Rubber ( Heveabrasiliensis ) is one of the major economically important estate crops and generates the third largest export income of Sri Lanka. Rubber plantations established mostly in Wet Zone and certain regions in Intermediate Zone and the cultivated areas are known as traditional areas. However, presently rubber cultivation has been expanded to the dry zone of country and the cultivated areas are known as non-traditional areas. Corynesporacassiicola is the most destructive foliar pathogen of the rubber plant causing Corynespora leaf fall disease (CLFD) and the disease has caused a major devastation in rubber industry resulting in a remarkable economic loss. This study aimed to determine the variability of C. cassiicola isolates from traditional and non-traditional rubber growing areas using pathological factors. Ten isolates of C. cassiicola which had been isolated from diseased leaves of different clones grown in traditional (five isolates) and non-traditional (five isolates) areas were used for characterization. Variability in pathogenicity, temperature sensitivity, growth rate, conidia production, fungicide sensitivity to two fungicides; mancozeb and carbendazim and toxin production were examined. Data were statistically analyzed and the final analytical output revealed a statistically significant difference (p <0.05) between the isolates, but not between two geographical regions for all parameterstested except for toxin production and sensitivity to carbendazim. Though isolates of C.cassiicola show significant difference in pathological factors among isolates irrespective of geographical location, they do not behave differently in different climatic regions. Keywords: Corynesporacassiicola , CLFD, toxins, traditional and non-traditional areas
橡胶(Heveabrasiliensis)是一种重要的经济作物，是斯里兰卡第三大出口收入来源。橡胶种植园大多建立在湿润区，中间区和耕地的某些地区被称为传统地区。然而，目前橡胶种植已扩大到国家的干旱地区，栽培地区被称为非传统地区。橡胶树落叶病(Corynesporacassiicola)是橡胶树落叶病(Corynespora leaf fall disease, CLFD)最具破坏性的叶面病原菌，给橡胶工业造成了巨大的破坏和经济损失。本研究旨在利用病理因素确定传统橡胶种植区和非传统橡胶种植区分离的卡氏杆菌的变异性。从传统地区(5株)和非传统地区(5株)不同无性系的患病叶片中分离到的10株仙桃弧菌进行了鉴定。致病性、温度敏感性、生长率、分生孢子产量、杀菌剂对两种杀菌剂的敏感性差异;测定了代森锰锌和多菌灵的产毒情况。对数据进行统计分析，最终分析结果显示，菌株之间的差异有统计学意义(p <0.05)，但除毒素产量和对多菌灵的敏感性外，所有参数在两个地理区域之间均无统计学差异。尽管不同地理位置的分离株在病原菌病理因子上存在显著差异，但在不同气候区域的分离株表现并无差异。关键词:冠状菌，CLFD，毒素，传统和非传统领域
{"title":"Pathological characterization of Corynespora cassiicola isolates from traditional and non-traditional rubber growing areas","authors":"Y. L. Wijesingha, T. Fernando, K. Fernando","doi":"10.31357/JTFE.V7I2.3312","DOIUrl":"https://doi.org/10.31357/JTFE.V7I2.3312","url":null,"abstract":"Rubber ( Heveabrasiliensis ) is one of the major economically important estate crops and generates the third largest export income of Sri Lanka. Rubber plantations established mostly in Wet Zone and certain regions in Intermediate Zone and the cultivated areas are known as traditional areas. However, presently rubber cultivation has been expanded to the dry zone of country and the cultivated areas are known as non-traditional areas. Corynesporacassiicola is the most destructive foliar pathogen of the rubber plant causing Corynespora leaf fall disease (CLFD) and the disease has caused a major devastation in rubber industry resulting in a remarkable economic loss. This study aimed to determine the variability of C. cassiicola isolates from traditional and non-traditional rubber growing areas using pathological factors. Ten isolates of C. cassiicola which had been isolated from diseased leaves of different clones grown in traditional (five isolates) and non-traditional (five isolates) areas were used for characterization. Variability in pathogenicity, temperature sensitivity, growth rate, conidia production, fungicide sensitivity to two fungicides; mancozeb and carbendazim and toxin production were examined. Data were statistically analyzed and the final analytical output revealed a statistically significant difference (p <0.05) between the isolates, but not between two geographical regions for all parameterstested except for toxin production and sensitivity to carbendazim. Though isolates of C.cassiicola show significant difference in pathological factors among isolates irrespective of geographical location, they do not behave differently in different climatic regions. Keywords: Corynesporacassiicola , CLFD, toxins, traditional and non-traditional areas","PeriodicalId":17445,"journal":{"name":"Journal of Tropical Forestry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87799751","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The organic solvent extracts from the seeds of Erythrina indica were tested for their insecticidal action against Hyblaea puera, the most important defoliator pest of teak. The larvicidal activity of the petroleum ether, chloroform, methanol, ethyl alcohol, ethyl acetate, acetone and water extracts from the seeds of E. indica on the 3rd instar larvae of H. puera showed 100% mortality