BROMELI ANA PUBLISHED by the NEW YORK BROMELIAD SOCIETY (Visit Our Website
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BROMELI ANA PUBLISHED BY THE NEW YORK BROMELIAD SOCIETY (visit our website www.nybromeliadsociety.org) May, 2013 Volume 50, No. 5 OUR PLANT FAMILY Bromeliaceae by Herb Plever At recent meetings I have noticed that many from Harry Luther’s 2012 Bromeliad Binomials. It members have only a vague idea of how the reflects novel revisions from previous classifications Bromeliad Family with its more than 3,200 species is in the last decade made by evolutionary biologists organized. Understandably, they are concentrating on from molecular DNA research on the Bromeliad the challenge to grow plants that come from family. (We will see further changes in the near (sub)tropical or dessert, low or high altitude, hot or future. Genus Aechmea, for one, has messy cold, dry or wet environments in their indoor contradictions and likely will be revised. Also, the apartments or homes. relationship between species of Tillandsia and Moreover, many once popular species are not Vriesea needs to be clarified.) well known today and are hard to find because of the explosion of attractive hybrid cultivars that has BROCHINIOIDEAE swamped the bromeliad world. We do need Brocchinia - 20 discussion and information about horticultural techniques (about which very little is written), but a LINDMANIOIDEAE basic understanding of the family is also essential for Connellia - 6 a grower’s education. Lindmania - 9 Family Bromeliaceae (bro-meel-ee-ay-see-ee) HECHTIOIDEAE is a part of the flowering plants (angiosperms) sub- Hechtia - 62 division of the Plant Kingdom. All of its species are NAVIOIDEAE monocotyledons (monocots), that is to say that each Brewcaria - 6 Sequencia - 1 seed initially has only one leaf. Dicots have two seed Cottendorfia - 1 Steyerbromelia - 6 leaves. Until about 4 years ago the family was divided Navia -93 into three sub-families: Pitcairnioideae, Tillandsioideae and Bromelioideae. Now PITCAIRNIOIDEAE taxonomists have converted former sub-family Deuterocohnia -18 Fosterella - 31 Pitcairnioideae into 6 new sub-families: Dyckia -147 Pepinia -57 Brochinioideae, Lindmanioideae, Hechtioideae, Encholirium - 28 Pitcairnia -342 Navioideae, Pitcairnioideae and Puyoideae. The following is the new list of the sub- PUYOIDEAE families and their genera with the number of species Puya - 218 NEXT MEETING - Tuesday, May 7th , 2013 promptly at 7:00 P.M. at the Ripley-Grier Studios 520 8th Ave. (between 36th & 37th St) Room 17A THE PLANTS YOU ORDERED - We’ll display each plant that was ordered and will discuss potential problems and where and how to grow them. IDENTIFICATION FOR DUMMIES - A simple exposition of how to discern key characters to identify a plant. Please bring in plants for sale and for Show and Tell. Reminder: you must pick up the plants you ordered at this meeting! Bromeliana -2- May, 2013 TILLANDSIOIDEAE (9 genera) BROMELIOIDEAE CONT’ Alcantarea -32 Racinaea -74 Deincanthon -1- Neoglaziovia - 3 Catopsis - 18 Tillandsia - 622 Disteganthus - 2 Neoregelia - 120 Glomeropitcairnia -2 Vriesea - 281 Edmundoa - 3 Nidularium - 47 Guzmania - 211 Werauhia - 88 Eduandrea - 1 xNiduregelia - 3 Mezobromelia - 9 Fascicularia - 1 Ochagavia - 4 Fernseea -2 Orthophytum - 68 BROMELIOIDEAE (35 genera) Greigia - 36 Portea - 9 Acanthostachys - 2 Billbergia - 63 Hohenbergia - 65 Pseudoaechmea - 1 Aechmea - 276 Bromelia - 60 Hohenbergiopsis - 1 Pseudoananas - 1 Ananas - 7 Canistropsis - 11 xHohenmea - 1 Quesnelia - 23 Androlepis -2 Canistrum - 13 Laptanthus - 2 Ronnbergia - 14 Araeococcus -9 Cryptanthus - 72 Lymania - 9 Ursulaea - 2 Wittrockia - 6 PHOTOSYNTHESIS Part 3 Conclusion by Don Beard (Excerpted from Far North County Bromeliad Study Group, New South Wales, Aust. Newsletter, April 2012) ...In this article the CAM photosynthetic pathway is dark and no photosynthesis can occur without and CAM plants are discussed. CAM is an acronym sunlight)...At dawn the stomata close, the malic acid for Crassulacean Acid Metabolism, meaning the type moves from the vacuoles, is converted to malate and of acid metabolism found in the Crassulaceae, a family is decarboxylated (removal of a carboxyl group and of succulent plants. It was developed as an adaptation release of carbon dioxide) in the chloroplasts into CO2 to arid conditions. Briefly the CAM pathway involves and PEP (Phosphoenolpyruvic acid)...The water the plant shutting stomata (pores) during the day to efficiency of this process is demonstrated by the fact reduce water loss, opening them at night to collect that C3 plants lose 97% of their water by transpiration CO2, and storing the CO2 as the 4C molecule malic whereas CAM plants loose little to none. All this is acid. Then the next day with the stomata shut, CO2 is achieved by just shutting the stomata during the day. reproduced and used for photosynthesis. The malic CAM Plants and Their Characteristics acid gives the leaf of the CAM plant a bitter/acid taste Of the vascular plant species, some 7% or during the night which disappears during the day. 15,000-20,000 species, 300 genera, and 40 