Root Climbers Research Articles

Species composition, diversity, and abundance of lianas in different secondary and primary forests in a subtropical mountainous area, SW China

AbstractThe species composition, diversity, and abundance of lianas were studied in four secondary forests (a 100‐year‐old forest, a middle‐aged forest, and two younger secondary forests), and compared with an undisturbed primary forest in the Ailao Mountains of subtropical SW China. The results showed that the species composition of lianas differed greatly from the secondary forests to the primary forest, which exhibit early and late‐successional species. The abundance of lianas was relatively higher in the two younger and middle‐aged secondary forests than in the old‐growth secondary and primary forests. However, liana species richness was very limited in the four secondary forests as compared to the primary forest. Root climbers mainly grew in the primary forest, whereas tendril and hook climbers predominated in the four secondary forests, while stem twiners were common in both. The majority of lianas recorded in this study reproduced by animal dispersal, and there was no variation in dispersal modes across the five forest types. A step‐wise regression showed that the abundance of small lianas (dbh <4 cm) was positively correlated with the abundance of small‐ and medium‐sized tree stems and negatively correlated with the abundance of large‐sized tree stems, whereas there is a strong positive correlation between the abundance of large lianas (dbh ≥4 cm) and large tree stems. Results from the CCA indicate that canopy openness, soil moisture, and average canopy height were the most important factors that influenced the abundance and distribution of lianas.

Climbing strategies determine light availability for both vines and associated structural hosts

This study investigated biomass allocation traits and shading impact of vines (ground-rooted climbing plants) on their hosts in a tall open forest understorey community (Blue Gum High Forest) in Sydney, Australia. Eighty-six vine individuals from 11 species (7 natives and 4 exotics) were recorded and sampled on 26 individuals from 5 host species. All host species sampled were <3 m in height. Each recorded climber was assigned to one of the five established climbing strategies: tendril climber, petiole climber, stem twiner, scrambler or root climber. No root climbers were recorded. Each species was also recorded as native or exotic. We measured shading effects of the different climbing strategies by removing vines from their hosts and measuring the change in canopy openness (diffuse non-interceptance, DIFN) above the host. Vines had significantly greater specific leaf area than their hosts. The most abundant climbing strategy was stem twining, followed by scrambling, petiole twining and tendril climbing. Leaf mass fraction (leaf mass per total aboveground biomass) did not differ among climbing strategies or between natives and exotics. Vines reached taller heights on taller hosts and the percentage of host’s shoot height reached differed significantly among climbing strategies: petiole twiners and scramblers reached the largest percentage host shoot height (97% and 92%, respectively) whereas stem twiners and tendril climbers reached 68% and 61%, respectively. Total relative shading of the host increased significantly with increasing vine biomass. There were significant differences between climbing strategies in the shading imposed on hosts. In the context of average canopy openness above the understorey for this site (24%), scramblers reduced light availability to their hosts by nearly 25%, compared with petiole-tendril twiners (14%) and stem twiners (8%). Thus, climbing strategies differentially shape the light environment available to their structural hosts.

An Early Cretaceous root-climbing epiphyte (Lindsaeaceae) and its significance for calibrating the diversification of polypodiaceous ferns

The discovery of fossilised roots of a lindsaeoid fern within the trunk of the extinct tree fern Tempskya provides new fossil evidence for Lindsaeaceae in the Mesozic, as well as the first direct evidence of an ecological association between Tempskya and root-climbing epiphytes. Data were collected from permineralised Tempskya trunks from the Aspen Shale (Early Cretaceous, Albian), Wyoming (USA). The roots of the lindsaeoid fossil are clearly distinguishable from those of Tempskya and other living ferns based on a suite of distinctive anatomical features, which are described in detail. The foliage is unknown. The new fossil is interpreted as a root climber, and comparisons are made with similar living species in Lindsaea subgenus Odontoloma (Lindsaeaceae). The documentation of Lindsaeaceae in the Early Cretaceous adds to a small but growing body of data on the diversification of polypodiaceous ferns during this important period. These recent discoveries point to a much earlier (Early Cretaceous) crown group radiation of polypodiaceous ferns than previously suspected.