even with least concentration (0.25%). The ovicidal activity was exhibited by chloroform and ethyl acetate extract. Both the extracts exhibited highest egg hatch inhibition (56%) at highest concentration (2%). The least LC50 (1.15%) shows that ethyl acetate extract is better than chloroform extract (1.78). Two compounds were isolated from the ethyl acetate extract of the seeds of Erythrina indica by column chromatography. The compounds were identified using HPLC, GC MS, and NMR. Compound 1 was a mixture of linoleic acid and oleic acid. Compound 2 was a mixture of linoleic acid and oleic acid ester with a glycerol unit attached to it. Compounds 1 and 2 were biologically active and exhibited potent insecticidal activity against the 3rd instar larvae of H. puera. The result showed that Compound 2 isolated from E. indica exhibited highest mortality (72%) at concentration (0.125%). At highest concentration (0.5%) highest mortality (92%) was exhibited by Compound 2 which on comparison is on par with the Neemark (Azadirachtin) exhibiting highest mortality (100%). The study is complementary with earliar works and proves that the seeds of E. indica has immense potential to be utilized as botanical insecticide.
{"title":"Insecticidal factors from the seeds of Erythrina indica Lam against Hyblaea puera, the most serious defoliator pest of teak","authors":"B. Deepa, O. Remadevi","doi":"10.31357/JTFE.V7I1.3019","DOIUrl":"https://doi.org/10.31357/JTFE.V7I1.3019","url":null,"abstract":"The organic solvent extracts from the seeds of Erythrina indica were tested for their insecticidal action against Hyblaea puera, the most important defoliator pest of teak. The larvicidal activity of the petroleum ether, chloroform, methanol, ethyl alcohol, ethyl acetate, acetone and water extracts from the seeds of E. indica on the 3rd instar larvae of H. puera showed 100% mortality even with least concentration (0.25%). The ovicidal activity was exhibited by chloroform and ethyl acetate extract. Both the extracts exhibited highest egg hatch inhibition (56%) at highest concentration (2%). The least LC50 (1.15%) shows that ethyl acetate extract is better than chloroform extract (1.78). Two compounds were isolated from the ethyl acetate extract of the seeds of Erythrina indica by column chromatography. The compounds were identified using HPLC, GC MS, and NMR. Compound 1 was a mixture of linoleic acid and oleic acid. Compound 2 was a mixture of linoleic acid and oleic acid ester with a glycerol unit attached to it. Compounds 1 and 2 were biologically active and exhibited potent insecticidal activity against the 3rd instar larvae of H. puera. The result showed that Compound 2 isolated from E. indica exhibited highest mortality (72%) at concentration (0.125%). At highest concentration (0.5%) highest mortality (92%) was exhibited by Compound 2 which on comparison is on par with the Neemark (Azadirachtin) exhibiting highest mortality (100%). The study is complementary with earliar works and proves that the seeds of E. indica has immense potential to be utilized as botanical insecticide.","PeriodicalId":17445,"journal":{"name":"Journal of Tropical Forestry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82270327","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The crown of tree is the centre of physiological activity which gives an indication of the potential photosynthetic capacity on a tree. Though, its measurement remains a challenge in forest inventory task. The ability to predict crown diameter from stump diameter provides an effective technique of obtaining its estimate. This helps in detecting the excessive tree felling than actual requirements and wildlife suitability.The main objective of this study was to develop and test crown diameter prediction models for silvicultural management of naturally grown Parkia biglobosa within the University of Agriculture, Makurdi. Nine 100 m x 100 m temporary sample plots were established using simple random sampling method. Crown diameter and stump diameter were measured in all living P. biglobosa trees with stump diameter ≥10.0 cm. Least square method was used to convert the counted stumps into harvested crown dimension. Three linear and three non-linear models using stump diameter as the exploratory variable were developed and evaluated using the adjusted coefficient of determination (Adj.R 2 ), standard error of estimate (SEE), prediction error sum of squares (PRESS) and Akaike information criterion (AIC). The crown-stump diameter relationship was best described by the double logarithmic function with .The result showed that Crown diameter estimation was feasible even when the only information available is stump diameter.The resulting equation was tested for validation with independent data obtained from additional plots and was found to be desirable for estimating the crown diameter for Parkia biglobosa in Makurdi, Benue State, Nigeria.
