology and the breeding system of four endemic species of Syzygium (S. heyneanum, S. travancoricum, S. laetum and S. mundagam) of the Western Ghats, India are investigated. The floral traits are used for ordination analysis to understand if the species form any cryptic groups and whether this grouping predicts the pollination syndrome and the breeding system. Pollinators were distinguished from frequent visitors by studying their efficiency to transfer pollen to the stigma or induce fruit set following their exclusive visit to virgin flowers. The species formed two groups in the ordination map: the S. heyneanum and S. travancoricum group and the S. laetum and S. mundagam group. The flowers of studied species attracted 3–23 species of animals during the day, but none were encountered during the night. Flowers of S. heyneanum and S. travancoricum were visited by a large number of insect species of which only a limited number turned out to be the pollinators. S. laetum and S. mundagam attracted two bird species apart from a few insect species. In S. laetum, although birds did not bring about pollination directly, their visits facilitated anemophily by releasing pollen to the air by causing physical disturbance to the flowers. In S. mundagam, both birds and wind were involved in pollination. S. heyeanum and S. travancoricum were fully self-compatible, whereas S. laetum and S. mundagam were partially self-compatible.

Geographic isolation, pollination syndromes, and pollinator generalization in HimalayanRoscoeaspp. (Zingiberaceae)

“…Closely related plant species that share common functional groups of pollinators are thought to have convergent floral traits, largely driven by pollinator‐mediated selection (Schemske , Patterson and Givnish , Anderson and Johnson , Kuriakose et al. ). Reversely, differences in floral trait expression among congeners are thought to have been the consequences of adaptation to different pollinators (Schemske and Bradshaw , Muchhala ).…”

“…, Kuriakose et al. ). The selection pressure exerted by a floral visitor primarily depends on its behavior and frequency of visit (Sinu and Shivanna , b).…”

“…, Kuriakose et al. , ). Some authors have suggested that pollination syndromes are not reliable to predict the potential pollinators (Hingston and McQuillan , Hargreaves et al.…”

“…, Kuriakose et al. , ). The mounting evidence suggests that plant species with specific pollination syndromes are often pollinated by several types of floral visitors, and in some cases, the contribution of generalized pollinators outweighs the contribution of pollinators predicted by the floral syndromes (Waser et al.…”

The best of two worlds: ecology and evolution of ambophilous plants

“…Some authors consider ambophily to be a separate pollination syndrome (Gan et al ., 2013; Ríos et al ., 2014; Kuriakose, Sinu & Shivanna, 2018) while others classified ambophily as a pollination mode within different syndromes (Costa & Machado, 2012; Gong et al ., 2016). To categorise ambophily as a pollination syndrome, a set of common functional flower traits must be present that distinguish ambophilous species from species with other pollination syndromes (Fægri & van der Pijl, 1979).…”