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Variation in cone and seed characters in blue pine (Pinus wallichiana) across natural distribution in western Himalayas 被引量:8
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作者 Ombir Singh Manisha Thapliyal 《Journal of Forestry Research》 CAS CSCD 2012年第2期235-239,共5页
We analyzed 17 seed sources (seed stands) ofPinus wallichiana for variations present in cone and seed characters, scattered over natural distribution in north-west Himalayan states (Uttarakhand and Himachal Pradesh... We analyzed 17 seed sources (seed stands) ofPinus wallichiana for variations present in cone and seed characters, scattered over natural distribution in north-west Himalayan states (Uttarakhand and Himachal Pradesh) of India. The significant variations were observed in cone weight, cone length, cone width, seed length, seed width, seed weight, seed germination, radicle length, and plumule length among different seed sources of the species. Significant positive correlation between seed weight, cone weight and cone width showed that seed weight in the species depend more on the cone size. Seed germination was also positively correlated with seed weight, cone weight and radicle length in the study. The estimates of variability with regard to genetic parameters for seed weight, seed germination, cone length, cone width, cone weight showed wide range of variation in the study. Seed weight showed high heritability values coupled with maximum genetic gain. Traits with such values indicate presence of good amount of heritable additive components and are under strong genetic control. The findings of the study revealed that seed sources expressed both phenotypic and genotypic differences in the seed and cone traits which might be due to the differences in genetic make up of various seed sources and environmental factors i,e. genotypic and environmental interaction, The study suggests that the seed weight should be given the top priority for the further improvement of this species. 展开更多
关键词 seed sources seed traits HERITABILITY genetic gain improve-ment.
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Variability in cone,seed and seedling characteristics of Pinus kesiya Royle ex.Gordon 被引量:6
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作者 Ombir Singh Satyam Bordoloi N.Mahanta 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第2期331-337,共7页
Investigations were made to determine the nature and extent of variations present for 10 morphological characters of cone,seed and seedlings of 17 plus trees(PTs)of Pinus kesiya growing in eastern Himalayas(Meghala... Investigations were made to determine the nature and extent of variations present for 10 morphological characters of cone,seed and seedlings of 17 plus trees(PTs)of Pinus kesiya growing in eastern Himalayas(Meghalaya state) of India.The significant variations has been observed in cone weight,cone length,cone diameter,seed length,seed diameter,seed weight,number of seeds per cone,seed germination,seedling height and seedling collar diameter among different PTs of the species.Significant positive correlation(p / 0.01) between seed weight,cone length and cone diameter showed that seed weight in P.kesiya depend more on the cone size.Seed germination is found positively correlated(p / 0.01) with seed weight,seed diameter,cone size and number of seeds per cone in the study.Among geographical factors,latitude and altitude are found positively correlated(p / 0.05) with cone weight and seed diameter,respectively.The genetic parameters for seed,cone and seedlings of PTs of P.kesiya also showed a wide range of variability in terms of variance,coefficient of variability,broad sense heritability,genetic advance and genetic gain.Seed weight,seeds per cone and seedling diameter showed high heritability values([75) coupled with maximum genetic gain.Traits with such values indicate the presence of good amount of heritable additive components and are under strong genetic control.The findings of the study revealed that PTs expressed both phenotypic and genotypic differences in the seed,cone and seedling characters,which may be attributed to the differences in genetic makeup of various PTs and environmental factors i.e.genotypic and environmental interaction.The presence of high variability in P.kesiya PTs for different characters provide further opportunities to improve the population in subsequent generations so as to establish this species as an important timber tree to be grown on less fertile and degraded soils in its distributional ranges. 展开更多