树冠是生理活动的中心，反映了树木潜在的光合能力。然而，其测量仍然是森林清查任务中的一个挑战。从树桩直径预测树冠直径的能力为树冠直径的估计提供了一种有效的方法。这有助于发现过度砍伐树木，而不是实际需求和野生动物的适宜性。本研究的主要目的是在马库尔迪农业大学内开发和测试自然生长的白桦树冠直径预测模型。采用简单随机抽样法建立9个100 m × 100 m临时样地。在树桩直径≥10.0 cm的所有活树中测量树冠直径和树桩直径。利用最小二乘法将已计数树桩换算成采伐树冠尺寸。以残桩直径为探索变量，建立了3个线性和3个非线性模型，并采用调整决定系数(adj . r2)、估计标准误差(SEE)、预测误差平方和(PRESS)和Akaike信息准则(AIC)对模型进行了评价。结果表明，当树冠直径仅为树桩直径时，树冠直径的估计是可行的。用从其他样地获得的独立数据对所得方程进行了验证，结果发现该方程对于估计尼日利亚贝努埃州马库尔迪的大白桦树冠直径是理想的。
{"title":"Crown-Stump Diameter Model for Parkia biglobosa Benth. Species in Makurdi, Benue State, Nigeria","authors":"Onyekachi Chukwu, J. H. Dau, J. U. Ezenwenyi","doi":"10.31357/JTFE.V7I1.3021","DOIUrl":"https://doi.org/10.31357/JTFE.V7I1.3021","url":null,"abstract":"The crown of tree is the centre of physiological activity which gives an indication of the potential photosynthetic capacity on a tree. Though, its measurement remains a challenge in forest inventory task. The ability to predict crown diameter from stump diameter provides an effective technique of obtaining its estimate. This helps in detecting the excessive tree felling than actual requirements and wildlife suitability.The main objective of this study was to develop and test crown diameter prediction models for silvicultural management of naturally grown Parkia biglobosa within the University of Agriculture, Makurdi. Nine 100 m x 100 m temporary sample plots were established using simple random sampling method. Crown diameter and stump diameter were measured in all living P. biglobosa trees with stump diameter ≥10.0 cm. Least square method was used to convert the counted stumps into harvested crown dimension. Three linear and three non-linear models using stump diameter as the exploratory variable were developed and evaluated using the adjusted coefficient of determination (Adj.R 2 ), standard error of estimate (SEE), prediction error sum of squares (PRESS) and Akaike information criterion (AIC). The crown-stump diameter relationship was best described by the double logarithmic function with .The result showed that Crown diameter estimation was feasible even when the only information available is stump diameter.The resulting equation was tested for validation with independent data obtained from additional plots and was found to be desirable for estimating the crown diameter for Parkia biglobosa in Makurdi, Benue State, Nigeria.","PeriodicalId":17445,"journal":{"name":"Journal of Tropical Forestry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79103870","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The Indian Pangolin (Manis crassicaudata) is arguably the least studied species of all Asiatic pangolin species and, is the solitary pangolin species recorded in Sri Lanka. Growing concerns over their population decline due to poaching and trading has triggered a move to uplift Indian Pangolin to Appendix I of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). However, lack of reliable scientific information on the behavior, ecology and threats for the survival of Indian Pangolin remains a major limitation in conservation of the species. This narrative review discusses the current knowledge on Indian Pangolin with special reference to Sri Lanka, and identifies key research priorities for better conservation planning of the species.
