Hairs, glandular

FIGURE 2 Glandular hairs on surface of pupa of the Mexican bean beetle, Epilachna varivestis. The secretory droplets contain such azamacrolides as ep-ilachnene (27). (Bar = 0.1 mm.)... 

Microscopic examination showed the pupae of the Mexican bean beetle Epilachna varivestis to be covered with glandular hairs, each having a droplet of oil at its tip. Attygalle and co-workers undertook a chemical analysis of this secretion, which resulted in the identification of a novel family of alkaloids, the azamacrolides [40]. Five compounds (27-31) (Fig. 6) were identified by GC-EIMS from the secretion, with epilachnene (27) comprising over 90% of the volatile material. 

In Subcoccinella 24-punctata, pupal surface also bears glandular hairs that produce a secretion principally made of the three PAMLs 58-60, which correspond to the three possible dimers of the two unsaturated (co-3)-(2-hydroxy-ethylamino)acids 56 and 57 (Fig. 10) [56]. The structure of the three PAMLs were based on NMR investigations and HPLC analyses, and were fully confirmed by total synthesis [57]. Smaller amounts of isomeric amides 61-64 and of the four possible cyclic trimers 65-68 were also detected (Figs. 10 and 11). 

A synthesis of the mayolenes, defensive lipids from the glandular hairs of the cabbage butterfly Pieris rapae (see above), has recently been described [174]. 

Heimich, G. et al.. Glandular hairs of Sigesbeckia jorullensis Kunth (Asteraceae) morphology, histochemistry and composition of essential oil, Ann. Bot., 89, 459, 2002. 

Bosabalidis, A., Gabrieli, Ch., and Niopas, J., Elavone aglycones in glandular hairs of Origanum X intercedens, Phytochemistry, 49, 1549, 1998. 

Plants have served as a food source for fish. Insects, and mammals since early biotic times. In response plants have developed intricate physical as well as chemical protective mechanisms. The two defensive structures that are the primary subject of this chapter are trichomes and glands. Trichomes are epidermal appendages of diverse form and structure, such as protective and glandular hairs and scales or peltate hair. 

A number of plants of the Solanum and Nlcotlana genera are particularly adept at producing sticky leaf exudates. In some wild potato species, an exudate is discharged from glandular hairs when aphids mechanically rupture the cell walls (33). The clear, water soluble exudate is stable in the absence of O2,... 

The drug digitalis is prepared mostly from leaves of the second year s growth. These are rather coarse ovate leaves covered with glandular hairs. Decoctions of Ihe leaves have been used in Europe for many years. 

Mechanical protection is provided by thorns, spikes, trichomes, glandular hairs, and stinging hairs (which are often supported by defense... 

Water soluble compounds are usually stored in the vacuole (Matile, 1978, 1984 Boiler and Wiemken, 1986 Wink, 1993, 1997 Terasaka et al, 2003 Kutchan, 2005 Yazaki, 2005, 2006) (Table 1.2), whereas lipophilic substances are sequestered in resin ducts, laticifers, glandular hairs, trichomes, thylakoid membranes or on the cuticle (Wiermann, 1981 Kutchan, 2005) (Fig. 1.5). 

Mesophyll, of irregular shaped chlorphylloid cells, containing abundant chloroplasts. Intercellular-air-spaces are found between various cells which are larger in the lower than in the upper region. Internal glandular-hairs are frequently to be discerned in many of these spaces. 

Hair cystoliths differ from the average type in that they are devoid of a stalk. Such are seen in the non-glandular hairs of Cannabis sativa. 

Dermatogen originates epidermal tissue and derivative structures such as stomata, non-glandular and glandular hairs, glands, and cork cambium. 

The intoxicating resin is secreted by glandular hairs located around the flowers and to a certain extent in the lower portions of the plant. The actual substance in the resin responsible for the plant s inebriating effects is a chemical called delta-9-tetrahydrocannabinol (THC). In very hot climates, as in India and North Africa, so much resin is produced that the plant appears to be covered with a sticky dew even as it bakes under the parching rays of the hot sun. This resin serves as a protective shield preventing loss of water from the plant to the dry air. And of course, the more resin, the more THC likely to be present. 

Glandular with a secretive function. In glandular hairs the... 

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