Capitate trichomes

Robert Connell Clarke s illustration of the development of the resin-producing glandular plant hair with a stalk (the capitate-stalked trichome) (1) single cell stage (2) trichome intially divides (3) head and stipe cells differentiate (4) epidermal stalk elongates as head cells finish dividing ... 

Sunflower (Helianthus annuus) causes allergic contact dermatitis in agricultural workers engaged in growing the plant for commercial purposes [152, 153, 154]. This sensitivity may produce a cross-reaction to Arnica [155]. The eruption commonly involves exposed sites and the hands. The SQTL antigen is located in fragile multicellular, capitated glandular trichomes [156]. 

Fig. 94.2 Glandular trichomes of sage Salvia officinalis) store essential oil composed of mono-terpenes. (a) Peltate glandular trichomes forming oil glands on lower leaf surface of sage, (b) Peltate glandular trichomes, capitate glandular trichomes and non-glandular trichomes on leaf veins of sage...

In aromatic herbs, members of the family Lamiaceae, the EOs can be foimd in two t3 es of glandular trichomes on the surface of their leaves, termed Ihe peltate and capitate glands (Gang et al. 2001). Figure 13.2 shows several terpenes present in EOs obtained from herbs of family Lamiaceae. These compounds are extremely volatile and have been demonstrated to possess multiple functional properties, including antioxidant (Riahi et al. 2013, Alves-Silva et al. 2013), antimicrobial (Ruiz-Navajas et al. 2012 Ballester-Costa et al. 2013), antitumor (Nikolic etal 2014), and antiviral (Usachev etal. 2013). 

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