{"title":"Pangolins (Manis crassicaudata) in Sri Lanka: A Review of Current Knowledge, Threats and Research Priorities","authors":"P. Perera, K.V.D.H.R. Karawita, M.G.T. Pabasara","doi":"10.31357/JTFE.V7I1.3018","DOIUrl":"https://doi.org/10.31357/JTFE.V7I1.3018","url":null,"abstract":"The Indian Pangolin (Manis crassicaudata) is arguably the least studied species of all Asiatic pangolin species and, is the solitary pangolin species recorded in Sri Lanka. Growing concerns over their population decline due to poaching and trading has triggered a move to uplift Indian Pangolin to Appendix I of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). However, lack of reliable scientific information on the behavior, ecology and threats for the survival of Indian Pangolin remains a major limitation in conservation of the species. This narrative review discusses the current knowledge on Indian Pangolin with special reference to Sri Lanka, and identifies key research priorities for better conservation planning of the species.","PeriodicalId":17445,"journal":{"name":"Journal of Tropical Forestry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83318898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Biomass transfer or cultivation of leguminous trees has higher eco-friendly profiles for soil nutrients restoration especially nitrogen. The research is conducted on decomposition and nitrogen release patterns of Parkia biglobosa and Albizia lebbeck leaves with nitrogen fertilizer for maize production in sudan savannah alfisol of Nigeria. Data were analysed using (ANOVA). 56 % of N in the litter bag was released the first two weeks of biomass incubation and progressively increases weeks after planting. Decomposition rate constant (KD) ranged from 9.18 to 15.07 week-1 and the rates of plant residues was higher in Albizia lebbeck than Parkia biglobosa in both seasons. Nitrogen release rate constant (KN), ranging from 7.82 to 10.81 week-1 followed a similar pattern as the rate of decomposition with Albizia lebbeck releasing the highest amount of N followed by Parkia lebbeck . The rate of decomposition increased as week increased. Incorporation of Albizia lebbeck had significantly higher effect (p < 0.05) on growth parameter and yield component compared to Parkia biglobosa . The study concluded that Albizia lebbeck decomposed and mineralized faster for crop uptake under sudan savanna conditions. The study suggests that incorporation of Albizia lebbeck and up to 40 kg N ha-1 is a better combination for soil quality improvement and maize productivity in Makera, a semi-arid environment of Nigeria.
生物量转移或种植豆科树木对土壤养分特别是氮的恢复具有更高的生态友好性。在尼日利亚的苏丹大草原alfisol进行了玉米生产中施用氮肥对大叶阔叶树(Parkia biglobosa)和大叶阔叶树(Albizia lebbeck)叶片分解和氮素释放规律的研究。数据采用方差分析(ANOVA)进行分析。凋落物袋中56%的氮素在生物量孵化前两周释放，在种植后数周逐渐增加。腐解速率常数(KD)在9.18 ~ 15.07周-1之间变化，两季合欢的腐解速率均高于白鹤柏。氮素释放速率常数(KN)在7.82 ~ 10.81周-1范围内，与分解速率规律相似，小叶合欢释氮量最高，小叶合欢次之。随着时间的增加，分解速率增加。合欢花添加量对其生长参数和产量构成的影响显著高于大叶百合(p < 0.05)。该研究得出结论，在苏丹稀树草原条件下，大菱角的分解和矿化速度更快，有利于作物吸收。该研究表明，在尼日利亚半干旱的Makera地区，Albizia lebbeck和高达40 kg N ha-1的混合施用是改善土壤质量和提高玉米生产力的较好组合。
{"title":"Decomposition and Nitrogen Release Patterns of Parkiabiglobosa and Albizialebbeck Leaves with Nitrogen Fertilizer for Maize Production in Sudan Savanna Alfisolof Nigeria","authors":"N. Oyebamiji, A. Babalola, A. Aduradola","doi":"10.31357/JTFE.V7I1.3022","DOIUrl":"https://doi.org/10.31357/JTFE.V7I1.3022","url":null,"abstract":"Biomass transfer or cultivation of leguminous trees has higher eco-friendly profiles for soil nutrients restoration especially nitrogen. The research is conducted on decomposition and nitrogen release patterns of Parkia biglobosa and Albizia lebbeck leaves with nitrogen fertilizer for maize production in sudan savannah alfisol of Nigeria. Data were analysed using (ANOVA). 56 % of N in the litter bag was released the first two weeks of biomass incubation and progressively increases weeks after planting. Decomposition rate constant (KD) ranged from 9.18 to 15.07 week-1 and the rates of plant residues was higher in Albizia lebbeck than Parkia biglobosa in both seasons. Nitrogen release rate constant (KN), ranging from 7.82 to 10.81 week-1 followed a similar pattern as the rate of decomposition with Albizia lebbeck releasing the highest amount of N followed by Parkia lebbeck . The rate of decomposition increased as week increased. Incorporation of Albizia lebbeck had significantly higher effect (p < 0.05) on growth parameter and yield component compared to Parkia biglobosa . The study concluded that Albizia lebbeck decomposed and mineralized faster for crop uptake under sudan savanna