Trichomes flower

Small trichomes are found on various flower parts, for example, the base of the corolla, the upper portion of the immature achene, the stigma, pappus, and bracts (Figure 4.3). 

Blond Lebanese hash consists of a matrix including flower pistils, leaf and flower particle debris, non-resin-bearing cystolith hairs, conical trichomes and resin nodules. Above, this is shown magnified about 500 times by an electron scanning microscope. Below is water-pressed Afghani hash in which the resin nodules (magnified about 250 times) are largely undissolved. 

The cotton fibers used in textile commerce are the dried cell walls of formerly living cells. Botanically, cotton fibers are trichomes or seed coat hairs that differentiate from epidermal cells of the developing cottonseed. The cotton flower blooms only for one day and quickly becomes senescent thereafter. On the day of full bloom, or anthesis, the flower petals are pure white in most G. hirsutum varieties. By the day after anthesis, the petals turn bright pink in color and, usually by the second day after anthesis, the petals fall off the developing carpel (boll). The day of anthesis serves as a reference point for all subsequent events in the seed and fiber development. 

Of the drugs that are contained in cannabis products, it is A -tetrahydrocannab-inol (A -THC) (1) which is responsible for the pharmacological activity of cannabis. This compound is formed in the glandular trichomes (see below) which are found on the surface of the plant. Cannabis sativa is dioecious, that is, it has both male plants and female plants. These are most easily recognized at the flowering stage because the flower structures are different. The female plants are preferred because they produce more of the glandular trichomes and, as a consequence, are richer in cannabinoids. 

The glandular trichomes are the structures in which the cannabis resin is pro-dnced. These can be fonnd on the underside of the leaves, and occasionally on the stems, but are mainly associated with the flower structures, with female plants being particularly rich in such structures. The unicellular trichomes are found all over the plant, but interestingly, only point up the plant. The cystolithic trichomes are found all over the plant and may have oxalic acid crystals visible within their bases. If aU of these trichomes are found together, then the plant material can be definitively identified as Cannabis saliva, since no other plant displays such a combination [5]. However, some plants possess trichomes which may be confused with those present on Cannabis sativa [6, 7] and care should thus be taken in definitive identification. 

Feverfew. Tanacetum parthenium (L.) Schultz Bip. is an herb that was used in antiquity to reduce fever and pain. The literature is replete with anecdotal evidence of the usefulness uf the herb, and recent clinical studies have added more support. Feverfew is a member of the aster/dai.sy family. The plant tissues have a pungent smell and very bitter taste. The medicinal principle of feverfew is concentrated in hairy trichomes on the chiysanthemum-like leaves.The plant displays clusters uf daisy-like flowers with yellow centers and radiating white florets. Recent uses uf feverfew are for migraine and arthritis, although the indication for arthritis is disputable. The anecdotal evidence that an herb could successfully treat a condition such as migraine headache naturally begged for some seientifle proof. 

KAMALA which consists of the trichomes and glands separated from the fruits of Mallotus philippinensis (Lam) Miill. Arg., family Euphorbiaceae, a tree in India, Pakistan and the East Indies. Similar phlorogucine-type substances occur in Koso flos., which are the flowers of the Ethiopian tree Hapienia abyssinica, J.F.Gmelin, family Rosaceae. These two drugs have local use as anthelmintics against tapeworm. 

Floral scents are often complex blends of several compounds. These are mainly fatty-acid derivatives, benzenoids, phenylpropanoids, isoprenoids, nitrogen-and sulfur-containing compounds. Knudsen et al. s (1993) comprehensive review of floral odors reported floral scents with as few as three compounds and as many as several hundred. A study of moth-pollinated flowers from the Nyctaginaceae reported as many as 77 compounds in floral scent and as few as one. Studies that have focussed on identifying the site of volatile production in flowers report that they are produced mostly in the petals. Volatiles are both synthesized and released by the epidermal cells or by special glandular trichomes on the petal surface. Other studies have shown that the odor of pollen is also part of the odor signal. ... 

Conostegia are glabrescent to densely pubescent trees or shrubs with a variety of different trichome types. Leaves are usually petiolate, with only a few species having subsessile leaves. Flowers are grouped in inflorescences described as pleiothyrsoid, i.e. with cymose partial inflorescences (Fig 9.2A), which can... 

Sepals initiate in a rapid, almost simultaneous, sequence or initiation is unidirectional (Fig 12.3B). However, sepals become rapidly equal in size with a valv-ate aestivation (Fig 12.3C-E). The apical part of the sepal is initially developed in a massive protuberance, which overtops the rest of the flower (Fig 12.3F). The broad upper section becomes covered with small trichomes on the margins (Fig 12.3E,F), spreading to the whole sepal surface (Fig 12.3G). The sepals bear one large or a pair of sessile glands on each side arising as lobes on the margins (Fig 12.3E,F). At maturity sepals are more equal in size and spread open or become reflexed. 

Fig. 3. Distinguishing characteristics of Toxicodendrons useful for field identification [33]. (1) Buds are not terminal, causing new directions of growth each season. (2) The petiole is enlarged at the point of attachment. (3) U- or V-shaped leaf scars. (4) Flowers, fruit on panicles in axillary position. (3) Trichomes on fruit of poison oak and some ssp. of poison ivy. (6) Exocarp which peels away in the winter. (7) After losing exocarp, fruits are smaller and chalk white with tiny black lines like longitudinal lines on a globe. (8) Empty fruit stalk, (g) Lenticels give a characteristic texture to the wood...

The phytochemical diversity of C. saliva is well illustrated by more than 500 com-potmds isolated from this plant, encompassing all major classes of phytochemicals (polyketides, terpenoids, alkaloids, flavonoids, stilbenoids, oxylipins). Undoubtedly, the most important and peculiar secondary metabolites of C. saliva are cannabinoids, a class of mono- to tetracyclic C21 (or C22) meroterpenoids encompassing more than 100 members. These compounds are synthesized in secretory cells of glandular trichomes, most concentrated in unfertilized female cannabis flowers prior to senescence. A number of detailed accounts on the cannabinoid chemistry have been reported in the literature [6-8], also recently by Appendino et al. [9]. In this paragraph, we will provide an updated, although not comprehensive, account of the chemistry of this fascinating class of secondary metabolites. 

Phlorisovalerophenone synthase (VPS) from flower cones of hop (Humulus lupulus L.) utilizes isovaleryl-CoA or isobutyryl-CoA as starter molecules [24] (Fig. 2). Three molecules of malonyl-CoA are added to these starters to form phlorisovalerophenone or phorisobuty-rophenone, respectively, precursors for the biosynthesis of hop bitter acids. The first committed step of cannabinoid biosynthesis in glandular trichomes of Cannabis sativa is catalyzed by a stilbene synthase carboxylate-like (STCSL) polyketide synthase using n-hexanoyl-CoA as starter molecule, yielding olivetolic acid [25]. 

---