New Aspects of Secretory Structures in Five Alismataceae Species: Laticifers or Ducts?

The secretory structures of Alismataceae have been described as secretory ducts, laticifer ducts, laticifer canals or schizogenous ducts. However, these terms are not found in the specialized literature, and ontogenetic analyses for the exact classification of these structures are missing. Accordingly, more studies regarding the secretory structures of Alismataceae are necessary to establish homology in the family or in the order. Thus, the aim of this study was to describe the anatomy, ontogeny, distribution in the organs and exudate composition of the secretory structures present in five Alismataceae species in order to determine whether the family has laticifers or secretory ducts. Samples of leaves, flowers and floral apices were processed for anatomical and histochemical analyses by light microscopy. The analysis indicated the presence of anastomosing secretory ducts in all species, occurring in both leaves and flowers. The exudate contains lipids, alkaloids, proteins and polysaccharides, including mucilage. The secretory duct structure, distribution and exudate composition suggest a defense role against herbivory and in wound sealing. The presence of secretory ducts in all species analyzed indicates a probable synapomorphy for the family.

Comparative study of the leaf’s anatomical structure of some endemic species Umbelliferae family in Middle Asia

This article presents the results of comparative study of leaf structure in species Komarovia anisosperma,Sphaerosciadium denaense, Kamelinia tianschanica, Korshinskya olgae и Autumnalia innopinata of the Apiaceae Lindlfamily. For the studied species, a close relationship between the anatomical structure of the leaf and environmental conditions has been revealed. The diagnostic leaf-blade features are: for Komarovia anisosperma, single layer of the palisadeparenchyma with tightly closed or in places loosely located rather elongated cells and the presence of 3 secretory ducts onthe abaxial side (under the central and marginal lateral vascular bundles); for Sphaerosciadium denaense, marginal partswrapped to adaxial side, 2(3) secretory ducts above the main bundle at the abaxial side, one larger at the adaxial side,above and below lateral bundles they locate one by one, and a single duct at the adaxial part of the leaf top; for Kamelinia tianschanica, two and above the central bundle three-layer palisades and the presence of a single secretory duct underthe central bundle; Korshinskya olgae, two-layer palisade and the presence on the abaxial side of 3 (4) secretory ducts (1or 2 large under the central and median lateral vascular bundles); Autumnalia innopinata, isopalisade mesophyll and thepresence of a 2–3-layer aquifer parenchyma.

Secretory duct distribution and leaf venation patterns of Aldama species (Asteraceae) and their application in taxonomy

Features of leaf morphology such as secretory duct distribution and venation patterns are important taxonomical tools; however, some species can have variation in these traits. This study evaluates whether the secretory duct distribution in the midrib and venation is similar across different leaves of 17 Aldama species. Six fully expanded leaves (three each of the largest and smallest size) from five distinct plants were selected to analyze the duct distribution. The samples were histologically examined, and the quantitative data were statistically analyzed. The venation pattern was analyzed in five fully expanded leaves of different plants. In all, 23 secretory duct distribution patterns were identified; they showed intra- and inter-species variations except in Aldama anchusifolia (DC.) E.E.Schill. & Panero and A. trichophylla (Dusén) Magenta. The largest number of ducts was not correlated with leaf and midrib dimensions (width and length). Further, Aldama venation could be divided into two groups: (1) pinnate camptodromous brochidodromous type (four species), and (2) acrodromous venation type and its basal and suprabasal variations (13 species). Thus, distinct secretory duct arrangements of the midrib might assist in the discrimination of Aldama species. The venation patterns were also important for distinguishing the majority of species selected.

Cypselar anatomy of five species of the tribe Calenduleae, family Asteraceae

Detailed anatomical features of cypselas of five species (Calendula arvensis L., Calendula maderensis DC., Calendula stellata Cav., Calendula suffruticosa Vahl ssp. suffruticosa and Osteospermum vaillantii (Decne.) Norl.) of the tribe Calenduleae have been studied to observe the variation pattern among them. Among the five cypselas, in case of C. stellata, mesocarpic region is made up of only parenchyma cells, containing pits. In remaining four cypselas, mesocarpic region is made up of both parenchyma and sclerenchyma cells. In the cypsela of O. vaillantii, vallecular cavity is present in mesocarpic region. This cavity is absent in remaining four cypselas. In the cypsela of C. arvensis and C. suffruticosa, secretory duct exists in mesocarpic region, which is absent in remaining three cypselas. In the cypsela of C. arvensis and C. maderensis, six vascular traces are present in mesocarpic region, whereas in O. vaillantii, eight vascular traces; in C. stellata, five vascular traces; in C. suffruticosa, four vascular traces are present in mesocarpic region. Based on the above mentioned anatomical features, an artificial key to the species has been constructed.Journal of Bangladesh Academy of Sciences, Vol. 39, No. 1, 65-71, 2015

The Harderian gland of the northern grasshopper mouse, Onychomys leucogaster

The Harderian gland of the northern grasshopper mouse, Onychomys leucogaster, consists of glandular tubuloalveolar endpieces with secretory cells (small- and large-droplet cells) surrounding a wide lumen. Lumina from adjacent endpieces join repeatedly, forming progressively wider channels. Ultimately, a single secretory duct opens at the anterior canthus of the eye. Abundant sudanophilic materials secreted into the lumina of the tubuloalveoli drain into the orbit of the eye. The presence of amber–brown concretions in, and the intense fluorescence of, the Harderian gland suggest that in O. leucogaster the secretory materials also include porphyrins. Fluorescence of these secretions demonstrates that they drain from the orbit into the nasal passages; grooming spreads these materials from the nares onto other parts of the body. Although the Harderian gland of O. leucogaster shows no sexual dimorphism, there are age-related changes. Small-droplet cells are present at 1 week of age and large-droplet cells appear by 2 weeks. By 4 weeks the gland is comparable to that of adults. Glands of a few adults exhibit two features rarely reported in other rodents: (1) clusters of degenerated tubules characterized by a loss of the secretory epithelium and (2) large aggregations of lymphoid cells.