Root hair anatomy and morphology in Posidonia oceanica (L.) Delile and substratum typology: First observations of a spiral form

Tomasello, Agostino; Perrone, Rosaria; Colombo, P.C.; Pirrotta, Maria; Calvo, Sebastiano

doi:10.1016/j.aquabot.2017.12.001

Cited by 16 publications

(11 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, the root hairs seemed to use different anchorage strategies depending on the substrata type. In agreement with the results of other studies [ 31 , 58 ], the adhesive root hairs of the seedlings grown in pebbles adhered through their edges to the substrate and formed a kind of adhesive buttons, even when pebbles were mixed with sand. However, when the substrata were only sand or fibreglass, the root hairs did not show these adhesive buttons but embraced substrate particles instead.…”

Section: Discussionsupporting

confidence: 92%

“…oceanica and Thalassia testudinum [ 27 , 67 ], but the fruits and seeds of the other species of these genera display a bright green colour on the surface, which indicates high levels of chloroplasts [ 48 , 62 , 68 , 69 ]. These three seagrass genera also form microscopic adhesive root hairs that enhance the anchorage of the seeds and the primary root system to substrata [ 31 , 48 , 58 , 70 ]. These seagrass genera also share a similar life history strategy by forming persistent extensive meadows with sporadic sexual reproduction [ 25 ].…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Understanding the sexual recruitment of one of the oldest and largest organisms on Earth, the seagrass Posidonia oceanica

2018

View full text Add to dashboard Cite

The seagrass Posidonia oceanica is considered one of the oldest and largest living organisms on Earth. Notwithstanding, given the difficulty of monitoring its fruits and seeds in the field, the development of P. oceanica during its sexual recruitment is not completely understood. We studied the stages of development of P. oceanica seeds from their dispersion in the fruit interior to their settlement in sediment through histological, ultrastructural and mesocosm experiments. P. oceanica sexual recruitment can be divided into three main stages that focus on maximising photosynthesis and anchoring the seedlings to the sediment. In the first stage (fruit dispersion), seeds perform photosynthesis while being transported inside the fruit along the sea surface. In the second stage (seed adhesion), seeds develop adhesive microscopic hairs that cover the primary and secondary roots and favour seed adhesion to the substrate. In the last stage (seedling anchorage), roots attach the seedlings to the substrate by orienting them towards the direction of light to maximise photosynthesis. The adaptations observed in P. oceanica are similar to those in other seagrasses with non-dormant seeds and fruits with membranous pericarps, such as Thalassia sp. and Enhalus sp. These common strategies suggest a convergent evolution in such seagrasses in terms of sexual recruitment. Understanding the sexual recruitment of habitat-forming species such as seagrasses is necessary to adequately manage the ecosystems that they inhabit.

show abstract

Section: Discussionsupporting

confidence: 92%

Section: Discussionmentioning

confidence: 99%

Understanding the sexual recruitment of one of the oldest and largest organisms on Earth, the seagrass Posidonia oceanica

2018

View full text Add to dashboard Cite

show abstract

“…Our analysis of the morphology and ultrastructure of P. oceanica seedlings showed a unique pad formation process characterized by the root hair tip branching behavior and by the presence of a solidifying (filler) substance at the substrate/ pad interface. These two features, reported here for the first time, together with the presented numerical model simulations allow for better understanding of the adhesion mechanism of P. oceanica described in previous works (Alagna et al, 2015;Badalamenti et al, 2015;Tomasello et al, 2018;Zenone et al, 2020). The numerical model simulated the contact formation of the P. oceanica seedling root hair on hard rough substrates, clarifying what role the physical properties of the root hairs play in pad formation and in the facilitation of the attachment process.…”

Section: Discussionsupporting

confidence: 71%

“…However, similar anchorage systems have been described in some terrestrial climbing plants [eg, Ficus pumila (Groot et al, 2003), Parthenocissus tricuspidata (Scherge and Gorb, 2001;Steinbrecher et al, 2010;Steinbrecher et al, 2011), Hedera helix (Melzer et al, 2010, Amphilophium crucigerum (Seidelmann et al, 2012), Passiflora discophora (Bohn et al, 2015), and Syngonium podophyllum (Yang and Deng, 2017)]. To the best of our knowledge, no similar detailed studies exist for most seagrass species, even though the morphology and ultrastructure of root hair have been described for some of them (Cooper and McRoy, 1988;Roberts, 1993;Tomasello et al, 2018).…”

Section: Discussionmentioning

confidence: 94%

Root Hair Adhesion in Posidonia oceanica (L.) Delile Seedlings: A Numerical Modelling Approach

Zenone¹,

Filippov²,

Kovalev³

et al. 2020

Front. Mech. Eng.

