The Orchid Garden

What is an orchid?

Question:

Oh, good answer Glenn, I could never remember the difference between petals & sepals? The ones around the flower bud. Thanks & Cheers Wendy – Hide quoted text — Show quoted text – I am sure others can go into more detail but a few things to get you started: Orchids are Monocots (less structured vascular development. Tend to have stems with vascular bundles as opposed to dicots which have more developed and specialized vascular structures. Xylem, phloem layers etc) Orchids are defined not by by the plant but by a distinctive flower structure 3 Petals, 2 alike 1 different 3 Petal Like Sepals (leaves covering the flower bud) A structure called a column which is the fused male and female parts. Most flowere have seperate stamens (male) and pistils (female) They also have some unique chromosomal traits I believe but leave that for the breeders to explain. Please be kind if I erred in any, my biology is becoming rather dated. Glenn

Response:

Hi all, I have been poking around trying to figure this out.  What exactly is an orchid?  What traits does a plant have to have to be a member of the Orchidaceae family? Thanks. Matthew Donadio   There are many characteristics ascribed to orchids, however, the single distinguishing feature is the column. Any plant which has a column is an orchid; and all orchids have a column. A few plants are mistaken for an orchid as they have a pseudocolumn, like Arisaema, the jack-in-the-pulpit, but this is not a true column, which is part of the sexual apparatus. Wilford Neptune

Response:

- Hide quoted text — Show quoted text – Hi all, I have been poking around trying to figure this out.  What exactly is an orchid?  What traits does a plant have to have to be a member of the Orchidaceae family? Thanks. Matthew Donadio   There are many characteristics ascribed to orchids, however, the single distinguishing feature is the column. Any plant which has a column is an orchid; and all orchids have a column. A few plants are mistaken for an orchid as they have a pseudocolumn, like Arisaema, the jack-in-the-pulpit, but this is not a true column, which is part of the sexual apparatus. Wilford Neptune

Of course, it should be pointed out that all orchids are members of the monocotyledonae (aka the Monocots), along with lilies, grasses, palms, bananas, etc.  As such, they most often have leaves with parallel veination (although some do have net-like veination in their leaves).  Orchids also have zygomorphic flowers (i.e. flowers that are bilaterally symmetrical, but not radially symmetrical… with a select few orchids being asymmetrical) composed of six parts, three sepals and three petals, although in some orchids, the sepals may become partially or completely fused to form a synsepal…rarely all three sepals are fused to form a cup.   At least two of the sepals (the lateral sepals) strongly resemble each other, while the third sepal may or may not appear different (Disas take this to the extreme) than the other two.  Two of the petals (lateral petals) strongly resemble each other, while the lip (or labellum) is at least somewhat different than the lateral petals.  With many orchids, the lip has become quite large and ornate compared to the other floral parts, while in some (Masdevallia and Disa come to mind), the lip and petals are greatly reduced with the sepals taking over the role of ornateness. — Prem – Animator, programmer, and orchid and fossil nut extraordinaire… – DNRC Title: Minister of Lightwave 3d Plugin Design Foolishness – Home – http://www.PremDesign.com "We in our foolishness thought we were wise He played the fool and He opened our eyes We in our weakness believed we were strong He became helpless to show we were wrong." "God’s Own Fool" – Michael Card

Response:

Hi all, I have been poking around trying to figure this out.  What exactly is an orchid?  What traits does a plant have to have to be a member of the Orchidaceae family? Thanks. — World MultiCom www.worldmulti.com

Response:

This answer is taken from "The Genus Paphiopedilum -Natural History and Cultivation" by Dr. G.J. Bream, Charles O. Baker and Margaret L. Baker, pages 14 and 15  I am just summarizing (sometimes verbatim) the characteristics all members of the orchid family have in common.  I am not explaining them as the book does.  Many of these terms have a specific meaning in taxonomy quite different from their normal every day use. Taxonomists rarely agree.  The Bakers have a website at http://www.orchidculture.com/ where you might find more info. Alternately a web search on any of the terms/flower parts listed below might provide you with pictures to help illustrate the definition being described. The inflorescences are indeterminate. The flowers are inferior. The flowers are bilaterally symmetric. The tepals of the outer whorl are usually referred to as sepals.  The lateral of the inner whorl are called petals. The median tepal of the inner whorl is called the Labellum. The number of stamens is always reduced. The median stamen of the outer whorl and the lateral ones of the inner whorl are developed as either fertile stamens or as more or less distinct staminodes. Stamens and style are fused into a gynostegium which forms a ‘column’ except in a few genera. The anthers are joined to the filament at its base (basifixed) or for some distance along the dorsal edge (dorsifixed). The pollen grains are single in the Apostasioideae and Cypripedioideae but cohere in tetrads in the majority of all other orchids. The ovary may be unilocular or triocular (one or three chambers) The style is more or less apically inflexed and terminated by a tri-lobed stigma with a wet surface. The development of the embryo sac is triggered by pollination.  Sometimes, the actual fertilization does not occur until five or six months after pollination. The embryo is always immature in the ripe seed. The seeds are very minute and numerous but vary considerably in shape and size. Upon germination the embryo forms a tubercle (protocorm) Under natural conditions most orchids will germinate only when a symbiosis with a fungus has been established.

– Hide quoted text — Show quoted text – Hi all, I have been poking around trying to figure this out.  What exactly is an orchid?  What traits does a plant have to have to be a member of the Orchidaceae family? Thanks. — World MultiCom www.worldmulti.com

Response:

Filed under: Orchid Flower

Related Posts