Agarwood Production in Gyrinops walla (Walla patta) Myths and Reality

Gyrinops walla is recorded only in the wet and intermediate zones of Sri Lanka and veryrarely in southwest India. Recently G. walla became famous in Sri Lanka due to smugglingefforts to extract a valuable resinous product known as Agarwood which is produced as aself-defence mechanism of certain species of family Thymalaeaceae. Most of the species ofAquilaria and a few species of Gyrinops, Aetoxylon and Gonystylus of the above family arecapable of producing agarwood.The process of Agarwood oleo-resin production is the tree’s response to injury of its first lineof defence, formation of phloem callus tissue, is inhibited from forming over the injury. TheAgarwood resin is highly sought after for religious, medical, ceremonial and domesticactivities by Asian Buddhists and Moslems. A large demand is also seen in Southeast Asia,Middle East, United States and Europe for perfume manufacturing.Several sesquiterpenes, chromone derivatives, sesquiterpene furanoids, tetradecanoic acidand pentadecanoic acid are contained in Agarwood resins and the sweet aroma of the woodcomes from sesquiterpene compounds. The research conducted so far revealed a strongsimilarity of the above compounds between G. walla and that of the commercially Agarwoodproducing Aquilaria species.According to the recent information, G. walla smuggling has been conducted in Sri Lanka fora long time. The highest single amount which was made ready to export was 13,489 kgrecorded in May 2013. Although agarwood production quantities using G. walla in Sri Lankahas not been properly recorded in the past, according to the data obtained from Sri Lankapolice and customs, over 17,500 kg have been harvested in the last 12 months.However, most of the illegally felled trees had not produce Agarwood resins as the formationhas to be artificially induced. Even the Agarwood has formed due to injuries, it would havebeen in minute scale because artificial resin induction was never practised in Sri Lanka.Unfortunately, the officials who valued the smuggled G. walla timber gave an unacceptablyhigh value and therefore people disastrously felled the trees growing in the wild andhomegardens expecting high incomes. Finally a massacre of trees was started and it did notprovide expected incomes.It should be known that G. walla trees do not produce Agarwood under natural conditions.Therefore until the current researches are completed to identify the best methods to formAgarwood in this species, unnecessary harvesting should be stopped. Awareness programmeswith the Government assistance is highly useful in this task. Otherwise no trees will be leftwhen the resin formation methods are identified.

Endophytic Fungal Species in Tropical Trees: A Review

Pathogenic fungi are common in forest ecosystems which cause diseases and sometimes death of plants, while some fungi live inside trees harmlessly without causing issues. Sometimes, plants benefit from the presence of those endophytic fungi, such as gaining resistance to environmental stresses, protection from harmful pathogens etc. Numerous studies have been conducted on such relationships between endophytic fungi and short-term agricultural crops. However, such studies are rare in the literature on tropical tree species which bear timber and non-timber values. This study illustrates the studies conducted on endophytic fungi in tropical trees and explores the potential use of such fungi for obtaining benefits

Prediction of Stem Volume, Biomass and Carbon Using Age for Eucalyptus grandis in Nuwara Eliya and Badulla Districts

Forest trees act as carbon sinks and the main stem of the trees contribute most to the carbonstorage. Since Eucalyptus grandis has been extensively planted by both government andprivate sectors in the upcountry wet zone of Sri Lanka, this study attempted to predict thevolume, biomass and carbon content of the main stem of this species with age. In order toobtain a wider geographical coverage in data collection, 30 even-aged Eucalyptus grandismonoculture plantations were selected from Nuwara Eliya and Badulla Forest Divisions. Ageof those plantations varied from 7 to 40 years. Radom sampling of 0.02 ha plot size was usedfor data collection. Diameter at breast height and total height were measured from thesampled trees and a core sample was obtained from the stem for the determination of biomassand carbon amounts. Stem volume was estimated by using the model v = 0.3648(g * h) builtby Subasinghe in 2001 for the same species. Stem biomass and carbon amounts of the stemwere estimated by converting biomass and carbon contents of the extracted core samples ofknown volumes. Walkley-Black method was used for carbon content determination and thetree age was obtained from the plantation records available in the Sri Lanka ForestDepartment. Non-linear regression models were then built by using GENSTAT software topredict the selected variables using tree age. Both exponential and logistic curves were fittedto the data and model evaluation was done by the R2 values and the fitted line plots.According to the results, the stem biomass of the average tree varied from 110.8 kg at age 7to 1,095.4 at age 40. Stem carbon content varied from 68.7 kg at age 7 to 679.4 kg at age 40.When compared with the exponential models, logistic models showed poor performances andthe finally selected models for predicting dbh, height and stem volume with age weredbh = 17.83×1.028age, h = 20.09×1.019age, v = 0.264×1.066age. The R2 values for the selectedmodels were 79.1%, 84.0% and 80.1% respectively. The selected stem biomass and stemcarbon prediction models were BMstem = 108.3×1.059age, Cstem = 69.9×1.059age and those twomodels had R2 of 78.7% and 82.1% respectively. The fitted line plots too indicate very goodfits of all the selected models.

