Habits general overview

Bromeliads range from small plants even by liliopsid standards to some of the most massive-bodied of the monocots. More comparable among the

Figure 2.4. Shapes of phytotelm (tank-producing) Bromeliaceae. (A D) Four arrangements of foliage that produce phytotelmata of different numbers, exposures and depths per shoot. (E) Aechmea veitchii with virtually no impoundment capacity. (F) Carnivorous Brocchinia reducta. (G) Mature shoot of Aechmea bracteata cut open to expose central dry chamber for ants and several older leaf bases con gured to intercept precipitation and litter. (H) Nidularium burchellii, discolorous foliage arranged in a monolayer. (I) Tillandsia lucida, multilayered shoot. (J) Aechmea brev-icollis, distichous phyllotaxis. (K) Billbergia porteana, tubular shoot. (L) Aechmea brassicoides, central leaf forming dry chamber.

Figure 2.4. Shapes of phytotelm (tank-producing) Bromeliaceae. (A D) Four arrangements of foliage that produce phytotelmata of different numbers, exposures and depths per shoot. (E) Aechmea veitchii with virtually no impoundment capacity. (F) Carnivorous Brocchinia reducta. (G) Mature shoot of Aechmea bracteata cut open to expose central dry chamber for ants and several older leaf bases con gured to intercept precipitation and litter. (H) Nidularium burchellii, discolorous foliage arranged in a monolayer. (I) Tillandsia lucida, multilayered shoot. (J) Aechmea brev-icollis, distichous phyllotaxis. (K) Billbergia porteana, tubular shoot. (L) Aechmea brassicoides, central leaf forming dry chamber.

Habitos Generales

Figure 2.5. Trichomes of Pitcairnioideae. (A D) Goblet-shaped trichome of carnivorous Brocchinia reducta, illustrated in section (A), view from top (B), and labyrinthine outer wall of a distal cell in the hydrated (C) and dry (D) conditions. (E) Fosterella penduliflora, in section. (F) Shield. (G) Brocchinia tatei, in section. (H) Shield. (I) Brocchinia micrantha, shield. (J) In section. (K) Navia glandulosa, glandular trichome from sepal (left) and oral bract (right). (L) Uniserrate trichome from juvenile leaf of Navia sp. (M) Trichome shield of Lindmania serrulata. (N) Uniserrate trichome of Lindmania wurdackii. Parts E, F, L, M, N redrawn from Tomlinson (1969).

Figure 2.5. Trichomes of Pitcairnioideae. (A D) Goblet-shaped trichome of carnivorous Brocchinia reducta, illustrated in section (A), view from top (B), and labyrinthine outer wall of a distal cell in the hydrated (C) and dry (D) conditions. (E) Fosterella penduliflora, in section. (F) Shield. (G) Brocchinia tatei, in section. (H) Shield. (I) Brocchinia micrantha, shield. (J) In section. (K) Navia glandulosa, glandular trichome from sepal (left) and oral bract (right). (L) Uniserrate trichome from juvenile leaf of Navia sp. (M) Trichome shield of Lindmania serrulata. (N) Uniserrate trichome of Lindmania wurdackii. Parts E, F, L, M, N redrawn from Tomlinson (1969).

rhizomatous types are the proportions of the individual ramets, or, for the monocarp, just the seedling shoot because these species never branch (Fig. 2.3). The mature seedling and each of its subsequent ramets weighs from a few grams fresh weight (e.g., neotenic Tillandsia and miniaturized Brocchinia species; Fig. 2.1) to thousands of kilograms for those of the

Figure 2.6. Trichomes of Bromelioideae. (A) Aechmea penduliflora, in section. (B) Shield. (C) Billbergia brasiliensis, in section. (D) Shield. (E) Canistrum sp., in section. (F) Shield. All parts redrawn from Tomlinson (1969).

largest sympodial types. Monocarpic Puya raimondii at maturity exceeds all the other Bromeliaceae in mass and height and probably in the number of years required for its unitary body to achieve owering size (Fig. 14.2C).

