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Gender plasticity uncovers multiple sexual morphs in natural populations of Cedrus deodara (Roxb.) G. Don

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Ecological Processes 2021年第1期10卷 459-469页

作者： Vinod Prasad Khanduri Arun Sukumaran chandra mohan sharma Department of Forestry College of ForestryVCSG Uttarakhand University of Horticulture and ForestryRanichauriTehri GarhwalUttarakhand 249199India Present Address:State Farming Corporation of Kerala Chithalvetty EstateKalanjoor KollamKeralaIndia.

Background:The expression of gender in gymnosperms is challenging because the extent of variability in gender segregations in tree crowns and selection pressure of nature can modify the gender through ***:An in-depth investigation on spatial segregation of genders in tree crowns and sex expression of a total of 500 trees in five different natural populations of Cedrus deodara was carried out and verified the occurrence of subdioecious(co-existence of male,female,and monoecious)genders in ***:Five different sexual morphs were apparent among the 500 selected individuals as(1)pure male(M):bearing only male strobili in the whole crown with 22.2%;(2)pure female(F):bearing only female strobili in the whole crown with 12.4%;(3)mixed-monoecious(MM):bearing both male and female strobili with 13.6%;(4)predominantly female(PF)with 25.6%;and(5)predominantly male(PM)with 26.2%.The occurrence of multiple sexual morphs resulted from the complex selection pressure,which increased the stability of the *** segregation of genders in crown layers deemed to increase the fitness that may be a mechanism for accelerating *** results of the study suggest that the subdioecious gender expression in *** is evolved through the monoecy–paradioecy *** production of male strobili revealed non-significant effect of tree sizes whereas a significant effect was observed for the production of female *** study established that the total pollen and seed outputs in *** changed frequently according to gender ***:The size of the tree,resource availability,sex allocation,plant architecture,gender segregation in crowns,and habitat conditions are the prominent causes for gender plasticity.

关键词： Gender Sex expression Gender segregation Strobili Pre-fertilisation Monoecy Dioecy

Pollinator-mediated self-pollination and reproductive assurance in an isolated tree of Magnolia grandiflora L.

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Ecological Processes 2020年第1期9卷 517-525页

作者： Arun Sukumaran Vinod Prasad Khanduri chandra mohan sharma College of Forestry VCSG Uttarakhand University of Horticulture and ForestryRanichauriTehri GarhwalUttarakhand 249199India

Background:The ability to produce seeds when pollinators or potential mates are scarce is one of the principal advantages of self-pollination in flowering ***,the role of pollinators mediating self-pollination to ensure seed set when pollen or potential mates are limited has received less *** study examined the reproductive consequences and involvement of pollinators in assuring seed set in an isolated tree of Magnolia grandiflora,a predominantly outcrossing ***:We tested various aspects of reproduction such as flower density,floral rewards,stigma receptivity,pollinator abundance and behaviour,fruit set and seed set,in two successive reproductive years(2015-2016).Results:Flowers of *** possess a suite of traits facilitating pollinator-mediated self-pollination(PMS),although the chances of autonomous self-pollination are reduced due to herkogamy,spatial separation of anther and *** mean pollen production/flower was 5,152,289±285,094 with a pollen-to-ovule ratio of 39430±*** found a significant positive correlation between number of visits and seed production for bees(r=0.5099,p=0.0007)and beetles(r=0.7159,p=0.00001),indicating these are effective at *** was a significant negative correlation for thrips(r=-0.3206,p=0.044)and no correlation for flies or *** percent fruit set was 100%and the seed set per ovule ranged between 19 and 20%.Conclusions:PMS will guarantee reproductive assurance and mitigate the effect of reduced mates or pollen limitation which is expected to increase the fecundity and establishment of individual trees in geographically isolated locations.

关键词： Pollinator-mediated self-pollination Magnolia grandiflora Autonomous self-pollination Pollinator behaviour Reproductive assurance

Reproductive biology of Cornus capitata Wall. ex Roxb.: a native species in East Asia

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Journal of Forestry Research 2019年第6期30卷 2039-2050页

作者： Vinod Prasad Khanduri Arun Sukumaran chandra mohan sharma College of Forestry VCSG Uttarakhand University of Horticulture and Forestry

The reproductive biology of Cornus capitata was studied in detail from June 2014 to October 2015 in Tehri Garhwal, Uttarakhand, western Himalaya, India and elucidated floral morphology, confirming autogamy, geitonogamy, and xenogamy. A new inflorescence ball formed each year with developing fruits that were initiated the previous year; thus reproduction is a continuous cycle. The total pollen production within a tree ranged between 4.0 × 10~7 and 9.3 × 10~7. Anthesis peaked between 08:00 and 10:00. There was significant effect of micro-environmental condition on anthesis(F = 243.8, p = 3.01). A significant positive relationship between the number of lateral shoots and total inflorescence showed that the inflorescence production in C. capitate depends largely on the number of lateral shoots. Time and concentration of various solutions significantly affected pollen germination(time: F = 5.39, p = 0.002; concentration: F = 1.40,p = 0.234). Anthophora bees and thrips were observed as the main pollinators. There was a significant difference in seed set between natural and obligate self-pollination(t = 11.84, p = 1.99). Significant effect was also observed on fruit size(t = 8.88, p = 2.09) between open and shaded conditions. SEM micrographs of pollen grains showed that the shape of dehydrated pollen grains differed greatly due to variations in the rate of dehydration among pollen grains within the anther. Seed germination was observed only in quality seed derived from open pollination, supporting xenogamy in C. capitata. Findings of the present study will be of immense value in formulating effective conservation measures for the species in wild habitats.