关键词 Plus trees Seed traits HERITABILITY Genetic gain Improvement
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Variability in permeability and integrity of cell membrane and depletion of food reserves in neem(Azadirachta indica) seeds from trees of different age classes 被引量:4
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作者 evendra Kumar Dhruv Kumar Mishra 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第1期147-153,共7页
We quantified cell membrane permeability (electrical conduc-tivity-EC, water soluble sugar-WSS, and amino acids-AA) and integrity (phospholipids,α-tocopherol and lipid peroxidation) along with food reserve deteri... We quantified cell membrane permeability (electrical conduc-tivity-EC, water soluble sugar-WSS, and amino acids-AA) and integrity (phospholipids,α-tocopherol and lipid peroxidation) along with food reserve deterioration (total proteins, total sugar, and total starch) of neem seeds collected from various mother tree age classes and stored for 65 days in airtight plastic containers at ambient room temperature (35±5°C). Results show that the activities were higher in fresh seeds (EC 267.56-2950.01 μS/g, WSS 19.96-19.48 mg/g and AA 5.40-5.35 mg/g) and declined with increasing duration of storage period (EC 153.37-195.17 μS/g, WSS 3.13-4.17 mg/g and AA 4.29-4.49 mg/g after 35 days and EC 144.02-161.56 μS/g, WSS 2.06-2.40 mg/g and AA 3.98-4.27 mg/g after 65 days of storage). Phospholipids andα-tocopherol were higher in fresh seed (0.073-0.093 OD at 710 nm and 0.080-0.105 OD, respectively) and declined as storage duration in-creased (0.033-0.042 OD at 710 nm and 00.0010-0.0020 OD, respec-tively). Dead seeds showed reduced amounts of phospholipids and minimum activity ofα- tocopherol (antioxidants). The level of MDA was lower in fresh seeds (0.0066-0.0087 OD at 600-535 nm) and increased as storage duration increased (0.0248-0.0268 OD after 65 days of stor-age). The higher amount of MDA indicated that seeds died due to rancid-ity of the oil inside the seed. Neem seed cake was assessed for deteriora-tion of food reserves (total proteins, total sugar, and total starch), concen-trations of which were higher in fresh seed and declined as storage dura-tion increased. Germination was higher in fresh seeds and after 65 days, no germination was received perhaps due to deterioration of biochemi-cals in seeds. Patterns of seed deterioration were similar across all seed lots. 展开更多
关键词 PHOSPHOLIPIDS Α-TOCOPHEROL Lipid peroxidation Azadirachta indica
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Multi-temporal forest cover dynamics in Kashmir Himalayan region for assessing deforestation and forest degradation in the context of REDD+ policy 被引量:2
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作者 Akhlaq Amin WANI Pawan Kumar JOSHI +1 位作者 Ombir SINGH Sumera SHAFI 《Journal of Mountain Science》 SCIE CSCD 2016年第8期1431-1441,共11页
The role of forests is being actively considered under the agenda of REDD+(Reducing Emissions from Deforestation and Forest Degradation plus) aimed at reducing emissions related to changes in forest cover and forest q... The role of forests is being actively considered under the agenda of REDD+(Reducing Emissions from Deforestation and Forest Degradation plus) aimed at reducing emissions related to changes in forest cover and forest quality. Forests in general have undergone negative changes in the past in the form of deforestation and degradation, while in some countries positive changes are reported in the form of conservation, sustainable management of forests and enhancement of carbon stock. The present study in the Kashmir Himalayan forests is an effort to assess historical forest cover changes that took place from 1980 to 2009 and to predict the same for 2030 on the basis of past trend using geospatial modeling approach. Landsat data(Multispectral Scanner(MSS),Thematic Mapper(TM) and Enhanced Thematic Mapper(ETM+)) was used for the years 1980, 1990 and(2001, 2009) respectively and change detection analysis between the dates was performed. The maps generated were validated through ground truthing. The study area(3375.62 km^2) from 1980-2009 has uffered deforestation and forest degradation of about 126 km^2 and 139.02 km^2 respectively which can be claimed under negative options of REDD+, while as the area that experienced no change(1514 km^2) can be claimed under conservation. A small area(23.31 km^2) observed as positive change can be claimed under positive options. The projected estimates of forest cover for 2030 showed increased deforestation and forest degradation on the basis of trend analysis using Cellular Automata(CA) Markov modeling. Despite the fact that country as a whole has registered a net positive change in the past few decades, but there are regions like Kashmir region of western Himalaya which have constantly undergoing deforestation as well as degradation in the past few decades. 展开更多