The individual bromeliad shoot typically consists of a short stem bearing a few to many, closely placed, alternate, usually spirally arranged, strap-shaped to liform leaves. Just two organs, one leaf and an enlarged pro-phyll, constitute each typically rootless ramet of neotenic Tillandsia usneoides (Figs. 2.1, 2.10E). Hundreds of leaves characterize some of its more caulescent relatives (e.g., monocarpic Puya, Tillandsia araujei). Cryptanthus bromelioides and a number of other members of the same genus bear smaller leaves along the rhizome compared with those at its expanded terminus (Fig. 2.11C,D). Certain Bromelia and similarly stolo-niferous members of many additional bromelioid genera exhibit even stronger dimorphism, as do many Pitcairnioideae (e.g., Pitcairnia; Figs. 2.2C, 2.12B). Slender juvenile leaves appear on the shoot of Neoregelia abendrothae before the broader utriculate organs that can trap litter and water develop (Figs. 2.2D, 9.12). Heterophylly is less pronounced in Tillandsioideae where, nonetheless, it has provoked more speculation about evolutionary mechanisms (Fig. 2.11B; Chapter 9).

Leaf size and proportions, particularly the shape of the base and number per shoot, in uence ecophysiology and accordingly the suitability of spe-ci c substrates and climates for certain bromeliads. Phyllotactic fractions range from 2/5 to 5/13 and probably go higher among the caulescent species

Figure 2.7. Trichomes of Tillandsioideae. (A B) Trichome of Tillandsia ionantha showing con guration of shield when dry (A) and wet (B). (C) Rigid trichome shield of Tillandsia bulbosa, abaxial surface. (D) Trichome shield of Tillandsia crocata. (E) Trichome shield of Tillandsia recurvata. (F) Trichome shield of Tillandsia karwinskyana. (G) Trichome of Catopsis nutans, in section. (H) Shield. (I) Leaf of Tillandsia hildae showing banding attributable to presence of trichomes distinguished by the widths of the shields. Parts D, G, H, redrawn from Tomlinson (1969).

Figure 2.7. Trichomes of Tillandsioideae. (A B) Trichome of Tillandsia ionantha showing con guration of shield when dry (A) and wet (B). (C) Rigid trichome shield of Tillandsia bulbosa, abaxial surface. (D) Trichome shield of Tillandsia crocata. (E) Trichome shield of Tillandsia recurvata. (F) Trichome shield of Tillandsia karwinskyana. (G) Trichome of Catopsis nutans, in section. (H) Shield. (I) Leaf of Tillandsia hildae showing banding attributable to presence of trichomes distinguished by the widths of the shields. Parts D, G, H, redrawn from Tomlinson (1969).

that bear numerous narrow leaves (e.g., Tillandsia funckiana, T. filifolia; Fig. 2.1). However, even the most congested foliage of this type casts little self-shade except where the blades are imbricate. Overlapped leaves along the tiny shoots of caulescent Tillandsia bryoides ex outward most while the plant is fully hydrated (Fig. 2.1). Other exceptional taxa exhibit distichous organization (Dyckia estevesii, T. usneoides,

Figure 2.8. Abaxial leaf surfaces of representative Bromeliaceae; scanning electron micrographs. (A) Aechmea bracteata (X150). (B) Catopsis nutans (X150). (C) Tillandsia tectorum (X100). (D) Pitcairnia macrochlamys (X150). (E) Tillandsia ionantha (X175). (F) Bromelia sp. (X150).
Medicinal Plants

Figure 2.9. Ontogeny of the trichome of Tillandsia usneoides viewed in section (A series) and from top (B series). Redrawn from Billings (1904).

Figure 2.9. Ontogeny of the trichome of Tillandsia usneoides viewed in section (A series) and from top (B series). Redrawn from Billings (1904).

T. recurvata; Fig. 2.2H). Occasionally, patterns shift from spiral to distichous along the same shoot (e.g., T. paleacea), or they approach the ortho-distichous condition (leaves two-ranked in a slight spiral; e.g., T. myosura). Distichous phyllotaxis is more common among seedlings, especially in Tillandsia subgenus Diaphoranthema, where in the adult it denotes juvenil-ization.

Axillary buds occur along the entire length of the typical bromeliad shoot, but few ush and, except for the lateral- owered species, those that do produce the standard one or two reiterative ramets (Fig. 6.14). Some of the longer-stemmed saxicoles (Tillandsia diaguitensis) and certain scrambling Pitcairnia species (Fig. 2.12B) branch less predictably, possibly according to physiological status or some external cue like photoperiod. Pitcairnia riparia branches whenever its stolons encounter obstructions that block forward progress. Replacement meristems routinely activate following oral induction that culminates shoot development with as few as one (Fig. 3.3L) to thousands of owers arrayed on a well-de ned in ores-cence (Figs. 3.2 3.4).

