Balkrishna Ghimire - Academia.edu (original) (raw)

Papers by Balkrishna Ghimire

A study on the regeneration of the Abies spectabilis (D. Don) Mirb. (Himalayan silver fir) in the... more A study on the regeneration of the Abies spectabilis (D. Don) Mirb. (Himalayan silver fir) in the northern aspect of the Manang valley was carried out during May- October 2004. The altitude ranged from 3500-4000 m a.s.l. and the forest was mixed forest of which lower belt was dominated by Pinus wallichiana with few pure stands of Abies spectabilis and upper belt (above 3800 m) was dominated by Betula utilis. The size class distribution of Abies spectabilis resembled the reverse J-shaped curve. However, there was lack of large girth class trees. Seedling and sapling density was abundant. Density of seedlings and saplings was correlated with phosphorus (p=0.01), but other soil factors did not show significant relation. Regeneration potential was low under its own canopy.

Korean Journal of Plant Resources, 2015

Korean Journal of Medicinal Crop Science, 2015

Botanical Journal of the Linnean Society, 2016

Korean Journal of Plant Taxonomy, 2012

Acta Botanica Brasilica, 2015

Korean Journal of Plant Taxonomy, 2014

Flora - Morphology, Distribution, Functional Ecology of Plants, 2015

Because the embryological features of Jeffersonia dubia are poorly understood, we conducted the f... more 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 Epimedi...

Leaf anatomical study of Pinus thunbergii collected from 12 different coastal regions of Korea wa... more Leaf anatomical 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.

Plant Systematics and Evolution, 2014

ABSTRACT Comprehensive comparative anatomy of Pinus leaves was carried out. Some anatomical featu... more ABSTRACT Comprehensive comparative anatomy of Pinus leaves was carried out. Some anatomical features were found to be quite useful and supported the classification of genus to subgenus and section level. The number of needles per fascicle, number of vascular bundles, position of resin ducts, shape of leaf in cross section, and distribution of stomata on the leaf surface showed remarkable variation between different species and facilitated the classification of Pinus into minor groups: subgenus, section, and subsection. The members of subgenus Pinus had two vascular bundles whereas members of subgenus Strobus had only one vascular bundle. The position of resin ducts was more consistent in subgenus Strobus than in subgenus Pinus. Interestingly, the species of subsection Strobus included in this study lacked stomata on the abaxial surface. The results indicate that the number of needles per fascicle and needle size are inversely related, and more importantly that a greater numbers of needles per fascicle lead to a more angular shape.

Himalayan Journal of Sciences, 2011

We studied the elevational pattern of forest composition and regeneration of the subalpine conife... more We studied the elevational pattern of forest composition and regeneration of the subalpine conifer tree species Pinus wallichiana in Manang, a trans-Himalayan dry valley in north-central Nepal. Thirty-five quadrats (10 m × 10 m) were laid between 3300 and 4000 masl on both north-and south-facing slopes. We measured diameter at breast height (DBH) of each mature individual of all tree species (DBH ≥10 cm), and recorded the number of seedlings (DBH <10 cm, height <30 cm) and saplings (DBH <10 cm, height >30 cm). We also measured soil moisture and soil pH, estimated canopy cover, and recorded slope and altitude in each quadrat. For all species together and for several species individually, tree density, seedling density, sapling density and tree basal area were found to decrease with elevation on both north and south aspects. This trend is largely explained by the progressively harsher environment at higher elevations. The north-facing slopes in our study area have denser forests than the south-facing slopes, the density of all size classes (seedling, sapling and mature plants) and basal area being greater on the northern aspects. These aspect-wide differences are attributable to the stark difference in soil moisture between northern and southern aspects, which is in turn due to the difference in insolation. Irrespective of elevation and aspect, all the forests studied are regenerating, as indicated by inverse J-shaped density-diameter curves. The elevational pattern of seedling and sapling abundance is explained only by elevation. Whereas other variables (e.g., canopy) are considered to have an important influence on seed germination and seedling establishment, they turn out not to be significant predictors of density of seedlings and saplings. This failure to identify a relationship is probably due to our use of non-parametric test (tree regression analysis) that we used to establish the relationship between density and its potential explanatory variables or due to our selection of 1 standard error rule yielding sub-optimal models for regression trees.