PREDICTION OF STEM VOLUME OF ALSTONIA MACROPHYLLA GROWING AS EVEN-AGED MONOCULTURES USING DIAMETER AT BREAST HEIGHT AND TOTAL HEIGHT

A growth model to predict the stem volume of Alstonia macrophylla was constructed in this study using data collected from 23 plantations from Galle, Matara, Ratnapura and Kalutara districts. Trees own variables were mainly used as explanatory variables in this study and in addition, site quality indices were also tested. At the preliminary analysis, two different site quality types were identified for the selected plantations. Therefore, first, each site quality data set was separately fitted to the theoretical models developed in this study. The selected models indicated a high modelling efficiency and a negligible bias. Although the possibility of using a common model for both site types was tested, results proved that it was not possible. Therefore it was decided to recommend two models (same structure with different sets of statistical parameters) for two site types for the field use  with the help of a given guideline to identify the plantations grown in two site types

Data Dissemination in Forestry Sector: Need, Constraints and Trends

One of the main constraints involved with research and situation analysis in forestry sector is the lack of re-measured data over a long period of time. Since the forest dynamics and tree growth takes such a long time to provide valuable insight, the data gathered in a short time period is mostly not useful. Further long-term data measured at regular intervals to detect such changes is not feasible without an intervention of a dedicate institute or group of institutes so that they can implement a formal system to collect required data and disseminate in effective manner in a selected platform. Due to the rapid change of technology, data disseminated via printed form become less popular at present. Further, raw data cannot be provided in bulk via those methods. Therefore web-based data dissemination systems, especially web portals became very much popular among the present generations. In addition to the ease of data storage, there are many advantages of having portals such as data upload, data filtering etc. However, if the portals are poorly maintained or if those do not successfully cater the user requirements, the popularity will decline. This paper discusses about the different users of forestry sector data, characteristics of good data dissemination systems, problems faced by the users in data availability and different methods of data dissemination. In addition, advantages and disadvantages of web-based data dissemination systems, especially web portals are also discussed in detail.Keywords: web portal, public access to data, stakeholder coordination, improved communicatio

Native Floral Species for Watershed Restoration and Enrichment in Sri Lanka

Sri Lanka faces frequent floods and land degradation almost frequently which is aggravated by high rainfall intensities and poor land management practices. This problem is common in most areas because about 90% of the total landmass of Sri Lanka comes within river watersheds. Though Sri Lanka is one of the richest countries in floral diversity, the recognition of native tree and plant species which are suitable for restoration of degraded lands in all three climate zones has not been done before. Therefore this study was conducted to fill that gap which is essential for land managers in both private and public sectors. With literature survey, field observations and expert interviews this study identified and developed a database of suitable native tree and plant species for restoration of watersheds and their conservation status, growth parameters, and the uses of each species.Keywords: watershed planting, tree selection, enrichment, site degradatio

