Self-Compatibility and Reproductive Success of Oenothera drummondii subsp. drummondii: Is It Similar between Native and Non-Native Populations?

Abstract

The mating system of plants widely distributed can change in native range but also in non-native habitats. Oenothera drummondii, native to the coastal dunes of the Gulf of Mexico, has been introduced to Europe, Africa, Asia and Oceania. Hand self- and cross-pollination were performed to determine compatibility and to compare fruit set, fruit weight, seed set and germination characteristics from natives and non-natives populations and a comprehensive integral reproductive success index (IRSI) was built. Oenothera drummondii exhibited high self-compatibility and mixed reproductive systems in all populations. Characteristics of fruits and seeds from self- and cross-pollination varied within and between native and non-native populations and some had a positive clinal variation in the native range. The IRSI was sensitive to changes of fruit set, seed set and final germination of both self- and cross-pollination, showing differences between native populations. Differences in characteristics of fruits and seeds in the native and non-native ranges suggest the occurrence of distinct selection factors. The mixed reproductive system of O. drummondii suggests it can take advantage of local visitors in the native range, but also can provide advantages for the establishment at non-native sites giving the opportunity to interact with local flower visitors.

Range Shifts in the Worldwide Expansion of Oenothera drummondii subsp. drummondii, a Plant Species of Coastal Dunes

“…Latitude also performs an important role in self-compatibility and germination (rate and final germination), which are reduced in lower latitudes, and increase in higher latitude for both native and non-native distributions. The Australian populations studied in Gallego and Franco [40], showed rates of self-compatibility similar to those of other non-native populations and native populations located at similar latitudes. Therefore, these reproductive characteristics may contribute to the successful invasion of O. drummondii in non-native areas [40].…”

“…The Australian populations studied in Gallego and Franco [40], showed rates of self-compatibility similar to those of other non-native populations and native populations located at similar latitudes. Therefore, these reproductive characteristics may contribute to the successful invasion of O. drummondii in non-native areas [40]. At global scale, it is possible that the introduction of O. drummondii from its native areas has been as stowaways in the ground-ballast of merchant shipping.…”

“…Studies performed in southern Spain indicate that the successful invasion of O. drummondii is mainly explained by some features that are considered advantages for the colonization of new habitats [87]. On a local scale, the reproductive characteristics of the species, a mixed-mating system, allows the flowers to interact with the local fauna (bees and sphinxes) [40]. It also has a high production of small seeds, and has established mutualistic seed dispersal relationships with native hares and rabbits [39].…”

“…O. drummondii grows in its native area in the back beaches and the first dune ridges with humid subtropical and wet tropical climates (Cfa, Aw, Am, BSh) according to the Köppen-Geiger classification [37,38]. The species is a short-lived herb (up to four years) that can measure from 10 to 50 cm tall; it is an erect to procumbent herb with hairy leaves, dry fruits and presents self-compatible yellow flowers pollinated by hawkmoths in their native distribution [36,39,40]. O. drummondii can be dispersed by barochory, thalassochory and endozoochory [41].…”