Leaves with armed margins characterize most Bromelioideae, and many Pitcairnioideae, presumably to discourage large herbivores (Figs. 2.12 2.14). The epiphytes usually display weaker mechanical defenses than the terrestrials, which if native to arid soils (e.g., certain Bromelia, Hechtia) invest most heavily in spines. Most bromeliads can replace a lost apical meristem with an axillary bud, but apparently regeneration proceeds slowly enough and predation is sufficiently high in many habitats to justify high

Habitos Generales

Figure 2.10. Plant architecture and leaf anatomy of representative Tillandsioideae. (A) Tillandsia usneoides, leaf cross-section. (B) T. recurvata, leaf cross-section. (C) T setacea, leaf cross-section. (D) T. crocata, leaf cross-section. (E) T. usneoides, shoot. (F) T. usneoides, cross-section leaf vein. (G) T. usneoides, cross-section leaf epidermis. (H) T. recurvata, cross-section leaf epidermis. (I) Catopsis floribunda, leaf cross-section. (J) Tillandsia fasciculata, leaf cross-section. (K) T. fasciculata, stomata. (L) T. duratii illustrating leaves capable of holdfast. (M) T. ionantha var. van-hyningii (saxicole). (N) T. ionantha var. zebrina (epiphyte). Parts AD, FK redrawn from Tomlinson (1969).

Figure 2.10. Plant architecture and leaf anatomy of representative Tillandsioideae. (A) Tillandsia usneoides, leaf cross-section. (B) T. recurvata, leaf cross-section. (C) T setacea, leaf cross-section. (D) T. crocata, leaf cross-section. (E) T. usneoides, shoot. (F) T. usneoides, cross-section leaf vein. (G) T. usneoides, cross-section leaf epidermis. (H) T. recurvata, cross-section leaf epidermis. (I) Catopsis floribunda, leaf cross-section. (J) Tillandsia fasciculata, leaf cross-section. (K) T. fasciculata, stomata. (L) T. duratii illustrating leaves capable of holdfast. (M) T. ionantha var. van-hyningii (saxicole). (N) T. ionantha var. zebrina (epiphyte). Parts AD, FK redrawn from Tomlinson (1969).

Sympodial Branch

Figure 2.11. Asexual propagation and related morphology. (A) Tillandsia flexuosa with immature axillary ramet and additional offshoots on spent in orescence. (B) Grass-like basal ramets produced by many soft-leafed Vriesea species. (C D) Stoloniferous Cryptanthus sp., mature ramet (C) and immature ramet (D). (E) Stoloniferous Nidularium lymanioides growing as a hemiepiphyte.

Figure 2.11. Asexual propagation and related morphology. (A) Tillandsia flexuosa with immature axillary ramet and additional offshoots on spent in orescence. (B) Grass-like basal ramets produced by many soft-leafed Vriesea species. (C D) Stoloniferous Cryptanthus sp., mature ramet (C) and immature ramet (D). (E) Stoloniferous Nidularium lymanioides growing as a hemiepiphyte.

cost to protect the shoot tip. Soft-leafed exceptions include some Cryptanthus species in Bromelioideae and Brocchinia and Fosterella of Pitcairnioideae; according to certain sequences in the chloroplast genome these genera lie beyond the core taxa of their respective subfamilies (Fig. 9.20). Unexpectedly well-defended foliage born by members of some arboreal Bromelioideae (e.g., Aechmea bracteata; Fig. 2.4G) raises the possibility of recent ancestors that rooted on the ground.

Sympodial Bromeliaceae branch at different locations along the parent axis depending on the species (Fig. 6.14). Buds inserted at midstem or

Figure 2.12. Growth habits, rhizome bracts and foliage of certain Pitcairnioideae. (A) Drought-deciduous Pitcairnia heterophylla. (B) Scandent Pitcairnia riparia. (C) Pitcairnia sp. equipped with rhizome bracts lacking armature below green foliage with expanded blades. (D) Pitcairnia sp. bearing short, spiny basal leaves that progressively give way to smooth-margined, broader and longer photosyn-thetic types. (E) Single leaf of nonheterophyllic Pitcairniafeliciana. (F) Swollen leaf bases and bulb-like habit of Puya pusilla.

