Trichomes cell wall

As depicted in Fig. 3, in glandular trichoma the cannabinoids are produced in the cells but accumirlate in the secretory sac of the glandular trichomes, dissolved in the essential oil [17-21]. Here, A9-THC was found to accumulate in the cell wall, the fibrillar matrix and the surface feature of vesicles in the secretory cavity, the subcutilar wall, and the cuticula of glandular trichomes [19]. 

Marks MD, Betancnr L, Gilding E, Chen F, Baner S, Wenger JP, Dixon RA, Haigler CH. (2008) Anew method for isolating large qnantities of Arabidopsis trichomes for transcriptome, cell wall and other types of analyses. Plant J 56 483 92. 

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. 

Suberin is laid down in the cell wall of calcium oxalate crystal idioblasts. This deposition has been characterized in crystal cells in the bark of Larix decidua, Acacia Senegal, and Picea abies (481, 482). The suberin in crystal idioblast cell walls from Agave americana was characterized both ultrastructurally (Fig. 6.4.3) and chemically, and the major aliphatic component was shown to be octadocenedioic acid (25%) (117). The basal walls of leaf trichomes are suberized as shown in Abutilon megapotamicum (161), Ananas comosus (395), and Larrea tridentata (451). The walls of oil cells found in Acorus calamus (9) and Laurus nobilis (291) also appear ultrastructurally to be suberized. Suberized cells encircle silica cells in the stem of Lolium temulentum (271). In all of the cases listed above, the suberin may serve to protect the rest of the plant from potentially toxic components. 

The covering trichomes, which are usually found attached to small fragments of the epicarp, are pluricellular, multi-seriate and rounded at the apex, vary in length and are composed of fairly thick-walled cells. 

Subsequent colonization patterns, after application of microbes to leaves, appear to be nonrandom. Leben (67) observed that 19-28 days after inoculation of leaf buds of cucumber seedlings with suspensions of Pseudomonas syringae pv. lachrymans the bacterium appeared to be distributed uniformly on the two expanding leaves below the bud (by leaf imprints on a selective medium). However, on older leaves the bacterium was usually distributed nonrandomly, often found associated with epidermal cells on leaf veins and with basal cells of trichomes on veins. Bacterial aggregates were generally less prevalent on older leaves. The distribution on older leaves was thought to be related to leaf moisture (67). Blakeman (79) reported that bacterial or yeast cells immediately after inoculation onto bean leaves (Vicia faba L.) were evenly distributed on anticlinal walls of epidermal cells. Later, differential colonization was detected (79). When... 

Two of the most common Hemiaulus species reported with symbiotic R. intracellularis are H. hauckii and H. membranaceus. A third symbioses, occurs between Richelia and H. sinensis. In Hemiaulus host diatoms, it is not known where the symbiotic Richelia reside, whereas in Rhizosolenia spp. hosts, the Richelia remains as an extracellular endosymbiont residing between the plasmalemma and silica wall of the diatom host (Janson et ai, 1995 Taylor, 1982 ViUareal, 1990). In Hemiaulus diatoms, typically there are two trichomes (series of cells comprised of a few vegetative cells and one terminal heterocyst) per host cell, and in Rhizosolenia species occasionally 1-32 Richelia trichomes have been observed (Siindstrom, 1984 Villareal, 1990). 

Fig. 9. Cross section of a bract from the fruiting plant a, cystolith hair A large grandular hair with several cells in head and stalk c, head of one of the large glandular hairs d, small glandular hair with bicellular head artd unicellular stalk e, thick walled conical trichomes f, large developing glandular hair i stalk of a large glandular hair h, palisade cell /, cluster crystal / parenchymal cell /r, stomata. (Reprinted by permission, from Joyce and Curry, The Botany and Chemistry of Cannabis, 1970. Drawn by D. Erasmus.)...

Fig. 7-10. Leaf cross sections of Phaseolus vulgaris > hybrids of Populus sp., and Quercus palustris after one to several rainfalls of simulated acid rain of low pH. Fig. 7. Initial injury of epidermal cells near a trichome hydathode. Note injury is greatest at the anticlinal walls of epidermal cells at the base of a hydathode on P. vulgaris. Fig. 8. Initial injury of subsidiary cells near the guard cells of a stoma. The cells of the palisade parenchyma appear normal on P. vulgaris. Fig. 9. A large lesion with an injured adaxial epidermis, palisade parenchyma, and spongy parenchyma near vascular tissues in poplar. Fig. 10. A cross-section of a gall on a leaf of palustris. Note both collapsed epidermal and palisade cells. Hypertrophy and hyperplasia of spongy mesophyll cells are also evident.

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