View full text Add to dashboard Cite

Animals and plants use adhesion to move, to anchor to a substrate, or to disperse seeds and fruits. Some plants developed a root pad as a common strategy to adhere to consolidated substrates. In the marine environment, the seagrass Posidonia oceanica attaches firmly to consolidated substrates via adhesive root hairs, forming a pad structure. We used novel morphological and ultrastructural data to develop a numerical model to study the dynamics of root hair adhesion during contact formation on rough consolidated substrates for this species. Morphological analysis, conducted using Scanning Electron Microscope, highlighted the role of root hair branching in pad formation. Transmission Electron Microscope microscopy allowed us to identify a glue-like substance at the pad/ substrate interface. The numerical model highlighted the role played by the cell wall's elasticity in pad formation and its importance in guaranteeing a firm adhesion. Furthermore, the effectiveness of these mechanisms was assessed at different simulated roughness levels. Increasing knowledge on the adhesion mechanism of seagrass to consolidated substrates could be pivotal in developing advanced seedling-based restoration protocols. The findings of this study could contribute to restoration activities planned to contrast seagrass regression. Transplanting initiatives using seedlings can now better address the search for suitable and low-impact ways to fix germinated plants to the substrate.

show abstract

“…In addition to the apical swellings, P. oceanica root hairs are strengthened by spirally formed cells walls 30 , [this study], a feature recently reported also by Tomasello et al . 60 . These authors recognized two types of root hairs in P. oceanica growing in NW Sicily (Italy), i.e., “tubular” and “spiral-shaped”, where the latter is morphologically identical to the elongated root hairs probably damaged by too high breaking force as reported here and in Vohník et al .…”

Section: Discussionmentioning

confidence: 99%

Ontogenetic transition from specialized root hairs to specific root-fungus symbiosis in the dominant Mediterranean seagrass Posidonia oceanica

Borovec

Vohník

2018

Sci Rep

View full text Add to dashboard Cite

Terrestrial plants typically take up nutrients through roots or mycorrhizae while freshwater plants additionally utilize leaves. Their nutrient uptake may be enhanced by root hairs whose occurrence is often negatively correlated with mycorrhizal colonization. Seagrasses utilize both leaves and roots and often form root hairs, but seem to be devoid of mycorrhizae. The Mediterranean seagrass Posidonia oceanica is an exception: its adults commonly lack root hairs and regularly form a specific association with a single pleosporalean fungus. Here we show that at two sites in the southern Adriatic, all its seedlings possessed abundant root hairs with peculiar morphology (swollen terminal parts) and anatomy (spirally formed cell walls) as apparent adaptations for better attachment to the substrate and increase of breaking strain. Later on, their roots became colonized by dark septate mycelium while root hairs were reduced. In adults, most of terminal fine roots possessed the specific fungal association while root hairs were absent. These observations indicate for the first time that processes regulating transition from root hairs to root fungal colonization exist also in some seagrasses. This ontogenetic shift in root traits may suggests an involvement of the specific root symbiosis in the nutrient uptake by the dominant Mediterranean seagrass.

show abstract

Root hair anatomy and morphology in Posidonia oceanica (L.) Delile and substratum typology: First observations of a spiral form

Cited by 16 publications

References 17 publications

Understanding the sexual recruitment of one of the oldest and largest organisms on Earth, the seagrass Posidonia oceanica

Understanding the sexual recruitment of one of the oldest and largest organisms on Earth, the seagrass Posidonia oceanica

Root Hair Adhesion in Posidonia oceanica (L.) Delile Seedlings: A Numerical Modelling Approach

Ontogenetic transition from specialized root hairs to specific root-fungus symbiosis in the dominant Mediterranean seagrass Posidonia oceanica

Contact Info

Product

Resources

About