Seed Morphology of 12 Taxa of the Genus Thalictrum L. (Thalictroideae, Ranunculaceae) and its Systematic Implication

Balkrishna Ghimire,Go Eun Choi,Hayan Lee,Mi Jin Jeong,Cheul Ho Lee,Gang Uk Suh,Kweon Heo,Sung Won Son 한국원예학회 2016 한국원예학회 학술발표요지 Vol.2016 No.5

Seed Atlas of Korea I. Conifers

Balkrishna Ghimire,Dabin Yeom,Mi jin Jeong 국립중앙과학관 2019 Journal of Asia-Pacific Biodiversity Vol.12 No.3

Seed morphology of 17 taxa of conifers belonging to ten genera and four families is investigated using stereomicroscope and scanning electron microscope. Embryo types of corresponding taxa are also identified. The important seed features were found as seed shape, size, presence or absence of wing, and surface microsculpture. The seed surface microsculpture was dominated by colliculate type representing Pinus, Tsuga, and Taxus species. The embryo was axial linear in all species, although variation on embryo size was prevalent. Despite the limited range of taxa comprised, the seed macro and micro morphological features were found useful for future taxonomic study within the conifer species.

Embryo, Seed coat and Pericarp Development in Abeliophyllum distichum Nakai (Oleaceae): A Rare and Endemic Plant of Korea

Balkrishna Ghimire,정미진,최고은,이하얀,이경미,이철호,서강욱 한국자원식물학회 2015 한국자원식물학회지 Vol.28 No.3

Abeliophyllum distichum is a monotypic taxon of Oleaceae and endemic to Korea. A comprehensive study on embryogeny and fruit and seed coat ontogeny in Abeliophyllum was carried out via microtome and light microscopy. The fertilization occurs during mid– to late April and embryo matures by early July. The embryo development follows the general fashion from globular embryo – transition embryo – heart shaped embryo – torpedo embryo – walking-stick embryo to mature embryo. The pericarp clearly differentiates into three histological zones: exocarp, mesocarp, and endocarp. The young seed comprises 10-12 cells thick seed coat and the mature seed coat comprises an exotesta, 6-8 mesotesta and an endotesta. Any crystals, phenolic-like compounds, idioblasts, and the sclereids are not found in pericarp as well as seed coat. An overall development confirms Solanade type of embryogenesis in Abeliophyllum. The endocarp becomes more prominent in mature fruit and all the layers of endocarp are highly lignified. On the basis of mechanical layer the seed coat is of exotestal type.

Embryology of Gymnospermium microrrhynchum (Berberidaceae)

Balkrishna Ghimire,신동용,허권 한국식물분류학회 2010 식물 분류학회지 Vol.40 No.4

An intensive study of the embryology of Gymnospermium microrrhynchum was conducted to provide information regarding a discussion of the phylogenetic relationships of the genus, which is yet unstudied. Our results indicated that Gymnospermium is similar to other genera of Berberidaceae in terms of its embryological features. Nevertheless, newly reported and unique features are the well-developed endothelium and the undifferentiated seed coat type. Until the study of Gymnospermium, it may have been considered to be closer to Caulophyllum and Leontice in the tribe Leonticeae. These three genera share many morphological features as well as molecular similarities, by which they are kept in the same tribe, Leonticeae. However, very little detailed embryological data regarding these genera have been published thus far. Gymnospermium was characterized according to the basic type of anther wall formation as well as its glandular tapetum, successive cytokinesis in the microspore mother cell, two-celled mature pollen grains, anatropous and crassinucellate ovules with a nucellar cap, well-developed endothelium, its Polygonum type of embryo sac formation, its nuclear type of endosperm formation, and its undifferentiated seed coat type. In comparison with Nandina, there are many differences, such as the dehiscence of the anther, the cytokinesis in the microspore mother cells, the shape of the megaspore dyad, and the seed characteristics. Although we had no available detailed embryological information regarding Caulophyllum and Leontice, which are genera that are more closely related to Gymnospermium, we could deduce from the phylogenetic relationship that Gymnospermium, Caulophyllum, and Leontice are more closely related to each other than other genera of Berberidaceae on the basis of the seed characteristics.

