Biology subjects

Ackerman, J. D.

Publications and source records attributed to Ackerman, J. D..

2 recordsLinked to original sources

bioRxiv2021

Trick or Treat? Pollinator attraction in Vanilla pompona (Orchidaceae)

Natural pollination of species belonging to the pantropical orchid genus Vanilla remains poorly understood. Based on sporadic records, euglossine bees have been observed visiting flowers of Neotropical Vanilla species. Our research aimed at better understanding the pollinator attraction mechanism of the Neotropical species Vanilla pompona, a crop wild relative with valuable traits for vanilla crop improvement programs. Using video footage, we identified floral visitors and examined their behavior. The flowers of V. pompona attracted Eulaema cingulata males, which distinctively displayed two behaviors: floral scent collection and nectar search; with the latter leading to pollen removal. Morphological measurements of floral and visitor traits showed that other Eulaema species may also act as potential pollinators. Additionally, we recorded natural fruit set in three populations and over a period of two years, tested for nectar presence and analyzed floral fragrances through gas chromatography - mass spectrometry. We observed a low natural fruit set (2.42%) and did not detect nectar. Twenty floral volatile compounds were identified, with the dominant compound trans-carvone oxide previously found to attract Eulaema cingulata males. We hypothesize a dual attraction of Eulaema cingulata males to V. pompona flowers, based on floral fragrance reward as the primary long-distance attraction, and food deception for successful pollen removal. Further research confirming this hypothesis is recommended to develop appropriate conservation policies for Vanilla crop wild relatives, which are the primary reserves of this crops genetic variation.

plant biology↗

bioRxiv2019

Identifying Refugia and Barriers to the Spread of A. graminifolia and D. crumenatum in Puerto Rico

Establishment of new populations is contingent on overcoming abiotic and biotic barriers. While this applies to all species, these hurdles are at the forefront of invasion biology where prediction, prevention, eradication, and control strategies depend on an understanding and exploitation of barriers to establishment and spread. Arundina graminifolia and Dendrobium crumenatum are two invasive orchids spreading throughout Puerto Rico. Current records on their distributions across the island are sparse, and their interactions with the surrounding ecosystem are unknown. Through a direct population survey of all known localities, we identified a new, acquired enemy of both orchids: the orchid-specialist weevil, Stethobaris polita. In this study, we used niche modelling to identify suitable habitats for each orchid on the island and map their current distributions and interactions with S. polita, along with their distributions in the most extreme climate scenario in 2050, in order to contextualize projected patterns of establishment on the island. Our findings show that D. crumenatum flourishes in urban environments which also provide refugia from S. polita. In contrast, there is currently no refugia for A. graminifolia from S. polita attack, as it is more sensitive to the same climatic variables as S. polita. Furthermore, projections into the most extreme climate scenario suggests Puerto Rico will be unsuitable for A. graminifolia and S. politas survival, and become less suitable for D. crumenatum, by 2050.

ecology↗