conditions. The study suggests that incorporation of Albizia lebbeck and up to 40 kg N ha-1 is a better combination for soil quality improvement and maize productivity in Makera, a semi-arid environment of Nigeria.","PeriodicalId":17445,"journal":{"name":"Journal of Tropical Forestry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89794373","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Schizophyllum commune is an edible mushroom grown on wood under natural conditions. Present study focused on cultivation of S.commune on different wood substrates since it is not commercially cultivated. A pure culture of S. commune was obtained by growing a tissue of the mushroom on Potato Dextrose Agar (PDA) medium. Spawns were produced by growing the mycelium on paddy grains. Mushroom was cultivated on sawdust of seven different wood substrates. The maximum yield was observed in sawdust of jackfruit ( Artocarpus heterophyllus ) followed by sawdust of rambutan ( Nephelium lappaceum ) and country almond ( Terminalia catappa ). A significant difference was not observed when mango ( Mangifera indica ) elephant apple ( Dillenia indica ), tulip wood tree ( Harpullia arborea ) and thungfaa ( Alstonia macrophylla ) sawdust used as substrate. The lowest yield was observed in thungfaa ( Alstonia macrophylla ) sawdust. Effect of some additives on the yield was studied and significant difference in yield was observed when rice bran and used-tea leaves used as additives. Effect of rice bran on yield was studied using different ratios of sawdust to rice bran and the highest was observed in 2:1 ratio of sawdust to rice bran. The best incubating temperature for mycelial growth on the substrate was 350C. The composition of the mushroom on a dry weight basis was; 71.4% moisture, 23.35% crude protein and 6% ash. Tested wood species are promising substrates for cultivation of S.communeas cottage industry.
{"title":"Cultivation of Schizophyllum commune mushroom on different wood substrates","authors":"P. Dasanayaka, S. Wijeyaratne","doi":"10.31357/JTFE.V7I1.3023","DOIUrl":"https://doi.org/10.31357/JTFE.V7I1.3023","url":null,"abstract":"Schizophyllum commune is an edible mushroom grown on wood under natural conditions. Present study focused on cultivation of S.commune on different wood substrates since it is not commercially cultivated. A pure culture of S. commune was obtained by growing a tissue of the mushroom on Potato Dextrose Agar (PDA) medium. Spawns were produced by growing the mycelium on paddy grains. Mushroom was cultivated on sawdust of seven different wood substrates. The maximum yield was observed in sawdust of jackfruit ( Artocarpus heterophyllus ) followed by sawdust of rambutan ( Nephelium lappaceum ) and country almond ( Terminalia catappa ). A significant difference was not observed when mango ( Mangifera indica ) elephant apple ( Dillenia indica ), tulip wood tree ( Harpullia arborea ) and thungfaa ( Alstonia macrophylla ) sawdust used as substrate. The lowest yield was observed in thungfaa ( Alstonia macrophylla ) sawdust. Effect of some additives on the yield was studied and significant difference in yield was observed when rice bran and used-tea leaves used as additives. Effect of rice bran on yield was studied using different ratios of sawdust to rice bran and the highest was observed in 2:1 ratio of sawdust to rice bran. The best incubating temperature for mycelial growth on the substrate was 350C. The composition of the mushroom on a dry weight basis was; 71.4% moisture, 23.35% crude protein and 6% ash. Tested wood species are promising substrates for cultivation of S.communeas cottage industry.","PeriodicalId":17445,"journal":{"name":"Journal of Tropical Forestry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83401073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Forests have played a vital role in the socio-economic development of Nepal with their productive, protective, and bio-esthetic functions. Stand height-diameter as well as volume estimation is very critical in forest management. This research modelled height-diameter relationship as well as tree volume for Teak ( Tectona grandis ), a well-known tropical hardwood species, in central lowland Nepal. Data was collected from a Teak plantation site in Sagarnath Forest Development Project (SFDP), Nepal. Forty-four trees representing different diameter classes were felled. The diameter at breast height (dbh) and height (H) of the trees ranged from 6.1 to 58.9 cm and 6.1 to 26.1 m, respectively. Several height-diameter models were fitted and evaluated for certain training and validating criteria. The height-diameter equation of 12H=[- 5.2544 + 6.8603A—lndbh]"> , performed well and was selected to be the best model for H prediction from dbh. Also, the volume equation of 12V=[0.3364+0.0685A—dbh+-0.097A—H] "> was selected as best fitted equation, using dbh and height as independent variables. The height in this volume equation was to be calculated from selected height-diameter equation to predict height. The equations developed are the first of their kinds officially documented for Teak species in central lowlands of Nepal.