families are Examples of CAM plants include bromeliads, orchids, CAM plants (this is considered an underestimate). As cacti and Jade plants...Most are epiphytes or stated previously the majority of CAM plants are succulents. either epiphytes or succulents, although just about Mechanism - CAM probably developed as a two part every other growing environment is represented. Most (day/night) 24 hour cycle as an adaptation to increased are angiosperms (flowering plants), and CAM species water efficiency. At night during lower temperatures are five times more numerous than C4 species. the stomata open and There are a number of factors which influence atmospheric CO2 enters the degree of CAM photosynthetic pathway, and these Bromeloideae 91% and is fixed in the include salinity; pollutants, these decrease the Puya 24% spongy mesophyll cells nocturnal CO2 uptake; nutrient availability; increased Dyckia and relatives 100% by an enzyme reaction CO2, which increases the malate; the light level; Hectia 100% (PEPC) forming HCO3. oxygen; air vapour pressure; temperature; water stress, Tillandsioideae 28% Malate is produced which influences the enzyme type and volume; nearly all the which synthesises malic nitrogen etc. CAM plants often show xerophytic atmospherics acid to be stored in the characters which include; thickened and reduced cell’s vacuole leaves, which have a low surface to volume ratio; over-night (remember it thickened cuticles; sunken stomata; trichomes; and Bromeliana -3- May, 2013 the photosynthetic process is protected from CO2 and enhanced by drought. A couple of interesting points water stresses; few other plants can survive such regarding CAM broms, are that water on the leaves extended neglect….my kind of plant. The following appears to prevent the uptake of CO2 because the characteristics belong to all CAM plants: CAM plants trichomes become bloated and flattened and block the can separate the photosynthetic light and dark stomata. Also the leaves contain a pigment called processes. Large vacuoles; reduced intercellular zeaxanthin that prevents photo-damage (sunburn) to air-space; increased cell size. the photosynthesis apparatus. Because the CAM primary driver is the frugal Evolution CAM has evolved convergently many use of water, CAM plants have meagre photosynthetic times i.e. the same biological trait is the end result in rates, and hence suffer a yield (growth) penalty. CAM different or unrelated lineages. In the Bromeliaceae it plants need more energy to fix CO2 than C3 or C4 has evolved at least four times in response to climatic plants. C4 plants have the highest growth rate of all and geologic changes since the late Tertiary ( 2.5 land plants, whereas CAM plants are amongst the million years). Within the subfamily Tillandsioideae slowest growing on earth. C3 plants grow C3 is plesiomorphic (ancestral) and CAM has predominantly at night, but CAM plants maximum developed later in most extreme epiphytes. In the growth rate is in the middle of the day. Net CO2 subfamily Bromelioideae CAM predates epiphytism exchange is inhibited by surface wetting. This is a clue with subsequent radiation into less xeric habitats and on when not to water your CAM broms, since with reversion to C3 in some taxa. Thus we have exchange occurs at night. The more the stress the gained and lost CAM in evolutionary history. The higher the usage of CO2 recycling, so that the evolutionary trend, terrestrial to epiphytic is closely photosynthetic process is little affected by linked to the elaboration of absorptive epidermal drought.CAM plants fix CO2 15% more efficiently trichomes that are characteristic of the family. than C3 plants but 10% less efficiently than C4 plants. CAM broms come in all shapes and sizes, i.e. Bromeliaceae - they are extremely diversified, from soil rooted 69% of the Bromeliaceae are CAM plants or terrestrials to rosulate tank broms which impound both CAMC3 (meaning depending on the conditions can water and nutrients, to rootless extreme epiphytes convert to either). Obviously then, 31% are C3 plants. which are independent of the substrate. To sort out a There are no C4 plants in this family. The table more precise evolution of CAM within the highlights which broms are CAM within the family. Bromeliaceae one needs a robust phylogeny There may well be some alterations/additions to this (evolution) for the family based on molecular (genetic) list as time passes, however because of the fairly clear and morphological characteristics, something which determination process of whether a plant is C3 or needs more work and is unavailable at present. CAM, they are unlikely to be numerous. Note that the Consequently many taxonomic relationships remain Orchidaceae has more CAM species than any other controversial. plant family. As a generalization, those bromeliads Since it is not possible to assign precise which are atmospheric Tillandsias, or tank bromeliads chronology to the family’s history it is equally with trichomes and stiff leaves are CAM plants. C3 impossible to construct the history for CAM in the plants have softer leaves and live in shaded and less Bromeliaceae.