Figure 2.12. Growth habits, rhizome bracts and foliage of certain Pitcairnioideae. (A) Drought-deciduous Pitcairnia heterophylla. (B) Scandent Pitcairnia riparia. (C) Pitcairnia sp. equipped with rhizome bracts lacking armature below green foliage with expanded blades. (D) Pitcairnia sp. bearing short, spiny basal leaves that progressively give way to smooth-margined, broader and longer photosyn-thetic types. (E) Single leaf of nonheterophyllic Pitcairniafeliciana. (F) Swollen leaf bases and bulb-like habit of Puya pusilla.

somewhat below suffice for most taxa. Two sets of ramets, the rst quite small, grass-like and positioned near the base of parent shoots that themselves are still much less than nal size, characterize numerous Tillandsioideae (e.g., some Vriesea species; Fig. 2.11). Later, after the mother ramet begins to ower, one or two more robust offshoots emerge from as many leaf axils midway along the shoot to just below the in ores-cence. Still other species fail to branch the second time (e.g., Alcantarea

Zingiber Cross Section

Figure 2.13. Aspects of leaves of Bromelioideae. (A) Spiny blade margins of Bromelia balansae. (B) Cross-section of blade of Bromelia balansae half way between apex and base illustrating collapsible adaxial hypodermis, stomata and stellate chlorenchyma. (C) Aechmea magdalenae, abaxial epidermis. (D) Hohenbergia urbanianum, cross-section of blade. (E) Portea petropolitana, section revealing nonvascular ber bundles. (F) Leaf silhouettes illustrating four patterns of anthocyanin development (dark areas) common in Neoregelia and encountered less often in several other genera. Parts B E redrawn from Tomlinson (1969).

Figure 2.13. Aspects of leaves of Bromelioideae. (A) Spiny blade margins of Bromelia balansae. (B) Cross-section of blade of Bromelia balansae half way between apex and base illustrating collapsible adaxial hypodermis, stomata and stellate chlorenchyma. (C) Aechmea magdalenae, abaxial epidermis. (D) Hohenbergia urbanianum, cross-section of blade. (E) Portea petropolitana, section revealing nonvascular ber bundles. (F) Leaf silhouettes illustrating four patterns of anthocyanin development (dark areas) common in Neoregelia and encountered less often in several other genera. Parts B E redrawn from Tomlinson (1969).

imperialis, Puya dasylirioides; Chapter 6), rendering them essentially mono-carpic. Basal ramets in these instances exist primarily to continue the genet should the seedling meristem fail to mature.

Exceptional Tillandsioideae and some Orthophytum augment sympodial branching with offshoots where owers failed to set fruits (Fig. 2.11). Location suggests origin from buds in the axils of oral bracts that for most

Figure 2.14. Aspects of shoots and roots of Bromeliaceae. (A,B) Shoot of Bromelia sp. sectioned and intact illustrating dense masses of trichomes on leaf bases and absence of substantial impoundment capacity. (C) Holdfast roots of Tillandsia edithiae. (D) Abundant apogeotropic roots exposed by removing the leaf bases of caulescent Brocchinia micrantha. (E) Stoloniferous epiphytic Neoregelia sp. (F) Aechmea chantinii illustrating banded distribution of trichomes on abaxial leaf surface. (G) Banded pigmentation marking the leaves of Vriesea fosteriana. (H) Billbergia sp. illustrating irregular spotting on foliage.

Figure 2.14. Aspects of shoots and roots of Bromeliaceae. (A,B) Shoot of Bromelia sp. sectioned and intact illustrating dense masses of trichomes on leaf bases and absence of substantial impoundment capacity. (C) Holdfast roots of Tillandsia edithiae. (D) Abundant apogeotropic roots exposed by removing the leaf bases of caulescent Brocchinia micrantha. (E) Stoloniferous epiphytic Neoregelia sp. (F) Aechmea chantinii illustrating banded distribution of trichomes on abaxial leaf surface. (G) Banded pigmentation marking the leaves of Vriesea fosteriana. (H) Billbergia sp. illustrating irregular spotting on foliage.

species remain dormant unless activated by injury farther up the in ores-cence. Monopodial types progressively die from the rear forward at the same time as the shoot apex adds replacements, including a succession of lateral in orescences (e.g., Tillandsia complanata, some Dyckia, Greigia; Figs. 2.2B, 2.3C). Inspection of certain reputed cases of monopody (e.g., Tillandsia multicaulis) reveals the usual sympodial condition that leaf-like bracts obscure when the replacement meristem arises immediately below the spent apex.