{"title":"Modeling Height-Diameter Relationship and Volume of Teak (Tectona grandis L. F.) in Central Lowlands of Nepal","authors":"A. Koirala, A. Kizha, S. Baral","doi":"10.31357/JTFE.V7I1.3020","DOIUrl":"https://doi.org/10.31357/JTFE.V7I1.3020","url":null,"abstract":"Forests have played a vital role in the socio-economic development of Nepal with their productive, protective, and bio-esthetic functions. Stand height-diameter as well as volume estimation is very critical in forest management. This research modelled height-diameter relationship as well as tree volume for Teak ( Tectona grandis ), a well-known tropical hardwood species, in central lowland Nepal. Data was collected from a Teak plantation site in Sagarnath Forest Development Project (SFDP), Nepal. Forty-four trees representing different diameter classes were felled. The diameter at breast height (dbh) and height (H) of the trees ranged from 6.1 to 58.9 cm and 6.1 to 26.1 m, respectively. Several height-diameter models were fitted and evaluated for certain training and validating criteria. The height-diameter equation of 12H=[- 5.2544 + 6.8603A—lndbh]\"> , performed well and was selected to be the best model for H prediction from dbh. Also, the volume equation of 12V=[0.3364+0.0685A—dbh+-0.097A—H] \"> was selected as best fitted equation, using dbh and height as independent variables. The height in this volume equation was to be calculated from selected height-diameter equation to predict height. The equations developed are the first of their kinds officially documented for Teak species in central lowlands of Nepal.","PeriodicalId":17445,"journal":{"name":"Journal of Tropical Forestry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91531207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Germplasm characterization is an important link between conservation and utilization of plant genetic resources. The study was conducted to characterize randomly selected 20 finger millet germplasm accessions obtained from Plant Genetic Resource Center, Gannoruwa, Sri Lanka using morphological markers. Morphological study was carried out using Randomized Complete Block Design (RCBD) and 15 morphological markers were recorded. Analysis of variance (ANOVA) results for quantitative morphological characters revealed that all quantitative morphological characters measured differed significantly (p˂0.05) among the accessions used for the study, indicating higher levels of morphological diversity. According to the ANOVA results, days to flowering and days to maturity show high level of predictive capability while flag leaf length and number of productive tillers show comparatively low level of predictive capability. Principal component analysis indicated that morphological characters such as days to flowering, finger number and yield per plant were the important traits contributing for the overall variability implying that breeding effort on those traits can meet the targeted objective. The clustering pattern of studied finger millet accessions based on morphological markers comprised of two major clusters. Both clusters comprised of Indian accessions those conserved at PGRC, Gannoruwa and as well as Sri Lankan accessions. Results of the study suggest a considerable morphological variability, which could exist among the studied traits. Furthermore, this study revealed that the genetic diversity existed irrespective to the geographical origin. This finding justifies the importance of germplasm characterization. Keywords: Finger Millet, Morphological Markers, Germplasm Accessions, Genetic Diversity, Crop Improvement