关键词 森林覆盖率 喜马拉雅地区 森林退化 森林砍伐 动态评估 喀什 LANDSAT SCANNER
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Variability in seed traits and genetic divergence in a clonal seed orchard of Dalbergia sissoo Roxb. 被引量:1
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作者 Ombir singh Altaf Hussain Sofi 《Journal of Forestry Research》 CAS CSCD 2012年第1期109-114,共6页
The variations in seed and pod traits, genetic superiority and genetic divergence were evaluated for a Clonal Seed Orchard (CSO) of Dalbergia sissoo Roxb. at Bithmera, India consisting of 20 clones from different ag... The variations in seed and pod traits, genetic superiority and genetic divergence were evaluated for a Clonal Seed Orchard (CSO) of Dalbergia sissoo Roxb. at Bithmera, India consisting of 20 clones from different agro-climatic conditions of four northern states (Uttar Pradesh, Uttarakhand, Haryana and Rajasthan). The seeds and pods of various clones in the orchard exhibited significant variability in size, weight and other characters. Significant positive correlations were observed between seed length and seed width (p〈0.05), seed length and sccd thickness (p〈0.01), seed length and seed weight (p〈0.01), seed thickness and seed weight (p〈0.01), seed length and germination value (p〈0.05). The ge- netic parameters for seed and pod traits also showed a wide range of variations in the orchard. Heritability values were found to be over 50 percent for most of ~e seed and pod traits. Seed weight, seed length and seed thickness showed high heritability values coupled with maximum genetic gain for these characters. Ward's minimum variance dendrogram of clones of D. sissoo showed three distinct clusters; cluster I was the largest with 12 better clones whereas cluster 2 and 3 consisting of seven moderate clones and one poor clone, respectively. Mean cluster values showed sufficient variation among the clusters for seed weight, germina- tion value and seed length. The possible hybridization between best clones of cluster I to the disease resistant clone of cluster 2 (resistant against deadly Gandoderma lucidum root rot disease of D. sissoo) is also suggested for further breeding programmes of the species. The deploy- ment of clone 194 (better performed and disease resistant) is also rec- ommended in future plantation programmes of D. sissoo in northern India. 展开更多
关键词 CLONES Dalbergia sissoo DIVERGENCE seed traits VARIABILITY
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印度热带干旱地区Tecomella undulata林木胸径-树高关系模型评价(英文) 被引量:1
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作者 Vindhya Prasad Tewari 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第4期255-260,共6页
通过搜集和观测印度拉贾斯坦邦高温干旱区纯林和间伐林分内树高和直径数据,完善和比较了4种广义直径-高度关系公式。实验数据包括1540个胸径和树高观测值,采自年龄结构和密度均有差异的蓄积林的样地。通过非线性最小二乘回归方程和不同... 通过搜集和观测印度拉贾斯坦邦高温干旱区纯林和间伐林分内树高和直径数据,完善和比较了4种广义直径-高度关系公式。实验数据包括1540个胸径和树高观测值,采自年龄结构和密度均有差异的蓄积林的样地。通过非线性最小二乘回归方程和不同的统计标准测试四个公式的性能。这些公式利用一组独立的直径-高度观测值(854个)验证(拟合阶段具有相同系数值)公式。结果表明,公式4(Hui and Gadow函数)对拟合数据和验证数据的表现最好。 展开更多
关键词 沙漠地带 印度 种植物 高度 树直径
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印度热带干旱地区沙漠柚木(Tecomel la undulata)同龄林极限林分密度与基面积模型(英文)
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作者 Vindhya Prasad Tewari 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第1期13-18,I0001,共7页
对用于评价印度拉贾斯坦邦热带干旱区沙漠柚木极限林分密度的公式进行了研究。对5个不同密度的林分基面积预测模型进行测试和比较,这些模型属非线性生长函数的轨迹不变量代数差形式。这些模型可根据林分变量,如优势高/公顷、立木数/公顷... 对用于评价印度拉贾斯坦邦热带干旱区沙漠柚木极限林分密度的公式进行了研究。对5个不同密度的林分基面积预测模型进行测试和比较,这些模型属非线性生长函数的轨迹不变量代数差形式。这些模型可根据林分变量,如优势高/公顷、立木数/公顷,预测林分基面积,还可用于评估不同造林方案。利用所收集的22块样地的数据建立模型。使用各种可能的树龄数据结构,用定性和定量标准比较了这些替代模型。使用Akaike信息准则差异统计来分析各种模型的预测能力。结果表明:Hui和Gadow提出的模型预测效果最好,推荐在本研究区域内使用该模型来预测沙漠柚木林分基面积。但是,此模型并未使用间伐林分数据,因此,不能准确地预测林木有明显自然死亡的林分基面积。图3表4参28。 展开更多
关键词 模型评价 轨迹不变量代数差生长函数 潜在密度 定性和定量标准 拉贾斯坦邦
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