Nordic Journal of Botany, 2013

ABSTRACT Abeliophyllum, a monotypic endemic genus of Oleaceae, resembles Forsythia in various mor... more ABSTRACT Abeliophyllum, a monotypic endemic genus of Oleaceae, resembles Forsythia in various morphological characters, but its phylogenetic position is disputed and no embryological study of the genus has been carried out. We investigated more than 40 embryological characters of Abeliophyllum, compared them with previous information on Oleaceae, and discusses its phylogenetic relationships. Abeliophyllum is similar to other genera of Oleaceae in many embryological features, having some distinct features such as the mode of anther wall formation, formation of a nucellar cap, and formation of obturator and hypostase. The basic type of anther wall development and formation of a nucellar cap have not previously been reported in Oleaceae. In addition, differentiation of the obturator and formation of hypostase are not reported in the previously investigated genera of the family. Compared with close relatives, the seed coat structure of Abeliophyllum resembles Forsythia more than Fontanesia and supports existing molecular data which place Abeliophyllum as the sister group of Forsythia.

Mountain Research and Development, 2007

Journal of Plant Research, 2014

The comparative study on leaf anatomy and stomata structures of six genera of Taxaceae s. l. was ... more The comparative study on leaf anatomy and stomata structures of six genera of Taxaceae s. l. was conducted. Leaf anatomical structures were very comparable to each other in tissue shape and their arrangements. Taxus, Austrotaxus, and Pseudotaxus have no foliar resin canal, whereas Amentotaxus, Cephalotaxus, and Torreya have a single resin canal located below the vascular bundle. Among them, Torreya was unique with thick-walled, almost round sclerenchymatous epidermal cells. In addition, Amentotaxus and Torreya were comprised of some fiber cells around the vascular bundle. Also, Amentotaxus resembled Cephalotaxus harringtonia and its var. nana because they have discontinuous fibrous hypodermis. However, C. fortunei lacked the same kind of cells. Stomata were arranged in two stomatal bands separated by a mid-vein. The most unique stomatal structure was of Taxus with papillose accessory cells forming stomatal apparatus and of Torreya with deeply seated stomata covered with a special filament structure. Some morphological and molecular studies have already been discussed for the alternative classification of taxad genera into different minor families. The present study is also similar to these hypotheses because each genus has their own individuality in anatomical structure and stomata morphology. In conclusion, these differences in leaf and stomata morphology neither strongly support the two tribes in Taxaceae nor fairly recognize the monogeneric family, Cephalotaxaceae. Rather, it might support an alternative classification of taxad genera in different minor families or a single family Taxaceae including Cephalotaxus. In this study, we would prefer the latter one because there is no clear reason to separate Cephalotaxus from the rest genera of Taxaceae. Therefore, Taxaceae should be redefined with broad circumscriptions including Cephalotaxus.

International Journal of Botany, 2012

International Journal of …, 2008

A quantitative vegetative analysis of Juniperus indica forest was done along an altitudinal gradi... more A quantitative vegetative analysis of Juniperus indica forest was done along an altitudinal gradient on southern aspect of U-shaped Manang valley (3300-4000 m asl), during May-October 2004. The study area was divided in to three elevation ranges: 3300-...

Korean Journal of Plant Taxonomy, Mar 1, 2010

(English) The Illam district, situated in the extreme North Eastern part (Latitude 26.58 N and 87... more (English) The Illam district, situated in the extreme North Eastern part (Latitude 26.58 N and 87.58 E Longitude) of Nepal, is a hot spot for floral diversity. The study of wild edible plants of this region was an attempt to highlight the types of wild flowering plants found there and mode of use by the people of the Illam hills. In this respect, a survey of natural resources of some of the representative regions of the district was undertaken and more than 74 major varieties of plant species were found to be used frequently by the ...