Evolution of growth form in epiphytic Dissochaeteae (Melastomataceae)

Abstract We trace the evolution of root climbing and scrambling in Dissochaeteae and Sonerileae, two closely related groups that comprise the majority of Old World climbing Melastomataceae. The morphological and anatomical adaptations of the different climbers are interpreted in the context of a phylogeny based on chloroplast (cp) DNA sequences of the ndhF gene, generated for 31 representatives of Dissochaeteae and Sonerileae/Oxysporeae plus nine outgroups. For 20 of these taxa, the ndhF sequences were combined with cpDNA rpl16 intron sequences to obtain higher statistical support. Parsimony, minimum evolution, and maximum likelihood approaches yield congruent topologies that imply that scrambling growth evolved once in the common ancestor of Dissochaetinae, a group of ∼40 species centered around Dissochaeta and its close relatives Macrolenes and Diplectria. Root climbing, on the other hand, likely evolved in the common ancestor of Catanthera, Kendrickia, and Medinilla section Heteroblemma (together 26 species). In Melastomataceae overall, scrambling is restricted to Dissochaetinae, while root climbing has evolved several times. The scramblers are diverse in open disturbed habitats and show adaptations such as sarmentose branches, hook-shaped adventitious roots, and interpetiolar outgrowths that enhance their ability to lean on and clamber over other plants. Root climbers in the Catanthera- Kendrickia- Heteroblemma clade are restricted to humid habitats and show adaptations such as anomalous growth of the secondary xylem (a rare feature in the family), living climbing roots, and pseudoalternate phyllotaxy, which allows optimal arrangement of the normally opposite melastome leaves against the host's trunk.

Alpha diversity of lianas in a tropical evergreen forest in the Anamalais, Western Ghats, India

Abstract. Species richness, abundance, size‐class distribution, climbing mode and spatial patterns of lianas were investigated in a 30‐ha permanent plot of tropical evergreen forest at Varagalaiar in the Anamalais, Western Ghats, India. Each hectare was subdivided into 10 m × 10 m quadrats, in which all lianas ≥ 1 cm d.b.h. were measured, tagged and identified. The total liana density was 11, 200 individuals (373 ha–1) and species richness was 75 species, representing 66 genera and 37 families. The richness estimators employed for species and family accumulation curves after 100 times randomization of sample order, have stabilized the curves at 16th and 15th hectares, respectively. A greater proportion of lianas was twiners (55% of species and 44.4% of density) and root climbers (5% of species and 14% of density), and a few were tendril climbers, reflecting the late successional stage of the forest. In the size‐class distribution, 82% of abundance and 97% of species richness fell within 1–3 cm diameter threshold. The dominance of succulent diaspore type signifies the faunal dependence of lianas on vertebrate frugivores for dispersal. The diversity, population density and family composition of lianas of our site is compared with those of other tropical forests. The need for biomonitoring of this synusia in the permanent plot for forest functioning is emphasized.

How Trees Avoid and Shed Lianas

How Trees Avoid and Shed Lianas

Growth Relationships of Leaves and Internodes in Viny Angiosperms with Different Modes of Attachment