{"title":"Assessment of Genetic Diversity of Some Finger Millet (Eleusine coracana (L.) Gaertn. Accessions Using Morphological Markers","authors":"D.V.S. Kaluthanthri, P. Dasanayaka","doi":"10.31357/JTFE.V6I2.2940","DOIUrl":"https://doi.org/10.31357/JTFE.V6I2.2940","url":null,"abstract":"Abstract Germplasm characterization is an important link between conservation and utilization of plant genetic resources. The study was conducted to characterize randomly selected 20 finger millet germplasm accessions obtained from Plant Genetic Resource Center, Gannoruwa, Sri Lanka using morphological markers. Morphological study was carried out using Randomized Complete Block Design (RCBD) and 15 morphological markers were recorded. Analysis of variance (ANOVA) results for quantitative morphological characters revealed that all quantitative morphological characters measured differed significantly (p˂0.05) among the accessions used for the study, indicating higher levels of morphological diversity. According to the ANOVA results, days to flowering and days to maturity show high level of predictive capability while flag leaf length and number of productive tillers show comparatively low level of predictive capability. Principal component analysis indicated that morphological characters such as days to flowering, finger number and yield per plant were the important traits contributing for the overall variability implying that breeding effort on those traits can meet the targeted objective. The clustering pattern of studied finger millet accessions based on morphological markers comprised of two major clusters. Both clusters comprised of Indian accessions those conserved at PGRC, Gannoruwa and as well as Sri Lankan accessions. Results of the study suggest a considerable morphological variability, which could exist among the studied traits. Furthermore, this study revealed that the genetic diversity existed irrespective to the geographical origin. This finding justifies the importance of germplasm characterization. Keywords: Finger Millet, Morphological Markers, Germplasm Accessions, Genetic Diversity, Crop Improvement","PeriodicalId":17445,"journal":{"name":"Journal of Tropical Forestry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78957067","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Protecting the right of the local community/country to use their own genetic resources available in a particular area is an important element of environmental and biodiversity conservation. However, one of the biggest biodiversity conservation challenges faced by southern peripheral countries is biopiracy and related issues. Community based ecotourism (CBET) is a well-established concept and its implementation is an important component in many regional development strategies. This research argues that though CBET which originated as a western concept has been successfully applied in number of projects, it generates biopiracy challenges in its implementation when CBET operates within different geo-political, economic and cultural contexts. This research examines such challenges to CBET initiatives in the Sinharaja world heritage site, Sri Lanka. A qualitative-inductive research methodology has principally guided this research to examine the socio-cultural and socio-economic context of biopiracy issues. A total of 293 participants have informed this research including 193 interviews. A critical discourse analysis (CDA) method is used to examine both primary qualitative data collected through participant and direct observation, interviews and secondary data. One of the main findings is that despite plans being developed at a community level, in wider context, challenges of biopiracy related to superimposed capitalism contest CBET ideologies. Superimposed capitalism results in individualistic and competitive behaviours that undermine collaborative and responsible community approach. Presently, smuggling out of Wallapatta plant (Gyrinops walla) and gathering of Spotted bowfinger gecko (Cyrtodactylus triedra) which is an endemic nocturnal reptile species have become profitable in KudawaSinharaja site and a growing number of biopirates venture into here. Local community of this site takes risks in forest genetic resources smuggling because it provides them with the means of earning much money within a short period. Regardless of all prevalent laws and regulations against bioprospecting, biopiracy, biological resource and wildlife smuggling, authorities have still failed to control these activities in this site because of the support given to bio-pirates by the local community. The research concludes that CBET is an appropriate pathway for tourism development in Sri Lanka but recognition of biopiracy issues associated with superimposed capitalism is required and needed to be addressed. A well-defined monitoring system and an effective legal framework to control adverse effects are important for achieving CBET goals while confronting biopiracy. Keywords: Biopiracy, Community Based Eco-tourism, Superimposed capitalism.