关键词： Floral development Pollen production Pollination Pollinators Reproductive success SEM analysis

Productivity status of traditional agrisilviculture system on northern and southern aspects in mid-hill situation of Garhwal Himalaya,India

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Journal of Forestry Research 2009年第2期20卷 137-143页

作者： Arvind Bijalwan chandra mohan sharma V. K. Sah College of Forestry and Environment Allahabad Agricultural Institute- Deemed University Department of Botany H.N.B. Garhwal University Department of Forest Ecology College of Forestry and Hill Agriculture G. B. Pant University of Agriculture and Technology

The productivity of traditional agrisilviculture system(agricultural crops + trees) was investigated in the northern and southern aspects of mid-hill situation in Garhwal Himalaya, Uttarakhand, India during the 2004?2006.A total of 19 tree species were studied in both northern and southern aspects, out of which 17 tree species were selected in northern aspect and 12 tree species in southern aspect for phytosociological characteristic analysis of trees in agrisilvicultural *** most dominant tree species are Grewia optiva, Celtis australis and Melia azedarach and successively grown under traditional agrisilviculture *** results show that the annual productivity of all tree species was 3 775 kg·ha-1·a-1 in northern aspect(site-N) and 3 101 kg·ha-1·a-1 in southern aspect(site-S).*** had the highest productivity in both site-N and site-S among the tree species, followed by ***, Quercus leucotrichophora and *** dominant agricultural crops were Eleusine coracana in summer cereals, Phaseolus vulgaris in summer pulses-oilseeds and Triticum aestivum in the winter season in the *** average biological productivity of agricultural crops in northern aspect was about 16% higher than that in southern aspect under traditional agrisilviculture *** sole agricultural crop productivity(without trees) in northern aspect was also higher than that in southern *** obvious difference in annual productivity of trees and agriculture crops was observed between northern aspect and southern *** overall productivity in traditional agrisilviculture system(crop + tree) was 24%(in northern aspect) and 21%(in southern aspect) higher than that in sole cropping system.

关键词： traditional agrisilviculture system sole agricultural system productivity phytosociology sole crop importance value index

The effects of disturbance on forest structure and diversity at different altitudes in Garhwal Himalaya

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生态学杂志 2009年第3期28卷 424-432页

作者： Munesh KUMAR chandra mohan sharma Govind Singh RA JWAR Department of Forestry Henwati Nandan BahugunaGarhwal University Department of Botany Henwati Nandan BahugunaGarhwal University Department of Botany Government Post Graduate College

The effects of disturbance on forest structure and diversity along an altitudinal gradient in the temperate,sub-tropical,and tropical regions of Garhwal Himalaya were *** region was further categorized into undisturbed(UD),mildly disturbed(MD),and highly disturbed(HD)sites on the basis of magnitude of disturbance in these *** UD sites of temperate,sub-tropical and tropical regions,Quercus leucotrichophora,Anogeissus latifolia and Holoptelea integrifolia were the dominant tree species *** highest values of tree density(1028 ind·hm-2)and total basal cover at breast height(31.70 m2 ·hm-2)were recorded for UD site of temperate region,whereas maximum species diversity(3.128)and equitability(14.09)values were observed for HD site of tropical *** structure and composition of the forests were greatly affected by the degree of disturbance.

关键词：植物多样性生物结构森林生态系统

Effect of pre-soaking and pre-chilling treatments on seed germination of Pinus roxburghii provenances from western Himalaya, India

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Journal of Forestry Research 2009年第4期20卷 323-330,I0005页

作者： Sunil Kumar Ghildiyal chandra mohan sharma Vinod Prasad Khanduri Department of Botany HNB Garhwal University Department of Forestry Mizoram University

After subjecting the seeds to GA3 and H2O2 treatments for 24 h and chilling at 2-3℃ for a period of 15 days, we conducted the seed germination tests for 21 different seed sources ofPinns roxburghii from western-central Himalaya under laboratory conditions at various temperatures viz., 20℃, 25℃ and 30℃ inside a seed germinator. The results reveal that the soaking of seeds in H2O2 （1% v/v） and GA3 （ 10 mg.L^-1） solutions manifested 82.39% and 78.19% germination, respectively whereas untreated seeds exhibited 70.79% average germination. Both GA3 and H2O2 treatments caused an appreciable shortening of the germination period by 8 days and 10 days, respectively. Moist-chilling did improve the rate and percentage of germination when germinated at 20℃ over 21 days; however total germination was not affected at temperatures 25℃ and 30℃, Although the seeds of P. roxburghii germinate well due to lack of dor- mancy, the increasing demand for large quantities of seeds of P. roxburghii for reforestation programmes make pre-sowing treatments useful in improving the rate and percentage of gemaination.