The timing of leaf expansion in relation to the elongation of adjacent internodes was compared in 37 species of vines which climb by means of twining stems, tendrils, or roots. Interspecific comparisons were made with a growth index, L, defined as the fraction of the final length of a leaf when an adjacent internode reached 75 % of its final length. The index was calculated for both of the leaf positions adjacent to an internode: La for the leaf above the internode, Lb for the leaf below the internode. The value of L was low in many twiners and tendril climbers (La, Lb < 0.33 in 15 of 29 species). Four twiners formed scale leaves (La and Lb = 1.0) and in two climbers with leaf tip tendrills (Pisum, Gloriosa) the maturation of leaves was not delayed (La = 0.73, 0.94 respectively). In all five species (5/5) of monocotyledonous root climbers a leaf completed elongation together with, or before, one of the adjacent internodes. In 2/3 species of dicotyledonous root climbers the elongation of leaves was delayed in relation to both adjacent internodes, but the value of La was greater than in most twiners. The timing of adjacent internode elongation was evaluated using a second index, T, defined as the fraction of final length of an internode when the subjacent internode reached 75 % of its final length. Wide-ranging extremes were found among various species, from 0.70 in Asparagus to 0.05 in Anthurium. Root climbers exhibited generally lower T values than twiners or tendril climbers. These results are in agreement with the concept of earlier qualitative studies that the pattern of leaf and internode development in vines is related to their mode of attachment. Delayed leaf expansion has been considered important in the biology of twining and tendril climbing vines because large foliage leaves are thought to decrease the effectiveness of shoots “searching” for a support. The present study provides the first quantitative, comparative description of the timing of leaf growth in vines. The leaves of non-vines commonly mature together with, or before, the adjacent internodes.

GROWTH RELATIONSHIPS OF LEAVES AND INTERNODES IN VINY ANGIOSPERMS WITH DIFFERENT MODES OF ATTACHMENT

The timing of leaf expansion in relation to the elongation of adjacent internodes was compared in 37 species of vines which climb by means of twining stems, tendrils, or roots. Interspecific comparisons were made with a growth index, L, defined as the fraction of the final length of a leaf when an adjacent internode reached 75 % of its final length. The index was calculated for both of the leaf positions adjacent to an internode: La for the leaf above the internode, Lb for the leaf below the internode. The value of L was low in many twiners and tendril climbers (La, Lb &lt; 0.33 in 15 of 29 species). Four twiners formed scale leaves (La and Lb = 1.0) and in two climbers with leaf tip tendrills (Pisum, Gloriosa) the maturation of leaves was not delayed (La = 0.73, 0.94 respectively). In all five species (5/5) of monocotyledonous root climbers a leaf completed elongation together with, or before, one of the adjacent internodes. In 2/3 species of dicotyledonous root climbers the elongation of leaves was delayed in relation to both adjacent internodes, but the value of La was greater than in most twiners. The timing of adjacent internode elongation was evaluated using a second index, T, defined as the fraction of final length of an internode when the subjacent internode reached 75 % of its final length. Wide‐ranging extremes were found among various species, from 0.70 in Asparagus to 0.05 in Anthurium. Root climbers exhibited generally lower T values than twiners or tendril climbers. These results are in agreement with the concept of earlier qualitative studies that the pattern of leaf and internode development in vines is related to their mode of attachment. Delayed leaf expansion has been considered important in the biology of twining and tendril climbing vines because large foliage leaves are thought to decrease the effectiveness of shoots “searching” for a support. The present study provides the first quantitative, comparative description of the timing of leaf growth in vines. The leaves of non‐vines commonly mature together with, or before, the adjacent internodes.

Biological Films

THE Gaumont British Instructional Films Bureau has recently added some interesting biological films to its already extensive collection. “Climbing Plants” portrays clearly the many different devices for climbing adopted by plants in their struggle for existence, including 'scramblers', thorn, petiole and aerial root climbers, as well as types that climb by means of tendrils and stems. The photographs of circumnutation in the bean seedling are as excellent as the rest of the film. In “The Swan”, the photographer has captured some entertaining 'shots' of the famous swannery at Abbotsbury, near Wey-mouth. Courtship and breeding are carefully presented, as well as pleasant recordings of cygnet development. “The Life-Story of a Fern” includes photographs of royal, hart's-tongue, male and bracken ferns, indicating methods of spore production and liberation. In this film some informative pictures of fertilization processes in the ferns are particularly noteworthy.