Seed characteristics of Withania somnifera (Solanaceae)

Balkrishna Ghimire,허권,Bimal Kumar Ghimire 한국식물분류학회 2011 식물 분류학회지 Vol.41 No.2

The seed characteristics of Withania somnifera were studied using light and scanning electron microscopy in order to determine the specific features of this species. The seed color is yellow, and the seed shape is reniform measuring between two to three millimeters. The seed of W. somnifera is exarillate and albuminous. The seed coat type is exotestal. The seed coat develops from a single integument. The young seed coat consists of single-layered exotesta, multi-layered mesotesta and single-layered endotesta. However, parenchymatous mesotesta layers are completely compressed at maturity. Therefore, the seed coat was represented by sclerenchymatous exotesta. The primary sculpture on the seed surface is reticulate, and cells are irregular in shape with undulating anticlinal walls. In addition, the seed surface has several characteristic holes between the anticlinal walls.

Embryology of Jeffersonia dubia Baker et S. Moore (Berberidaceae) and comparison with allied genera

Balkrishna Ghimire,허권 한국식물분류학회 2012 식물 분류학회지 Vol.42 No.4

Because the embryological features of Jeffersonia dubia are poorly understood, we conducted the first embryological study comparing it to other related genera of Berberidaceae. Important embryological features of J. dubia are as follows: the anther is tetrasporangiate, anther wall formation confirms basic type, glandular tapetum cells are two nucleate, the epidermis persistent, and the endothecium develops fibrous thickenings, anther dehiscence by two valves, meiosis in a microspore mother cell is accompanied by simultaneous cytokinesis, microspore tetrads are usually tetrahedral, pollen grains two cells at the time of anthesis. The ovule is bitegmic, anatropous and crassinucellate, archesporium single celled, development of the embryo sac Polygonum type, a mature embryo sac is ellipsoidal in shape. Endosperm formation is of Nuclear type and embryogeny Onagrad type. Seeds are arillate and seed coat exotestal type. Embryological comparisons showed that Jeffersonia resemble to Epimedium and Vancouveria rather than Berberis and Mahonia in some features, like as number of tapetal cells, cytokinesis in meiosis, and thickness of exotesta. It also resembles to Gymnospermium in mode of anther wall formation, number of tapetal cells, formation of nucellar cap, and nature of antipodal cells. Nevertheless, Jeffersonia and Gymnospermium differ from several other embryological features and molecular data too. Therefore, embryological evidences support that Jeffersonia is closely related with Epimedium and Vancouveria.

Embryological studies on <i>Abelia tyaihyoni</i> Nakai (Caprifoliaceae)

Ghimire, Balkrishna,Suh, Gang Uk,Lee, Cheul Ho,Heo, Kweon,Jeong, Mi Jin Elsevier 2018 Flora Vol.242 No.-