关键词： seed germination seed sources provenances temperature GA3 H2O2 chilling chit pine Pinus roxburghii Himalaya

Beneficial effects of cold-moist stratification on seed germination be- haviors of Abies pindrow and Picea smithiana

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Journal of Forestry Research 2008年第2期19卷 125-130页

作者： Balbir Singh Rawat Vinod Prasad Khanduri chandra mohan sharma Department of Forestry HNB Garhwal University Post Box-76 Srinagar Garhwal-246174 (Uttaranchal) India Department of Forestry Mizoram University Aizawl-796001 Mizoram India

A study was conducted to evaluate the effect of GA3, moist-chilling and temperature on seed germination ofAbies pindrow and Picea smithiana from five different provenances. Seeds were soaked in GA3 （10 mg·L^-1） for 24 h, then chilled at 3-5℃ for 15 days. Four temperature regimes viz. 10℃, 15℃, 20℃ and 25℃ were used for stimulating seed germination. Results showed that soaking and chilling significantly increased germination percentage. The germination percentage was highest at 10℃. Overall results showed that soaking seeds in GA3 （10 mg·L^-1） for 24 h, moist chilling for 15 days, and germinating at 10℃ produced an effective germination in both the species studied. The statistical analysis of the data proclaimed significant effect of treatment, temperature, provenance and treatment with temperature interactions on seed germination.

关键词： stratification provenance seed germination GA3 silver fir spruce

Land-use,biomass and carbon estimation in dry tropical forest of Chhattisgarh region in India using satellite remote sensing and GIS

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Journal of Forestry Research 2010年第2期21卷 161-170,I0004,I0005页

作者： Arvind Bijalwan S.L.Swamy chandra mohan sharma Neeraj Kumar sharma A.K.Tiwari College of Forestry and Environment Allahabad Agricultrual Institute-Deemed University Department of Forestry indira Gandhi Agricultural University Department of Botany H.N.B.Garhwal University Jharkhand Space Application Centre Regional Remote Sensing Service Centre IIRS

A study was conducted to characterize the land use,biomass and carbon status of dry tropical forest in Raipur district of Chhattisgarh,India using satellite remote sensing data and GIS techniques in the year of *** main forest types observed in the area are Teak forest,mixed forest,degraded forest and Sal mixed *** aspect and slope of the sites influenced the forest vegetation types,biomass and carbon storage in the different *** standing volume,above ground biomass and carbon storage varied from 35.59 to 64.31 m^3·ha^-1,45.94 to 78.31 Mg·ha^-1,and 22.97 to 33.27 Mg·ha^-1,respectively among different forest *** highest volumes,above ground biomass and carbon storage per hectare were found in the mixed forest and lowest in the degraded *** total standing carbon present in the entire study area was 78170.72 Mg in mixed forest,81656.91 Mg in Teak forest,7833.23 Mg in degraded forest and 7470.45 Mg in Sal mixed forest,*** study shows that dry tropical forests of the studied area in Chhattisgarh are in growing stage and have strong potential for carbon sequestration.

关键词： biomass carbon storage aspect slope

Green synthesis of biocompatible gold nanoparticles using Fagopyrum esculentum leaf extract

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Frontiers of Materials Science 2011年第4期5卷 379-387页

作者： Punuri Jayasekhar BABU Pragya sharma mohan chandra KALITA Utpal BORA Biotech Hub Centre for the Environment Indian Institute of Technology Guwahati Guwahati Assam-781039 India Biomaterials and Tissue Engineering Laboratory Department of Biotechnology Indian Institute of Technology Guwahati Guwahati Assam-781039 India Department of Biotechnology Gauhati University Guwahati Assam-781039 India

This report describes the use of ethnolic extract of Fagopyrum esculentum leaves for the synthesis of gold nanoparticles. UV-visible spectroscopy analysis indicated the successful formation of gold nanoparticles. The synthesized nanoparticles were characterized by transmission electron microscopy （TEM）, high resolution TEM （HRTEM） and were found to be spherical, hexagonal and triangular in shape with an average size of 8.3 nm. The crystalline nature of the gold nanoparticles was confirmed from *** diffraction （XRD） and selected-area electron diffraction （SAED） patterns. Fourier transform infrared （FT-IR） and *** X-ray analysis （EDX） suggested the presence of organic biomolecules on the surface of the gold nanoparticles. Cytotoxicity tests against human HeLa, MCF-7 and IMR-32 cancer cell lines revealed that the gold nanoparticles were non-toxic and thus have potential for use in various biomedical applications.

关键词： biomaterials crystal growth electron microscopy Fourier transforminfrared spectroscopy adsorption