| Full text | |
| Author(s): |
Total Authors: 3
|
| Affiliation: | [1] Univ Sao Paulo, Inst Biosci, BR-05508090 Sao Paulo - Brazil
[2] Harvard Univ Herbaria, Cambridge, MA 02138 - USA
Total Affiliations: 2
|
| Document type: | Journal article |
| Source: | AMERICAN JOURNAL OF BOTANY; v. 108, n. 5, p. 756-768, MAY 2021. |
| Web of Science Citations: | 1 |
| Abstract | |
Premise A subset of parasitic plants bear extremely reduced features and grow nearly entirely within their hosts. Until recently, most of these endoparasites were thought to represent a single clade united by their reduced morphology. Current phylogenetic understanding contradicts this assumption and indicates these plants represent distantly related clades, thus offering an opportunity to examine convergence among plants with this life history. Methods We sampled species from Apodanthaceae, Cytinaceae, Mitrastemonaceae, and Rafflesiaceae spanning a range of developmental stages. To provide a broader comparative framework, Santalaceae mistletoes with a similar lifestyle were also analyzed. Microtomography and microscopy were used to analyze growth patterns and the ontogeny of host-parasite vascular connections. Results Apodanthaceae, Cytinaceae, Mitrastemonaceae, and Rafflesiaceae species demonstrated a common development characterized by late cell differentiation. These species were also observed to form direct connections to host vessels and to cause severe alterations of host xylem development. Apodanthaceae and Rafflesiaceae species were additionally observed to form sieve elements, which connect with the host phloem. Endophytic Santalaceae species demonstrated a dramatically different developmental pattern, featuring early cell differentiation and tissue organization, and little effect on host anatomy and cambial activity. Conclusions Our results illuminate two distinct developmental trajectories in endoparasites. One involves the retention of embryonic characteristics and late connection with host vessels, as demonstrated in species of Apodanthaceae, Cytinaceae, Mitrastemonaceae, and Rafflesiaceae. The second involves tissue specialization and early connection with host xylem, as exemplified by Santalaceae species. These differences are hypothesized to be related to the absence/presence of photosynthesis in these plants. (AU) | |
| FAPESP's process: | 13/23322-3 - Phenolic compounds, carbohidrates and lipids in the parasitic interaction of Tapirira guianensis (Anacardiaceae)and Phoradendron crassifolium (Santalaceae) |
| Grantee: | Fernanda Anselmo Moreira |
| Support Opportunities: | Scholarships in Brazil - Master |