New Data on Seed Coat Micromorphology of Several Impatiens spp. from Northeast India

Abstract

This study aimed to analyze the seed coat structure of nine species from the genus <em>Impatiens </em>from Northeast India. A review of the available literature showed a scarcity of data on seed sizes and shapes, as well as a complete lack of information on the ultrastructure of seeds from five taxa of <em>Impatiens </em>determined with a scanning electron microscope (SEM). Photographs of the surface structure of seeds from the analyzed species were taken using an SEM and, from these, we measured the length and width of the seeds. The results showed differences in the seed ultrastructure and metric traits within the studied taxa. Based on the ornamentation of the epidermal cells, we distinguished three morphological types: protrusive, granulate, and reticulate. The seeds of the investigated species had ellipsoid, subellipsoid, or subspheroid shapes. Their lengths and widths ranged from 1.2 to 3.6 mm and 0.7 to 2.1 mm, respectively. The results of the study showed that the ultrastructures of <em>Impatiens </em>seeds are different among taxa and for some species can be used as a diagnostic character for their identification.

Evolution and Taxonomic Significance of Seed Micromorphology in Impatiens (Balsaminaceae)

“…Cai et al (2013) examined the seeds of 24 species of Impatiens from China and divided them into two major types: reticulate type and protrusive type, and briefly discussed the systematic taxonomic significance of the micromorphology of the seed coat. Furthermore, fragmented studies on the seed coat of Impatiens were investigated by Lu and Chen (1991) , Tian (2004) , Chen (2007) , Fischer et al (2017) , Yin (2018) , Najberek et al (2020) , and Rewicz et al (2020a , b) . However, due to insufficient sampling, it was hard for these studies to provide a comprehensive conclusion on the overall variation in seed coat micromorphology in Impatiens .…”

The Mexican Balsam, Impatiens mexicana Rydb: A Redescription Based on Morphological and Phylogenetic Studies, with an Update of the Current Geographical Range of the Species

“…These detailed studies would make it possible to anticipate a better separation through the application of different multivariate discrimination methods, such as those successfully to the North American species I. capensis from I. pallida [88]. Likewise, it is notable that, in various species of Impatiens, micromorphological attributes have been of particular use in the species´separation, especially those that lie in pollen and seeds (e.g., [4,15,[89][90][91][92][93]). Future exploratory studies of the Mexican balsam and American species should acknowledge this, and take into account the fact that knowing the variations will improve the separation process.…”

Seed variability of Sisymbrium polymorphum (Murray) Roth (Brassicaceae) across the Central Palaearctic

“…The differences in the structure of seeds allow for distinguishing individual units at different levels of hierarchy, making them useful in plant taxonomy and identification (Saadaoui et al 2013;Rewicz et al 2017Rewicz et al , 2020Martín-Gómez et al 2019a, 2019bUllah et al 2019). The properties of seeds, such as sculpture variability, are the subject of many scientific studies (Vaughan and Whitehouse 1971;Stace 1993;Gamarra et al 2010;Kaya et al 2011;Meyer et al 2015;Rewicz et al 2016).…”