Abstract Detail

Ecophysiology

Rodriguez, Arantza [1], Castillo, Raul [2], Collazo-Ortega, Margarita [1].

Inbreeding reduces seed germination of the Neotropical riverweed Marathrum foeniculaceum (Podostemaceae).

Inbreeding, the preferential breeding between close relatives frequently reduces genotypic variation of individuals between populations and increases the expression of recessive deleterious alleles. It is expected that inbreeding constrains the ability of plants to respond to environmental factors at different stages of the plant’s life history, reducing plant fitness (i. e., inbreeding depression). Seed germination is one of the most important stages in a plants life cycle, which is expected to be affected by inbreeding. However, empirical evidence supporting this notion is mixed and is still scarce for aquatic plants. Unlike other aquatic plants, for riverweeds (Podostemaceae) sexual reproduction is the primary mode of reproduction. Thus, seed germination is a fundamental process for these riverweeds as it drives species distribution, survival, and abundance. In this context we evaluated the effect of inbreeding on seed germination of the neotropical podostemad Marathrum foeniculaceum. To do so, we performed experimental crosses at two natural populations in rivers of Puerto Vallarta, Mexico, in order to obtain fruits derived from three pollination treatments (natural pollination N = 14, selfing N = 5 and outcrossing N = 3). Resulting seeds were used in a controlled environment camera experiment that included a light quality treatment (white vs. red). Under white light conditions final germination percentage resulted significantly lower in the selfing treatment (30%) compared to natural pollination (88.5%) and outcrossing (93%), which did not differ from each other. Similarly, under red light conditions, final germination percentage resulted significantly lower in the selfing treatment (38.5%) compared to natural pollination (87.5%) and outcrossing (89.7%), which did not differ from each other. These results suggest that inbreeding can reduce importantly seed germination of riverweeds. It is essential to conserve natural habitats of Podostemaceae in order to avoid low populations densities that can promote inbreeding and its negative effects on seed germination in natural populations of this particular group of aquatic plants.

1 - Universidad Nacional Autónoma de México, Comparative Biology, Ciudad Universitaria, Alcaldía Coyoacán, México, México, 03100, México
2 - Universidad Autónoma de Baja California, Facultad de enología y gastronomía, Carretera transpeninsular Ensenada-Tijuana, Col. del Valle, Ensenada, Baja California, 22860, México

Keywords:
Inbreeding
Podostemaceae
Riverweeds
reproduction.

Presentation Type: Poster
Session: P, Ecophysiology Posters
Location: Virtual/Virtual
Date: Tuesday, July 28th, 2020
Time: 5:00 PM Time and date to be determined
Number: PPE003
Abstract ID:354
Candidate for Awards:Physiological Section Physiological Section Li-COR Prize