Water mediates fertilization in a terrestrial flowering plant.
New Phytol
; 224(3): 1133-1141, 2019 11.
Article
en En
| MEDLINE
| ID: mdl-31032938
ABSTRACT
Water-mediated fertilization is ubiquitous in early land plants. This ancestral mode of fertilization has, however, generally been considered to have been lost during the evolutionary history of terrestrial flowering plants. We investigated reproductive mechanisms in the subtropical ginger Cautleya gracilis (Zingiberaceae), which has two pollen conditions - granular and filiform masses - depending on external conditions. We tested whether rain transformed granular pollen into filiform masses and whether this then promoted pollen-tube growth and fertilization of ovules. Using experimental manipulations in the field we investigated the contribution of water-mediated fertilization to seed production. Rain caused granular pollen to form filiform masses of germinating pollen tubes, which transported sperm to ovules, resulting in fertilization and seed set. Flowers exposed to rain produced significantly more seeds than those protected from the rain, which retained granular pollen. Insect pollination made only a limited contribution to seed set because rainy conditions limited pollinator service. Our results reveal a previously undescribed fertilization mechanism in flowering plants involving water-mediated fertilization stimulated by rain. Water-mediated fertilization is likely to be adaptive in the subtropical monsoon environments in which C. gracilis occurs by ensuring reproductive assurance when persistent rain prevents insect-mediated pollination.
Palabras clave
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Agua
/
Zingiberaceae
/
Fertilización
Tipo de estudio:
Prognostic_studies
Límite:
Animals
Idioma:
En
Revista:
New Phytol
Asunto de la revista:
BOTANICA
Año:
2019
Tipo del documento:
Article
País de afiliación:
China