This is not a comprehensive glossary of botanical terms, but only a list of the terms used in the botanical section of this website. It was put together so that users reading the posts in the botanical section need not go through it with a botanical reference book at hand.
Papery (upper) and leafy bracts on hay rattle (Rhinanthus minor). All the "leaves" in this image are bracts.
A bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis, or cone scale. Bracts are often (but not always) different from foliage leaves, for example being smaller, larger, or of a different color or texture. Some bracts are brightly colored and serve the function of attracting pollinators, either in concert with or instead of the perianth. An excellent example of this latter type of bract occurs in the Poinsettia plant (Euphorbia pulcherrima), which has small green flowers, surrounded by large scarlet bracts. Considering the broadest meaning of the term, any leaf associated with an inflorescence is called a bract. A bract is usually located at the node where the main stem of the inflorescence forms, joined to the main stem of the plant, but other bracts can exist within the inflorescence itself.
The corm in Taro (Colocasia esculenta, Arbi in Hindi)
A corm (or bulbo-tuber, bulbotuber) is a short, vertical, swollen underground plant stem that serves as a storage organ used by some plants to survive winter or other adverse conditions such as summer drought and heat (estivation). A corm consists of one or more internodes with at least one growing point, with protective leaves modified into skins or tunics. The thin tunic leaves are dry papery, dead petiole sheaths, formed from the leaves produced the year before, which act as a covering that protects the corm from insects and water loss. Internally a corm is mostly made of starch-containing parenchyma cells above a circular basal node that grows roots.Corms are sometimes confused with true bulbs; they are often similar in appearance to bulbs externally, and thus erroneously called bulbs. Corms are stems that are internally structured with solid tissues, which distinguishes them from bulbs, which are mostly made up of layered fleshy scales that are modified leaves. As a result, when a corm is cut in half it is solid, but when a true bulb is cut in half it is made up of layers. Corms are structurally plant stems, with nodes and internodes with buds and produce adventitious roots. On the top of the corm, one or a few buds grow into shoots that produce normal leaves and flowers.
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified. The modifications can involve the length and the nature of the internodes and the phyllotaxis, as well as variations in the proportions, compressions, swellings, adnations, connations and reduction of main and secondary axes. The stem holding the whole inflorescence is called a peduncle and the main stem holding the flowers or more branches within the inflorescence is called the rachis. The stalk of each single flower is called a pedicel.The fruiting stage of an inflorescence is known as an infructescence. A flower that is not part of an inflorescence is called a solitary flower and its stalk is also referred to as a peduncle.
A spadix is a type of spike inflorescence having small flowers born on a fleshy stem. Spadix are typical of the Family Araceae known as arums or aroids. The spadix is typically surrounded by a leaf like curved bract known as a spathe For example, the “flower” of the well known Anthurium spp is a typical spadix with a large colorful spathe.
A spathe is a large bract that forms a sheath to enclose the flower cluster of certain plants such as palms, arums, and day flowers. In many arums, the spathe is petal-like, attracting pollinators to the flowers arranged on a type of spike called a spadix.
Succulent plants, also known as succulents or fat plants, are water-retaining plants adapted to arid climate or soil conditions. Succulent plants store water in their leaves, stems, and also in roots.
If you would like to make a comment, please fill out the form below.
