Floral Scent Evolution in the Genus Jaborosa (Solanaceae): Influence of Ecological and Environmental Factors

MORÉ, MARCELA; SOTERAS, FLORENCIA; IBAÑEZ, ANA C.; DÖTTERL, STEFAN; COCUCCI, ANDREA A.; RAGUSO, ROBERT A.

Plants

MDPI

Lugar: Basilea; Año: 2021 vol. 10

Floralscent is a key communication channel between plants and pollinators.However, the contributions of environment and phylogeny to floralscent composition remain poorly understood. In this study, wecharacterized interspecific variation of floral scent composition inthe genus Jaborosa Juss. (Solanaceae) and, using an ecological nichemodelling approach (ENM), we assessed the environmental variablesthat exerted the strongest influence on floral scent variation,taking into account pollination mode and phylogenetic relationships.Our results indicate that two major evolutionary themes have emerged:(i) a ?warm Lowland Subtropical nectar-rewarding clade? withlarge white hawkmoth pollinated flowers that emit fragrancesdominated by oxygenated aromatic or sesquiterpenoid volatiles, and(ii) a ?cool-temperate brood-deceptive clade? of largelyfly-pollinated species found at high altitudes (Andes) or latitudes(Patagonian Steppe) that emit foul odors including cresol, indole andsulfuric volatiles. The joint consideration of floral scent profiles,pollination mode, and geoclimatic context helped us to disentanglethe factors that shaped floral scent evolution across ?pollinatorclimates? (geographic differences in pollinator abundance orpreference). Our findings suggest that the ability of plants in thegenus Jaborosa to colonize newly formed habitats during Andeanorogeny was associated with striking transitions in flower scentcomposition that trigger specific odor-driven behaviors in nocturnalhawkmoths and saprophilous fly pollinators.p { margin-bottom: 0.1in; line-height: 115%; background: transparent }