Exceptional sympodial bromeliads representing all three subfamilies spread via axillary stolons up to several meters long that propagate above or below ground depending on the taxon (e.g., Cryptanthus, Pseudananas; Fig. 2.11D). Quite a few Pitcairnia, certain Cryptanthus and many Tillandsia, among others, possess more upright, leafy, caulescent habits (Fig. 2.12). Some of these plants (e.g., Nidularium lymanioides; Fig. 2.11E) scramble through the lower canopy as hemiepiphytes following establishment on the ground, or they germinate in the canopy and then grow from branch to branch (e.g., Pitcairnia riparia; Fig. 2.12B).

Extensive, brous root systems characterize all Bromeliaceae except the most diminutive, dry-growing Tillandsioideae. Less typical for Liliopsida, each organ travels basipetally from its point of origin inside the stem through many nodes before emerging to penetrate adjacent substrates (Fig. 2.15). Mycorrhiza occur sporadically, but few reports identify the fungi and none document a plant bene t (Chapter 5). Sclerotic cortical and stelar parenchyma provide the strength and durability the slow-growing epiphytes and saxicoles require for prolonged suspension. Absorptive capacity probably varies among taxa and within genotypes according to growing conditions, especially the suitability of substrates.

Bromeliad leaves develop from basal meristems much like those of most monocots, but mature organs differ among and within genotypes (e.g., Fig. 2.12). Three types of heterophylly, that probably serve as many different purposes as described below, occur through the family. Several Pitcairnioideae rely on synchronized abscission to coordinate leaf displays with the availability of moisture (Fig. 2.12A), and channeled blades with in ated, tightly clasping bases (ligulate leaves) mark the bromeliads with phytotelm shoots (Fig. 2.4). The nonimpounders appear more grass-like, or their leaves possess prominent midribs (Fig. 2.2F). Petiolate foliage similar to that of some dicots can confuse all but the experienced collector (e.g., several Bromelia and Cryptanthus species; Fig. 2.12). Pronounced succulence distinguishes some taxa (e.g., Dyckia, dry-growing Tillandsia; Figs. 2.10A D, 2.13B), whereas much thinner blades signal accommodation to humid sites (e.g., Catopsis, Ronnbergia; Fig. 2.17A).

Figure 2.15. Root and stem structure characteristic of many members of Bromeliaceae.

Leaf color is exceptionally vivid and varied among the bromeliads, and trichomes often further ornament foliage. Anthocyanins and chlorophylls in many patterns set off the broad, at leaves of numerous Type Four species (e.g., Vriesea fosteriana; Fig. 2.17B). Foliar indumenta range from con uent to sparse and from relatively ne to coarse textured. Alternating bands of densely and sparsely covered leaf surfaces can produce striking displays (e.g., certain Cryptanthus species, Aechmea chantinii; Figs. 2.14F, 2.18C). Importance to leaf moisture and ion and energy exchange vary according to the amount of leaf area these appendages insulate, certain specializations of their living stalk cells and the shape, mobility and other aspects of the shields (Tables 2.1, 9.1).

Tillandsia Leaf Sheath

Figure 2.16. Aspects of the leaves of Pitcairnioideae. (A) Puya raimondii, cross-section of blade half way between base and apex illustrating stomata, trichome and details of the mesophyll. (B) Cross-section of blade of Pitcairnia trianae illustrating presence of a palisade. (C) Cross-section of blade of Pitcairnia pungens showing its undifferentiated chlorenchyma.

Figure 2.16. Aspects of the leaves of Pitcairnioideae. (A) Puya raimondii, cross-section of blade half way between base and apex illustrating stomata, trichome and details of the mesophyll. (B) Cross-section of blade of Pitcairnia trianae illustrating presence of a palisade. (C) Cross-section of blade of Pitcairnia pungens showing its undifferentiated chlorenchyma.

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