{"title":"Challenges of Biopiracy: Implementing Community Based Ecotourism (CBET) in the Sri Lankan context","authors":"H. Kumara","doi":"10.31357/JTFE.V6I2.2941","DOIUrl":"https://doi.org/10.31357/JTFE.V6I2.2941","url":null,"abstract":"Abstract Protecting the right of the local community/country to use their own genetic resources available in a particular area is an important element of environmental and biodiversity conservation. However, one of the biggest biodiversity conservation challenges faced by southern peripheral countries is biopiracy and related issues. Community based ecotourism (CBET) is a well-established concept and its implementation is an important component in many regional development strategies. This research argues that though CBET which originated as a western concept has been successfully applied in number of projects, it generates biopiracy challenges in its implementation when CBET operates within different geo-political, economic and cultural contexts. This research examines such challenges to CBET initiatives in the Sinharaja world heritage site, Sri Lanka. A qualitative-inductive research methodology has principally guided this research to examine the socio-cultural and socio-economic context of biopiracy issues. A total of 293 participants have informed this research including 193 interviews. A critical discourse analysis (CDA) method is used to examine both primary qualitative data collected through participant and direct observation, interviews and secondary data. One of the main findings is that despite plans being developed at a community level, in wider context, challenges of biopiracy related to superimposed capitalism contest CBET ideologies. Superimposed capitalism results in individualistic and competitive behaviours that undermine collaborative and responsible community approach. Presently, smuggling out of Wallapatta plant (Gyrinops walla) and gathering of Spotted bowfinger gecko (Cyrtodactylus triedra) which is an endemic nocturnal reptile species have become profitable in KudawaSinharaja site and a growing number of biopirates venture into here. Local community of this site takes risks in forest genetic resources smuggling because it provides them with the means of earning much money within a short period. Regardless of all prevalent laws and regulations against bioprospecting, biopiracy, biological resource and wildlife smuggling, authorities have still failed to control these activities in this site because of the support given to bio-pirates by the local community. The research concludes that CBET is an appropriate pathway for tourism development in Sri Lanka but recognition of biopiracy issues associated with superimposed capitalism is required and needed to be addressed. A well-defined monitoring system and an effective legal framework to control adverse effects are important for achieving CBET goals while confronting biopiracy. Keywords: Biopiracy, Community Based Eco-tourism, Superimposed capitalism.","PeriodicalId":17445,"journal":{"name":"Journal of Tropical Forestry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84994395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Landslide disaster risk reduction is presently a challenging task facing by Sri Lankan geologists. Increasing trend of population growth in Sri Lanka has adversely affected the stability of central highland due to various human activities. Among them establishment of human settlements and change in land use pattern have become a serious issue in triggering land instabilities in central highland of the country. National Building Research Oragnisation which is the main focal point in land slide disaster risk reduction in Sri Lanka has taken valuable and timely needed actions including preparation of landslide hazard zonation maps, early warnings and mitigations. Though the landslide is a geological phenomenon, it is highly interacted with human societies. Hence managing the issues arising with the landslide occurrence should be addressed with a sociological approach. This new approach is known as Socio Geological approach which is discussed here. Key words: Landslide, Geology, Socio Geology, Social Geologist
{"title":"Social Geology and Landslide Disaster Risk Reduction in Sri Lanka","authors":"P. Jayasingha","doi":"10.31357/JTFE.V6I2.2938","DOIUrl":"https://doi.org/10.31357/JTFE.V6I2.2938","url":null,"abstract":"Abstract Landslide disaster risk reduction is presently a challenging task facing by Sri Lankan geologists. Increasing trend of population growth in Sri Lanka has adversely affected the stability of central highland due to various human activities. Among them establishment of human settlements and change in land use pattern have become a serious issue in triggering land instabilities in central highland of the country. National Building Research Oragnisation which is the main focal point in land slide disaster risk reduction in Sri Lanka has taken valuable and timely needed actions including preparation of landslide hazard zonation maps, early warnings and mitigations. Though the landslide is a geological phenomenon, it is highly interacted with human societies. Hence managing the issues arising with the landslide occurrence should be addressed with a sociological approach. This new approach is known as Socio Geological approach which is discussed here. Key words: Landslide, Geology, Socio Geology, Social Geologist","PeriodicalId":17445,"journal":{"name":"Journal of Tropical Forestry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87652589","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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