<P><B>Abstract</B></P> <P> <I>Abelia tyaihyoni</I> is a Korean endemic species and also designated as an endangered taxon in the IUCN Red List. We present a comprehensive embryology of <I>A. tyaihyoni</I>, comparing it with previously available information on the Caprifoliaceae and related families, and identifying possible evolutionary trends. Overall, comparisons showed that <I>Abelia</I> is similar to the other genera of Caprifoliaceae in many embryological features, including the tetrasporangiate anther, the anther wall, dicotyledonous wall formation, fibrous endothecium, simultaneous cytokinesis, tetrahedral tetrads, and three-celled pollen grains. In addition, <I>Abelia</I> share anatropous, unitegmic, and tenuinucellate ovules, ephemeral antipodals, and a cellular-type endosperm with many caprifoliaceous genera. Some embryological features, such as the amoeboid tapetum with several nuclei forming a polyploid mass, bisporic <I>Allium</I>-type embryo sac, obturator, bilayered endocarp, and compressed exotesta, are here described for the first time in this genus. The results confirm that <I>A. tyaihyoni</I> shares some significant embryological features with other Caprifoliaceae. Although previous embryological studies on the Caprifoliaceae lack convincing evolutionary explanations, our comparative approach demonstrates some possible apomorphies in <I>Abelia</I> such as the presence of two sterile carpels, bisporic <I>Allium</I>-type embryo sac, single-seeded fruit, bilayered and sclerified endocarp, and compressed exotesta.</P> <P><B>Highlights</B></P> <P> <UL> <LI> <I>Abelia</I> is similar to the other Caprifoliaceae in many embryological features. </LI> <LI> Amoeboid tapetum with several nuclei forming polyploidy mass is new to the genus. </LI> <LI> Bisporic <I>Allium</I> type of embryo sac and obturator formation is also new to the genus. </LI> <LI> <I>Allium</I> embryo sac, bilayered endocarp & compressed exotesta are possible apomorphies for the family. </LI> </UL> </P>

Leaf anatomy of Pinus thunbergii Parl. (Pinaceae) collected from different regions of Korea

Balkrishna Ghimire,김무열,이정호,허권 한국식물분류학회 2014 식물 분류학회지 Vol.44 No.2

Leaf anataomical study of Pinus thunbergii collected from 12 different coastal regions of Korea was conducted to understand the adaptive variation on leaf traits. Basic anatomical features are typical pine needle type with fibrous epidermis, 2-3 layered hypodermis, sunken stomata, monomorphic mesophyll, and well-represented bundle sheath. The bundle sheath surrounds a couple of vascular bundle separated by parenchyma bands. On the basis of their position, the resin ducts are of three types; external, medial and internal of the bundle sheath. The total number of resin ducts in all samples varies from 4 to 12. The stomata were found on stomatal bands throughout the leaf surface. Important dissimilarities observed on P. thunburgii leaf are the number and position of resin ducts and the number of stomata rows in leaf surface.

Wood anatomy of Korean Symplocos Jacq. (Symplocaceae)

Balkrishna GHIMIRE,박범균,오승환,이재동,손동찬 한국식물분류학회 2020 식물 분류학회지 Vol.50 No.3

Despite poorly documented species delimitation and unresolved taxonomic nomenclature, four species of Symplocos (S. coreana, S purnifolia, S sawafutagi, and S. tanakana) have been described in Korea. In this study, we carried a comparative wood anatomy analysis of all four species of Korean Symplocos to understand the wood anatomical variations among them. The results of this study indicated that Korean Symplocos are comparatively indistinguishable in terms of their qualitative wood features, except for exclusively uniseriate rays present in S. purnifolia instead of uniseriate to multiseriate in other three species. Nevertheless, differences are noticed in quantitative wood variables such as the vessel density, vessel size, and ray density. The vessel density of S. purnifolia is more than twice as high as those of S. sawafutagi and S. tanakana. In contrast, the vessel circumference and diameter on both plants of S. sawafutagi and S. tanakana is nearly twice as large as those of S. purnifolia. Symplocos coreana has characteristic intermediacy between these two groups in terms of vessel features and is closer to S. purnifolia in terms of its ray density level. A cluster analysis based on a paired group (unweighted pair-group method with the arithmetic mean, UPGMA) algorithm using the Euclidean similarity index clearly differentiates S. purnifolia from the remaining species, representing the first branch of the phenogram.

Seed morphology and seed coat anatomy of <i>Fraxinus</i> , <i>Ligustrum</i> and <i>Syringa</i> (Oleeae: Oleaceae) and its systematic implications

Ghimire, Balkrishna,Jeong, Mi Jin,Suh, Gang Uk,Heo, Kweon,Lee, Cheul Ho Wiley (Blackwell Publishing) 2018 Nordic journal of botany Vol.36 No.10