PJB-2023-1574
Seedling structure and surface micromorphology of Sterculia foetida L. (Malvaceae)
D. Khan and Rubina Abid
Abstract
The seedling structure and surface micromorphology of Sterculia foetida L. (Malvaceae) is described. Seedling of S. foetida may be Phanerocotylar-epigeal - Reserve type or Cryptocotylar – hypogeal - Reserve type. When aboveground, cotyledons unfolded, expanded and turned green on exposure to sun, developing dense crop of trichomes. The whole seedling surface was trichomatous. Cotyledonary trichomes were conical and multicellular. Some four kinds of trichomes were observed on leaflets. 1) Long, apically pointed non-glandular unicellular (acicular) trichomes – predominantly abundant. 2) Long, apically curved or hooked, unicellular or uniseriate multicellular trichomes. 3) Long apically club- shaped, Bicellular, uniseriate glandular trichomes. 4) Dark globular (ball-like, peltate) glandular trichomes on the midrib. Epidermal cells in cotyledons were polygonal and straight in anticlinal contour. The adaxial epidermis of leaf was with straight to curvy anticlinal walls and abaxially the epidermal cells were sinuous and irregular in shape. A diversity of stomatal complexes was recorded on cotyledons and leaflets. Stomatal density was lesser on cotyledonary sun-exposed surface than that of leaflets. Leaflets were hypostomatous. Foliar stomatal density varied with the size of leaflets. Stomatal density in the smallest leaflet of 184 mm2 was 249.14 ± 5.54 (varying from 157.26 to 324.36 stomata per mm2, CV: 14.05%) and 125.22 ± 3.449 stomata per mm2 in the largest leaflet (4709 mm2). Stomatal size inclusive of normal and giant stomata averaged to 21.15 ± 14.86 µm x 14.86 ± 0.176 µm (L x W) in 265 observations. It may be concluded that S. foetida is quite rich in trichomal and stomatal diversity
To Cite this article:
Khan, D. and R. Abid. 2023. Seedling structure and surface micromorphology of Sterculia foetida L. (Malvaceae). Pak. J. Bot., 55(6): DOI: http://dx.doi.org/10.30848/PJB2023-6(34)
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