Morphological and Oil Content Variation of Curry Leaves in Sri Lanka

Murraya koenigii, commonly known as curry leaf in English is native to south Asian region including India and Sri Lanka. It is a perennial shrub or small tree commonly found in forests and cultivated in homegardens for its aromatic leaves andmedicinal properties. The volatile oil extracted from leaves also bear insect repellent and anti-microbial properties. According to the local knowledge, people in Sri Lanka use various plants with similar morphology as curry leaves, especially for cooking. Therefore, this research is aimed to identify different types of curry leaf plants available in Sri Lanka and to analyse morphology, oil content and its constituents. For this purpose,a survey was first conducted by interviewing subject experts to identify different types of curry leaf plants available in the country. This survey identified 3 main species together with a few varieties. The identified species are Murraya koenigii (karapincha), Micromelum minutum (wal karapincha) and Clausena indica (mee-gon karapincha) and the varieties are beheth karapincha, dam karapincha and malu karapincha. Morphology of mature leaflets and rachis about 15 cm below the shoot apex was examined and herbarium sheets were prepared for morphologically different samples. Hydro-distillation was conducted for 100 g of leaves with 1.2 L of water for 5 hours to extract leaf oil. GC-MS instrumentwas used for oil constituent analysis. Morphologically curry leaves have bipinnately compound, spirally arranged leaves with length of 15-20 cm and leaflets with length of 3-4 cm and width of 1-2 cm. However, variations were also observed depending on the speciesand variety, for example, the leaf length was about 6 cm in beheth karapincha while 25 cm in M. koenigii. Leaves were usually green, but it was purple in colour for dam karapincha. C. indica had the highest oil yield (0.50%±0.24%) among tested species and varieties. M. koenigii recorded the highest oil yield from Dehiattakandiya (0.40%±0.06%) and the lowest from Melsiripura (0.13%±0.04%). According to the preliminary analysis conducted by GC-MS, the highest number of constituents was recorded by M. koenigii of Horowpothana (151 constituents) followed by M. minutum of Yagirala (79), C. indica of Rasnayakapura (75), M. koenigii of Yagirala (73), beheth karapincha of Panangala (44). Further studies are currently underway covering a wider geographical area to arrive proper conclusions.Keywords: Curry leaves, Leaf morphology, Oil content, Oil constituents, Murraya koenigi

Comparison of Chemical Composition of Biologically Induced Agarwood Resins in Aquilaria crassna

Agarwood is a highly valuable aromatic substance which is derived from the heartwood of Aquilaria and Gyrinops species of family Thymalaeaceae. Healthy heartwood of the above species is relatively pale in colour and low in density. Those species produce dark, dense and highly fragrant aromatic agarwood resin as a defense mechanism to protect the internal stem tissues from pathogenic invasions. Fungal species can be used to induce agarwood formation of agarwood in artificial manner. This study tested the quality of the agarwood formed in A. crassna induced by nine different fungal species. Spore suspensions of Aspergillus, Botryosphaeria, Colletotrichem, Fusarium and Nigrospora which were previously identified from naturally formed agarwood tissues of A. crassna and G. walla were used as inocula to induce agarwood formation. Inoculations were made at two opposite points of 10 year old A. crassna tree stems with three replicates. Agarwood tissues formed due to above fungal species were collected after six months of inoculation. Agarwood resin content was analysed by solvent extraction and constituents were identified by GC-MS method. According to the results, the average oil contents varied from 0.86±0.03% to 5.57±0.24%. The highest resin content was produced by F. solani while the lowest content was produced by C. gleosporoides. According to GC-MS analysis, the highest number of constituents was formed due to A. sojae (16) followed by F. solani (15) and Botryosphaeria sp3 (12). Among the constituents identified, the most common ones were valencene, eudesmol, caryophyllene, cadinene, selinene, 10-epi-elemol and ermarphillane. Trans-α-bergamotene, eudesma-3,7(11)-diene and elemene was the least common constituent. Ermarphillane, 10-epi-elemol and eudesmol were present respectively in the highest amounts in agarwood resins formed by all fungal species. Based on the results, F. solani can be considered the most suitable species to form high quality agarwood resins.Keywords: Aquilaria crassna, Fungal species, Fusarium solani, Agarwood resin, Chemical compositio

Presence of Actinomycetes in agarwood tissues of Aquilaria crassna: A preliminary study

Agarwood is a valuable resin produced inside certain tree species of the family Thymalaeaceae distributed in the Asian region. Agarwood production occurs as a defense mechanism when the trees are under physical or biological stresses. However, the formation of agarwood resins in significant extractable quantities due to natural stress conditions is rare; therefore, the farmers use various methods to induce its formation artificially. Certain fungal species such as Fusarium and Aspergillus become more popular among them to produce high-quality agarwood. However, studies are rare on using other microbial organisms such as Actinomycetes, which exhibit properties of both bacteria and fungi. Among the agarwood-producing species, Aquilaria crassna is one of Asia's most commonly planted species for agarwood production. This species was introduced to Sri Lanka in 2012 for mid and lower elevations of the wet zone. Due to the lack of studies on agarwood resin formation by non-fungal microbial methods, the present study attempted to identify the presence of Actinomycetes species in agarwood resinous tissues of A. crassna. Agarwood resinous tissue samples were collected from four plantations in the wet zone of the country. Surface sterilized, small sized tissues were placed on starch casein agar medium and incubated at room temperature for ten days. Using the morphological and microscopic characteristics, it was possible to identify Nocardia, Psuedonocardia, and three Streptomyces species with varying abundance. The species level should be confirmed using molecular analysis, and their potential for agarwood resin formation inducement should be tested by re-inoculating to the healthy A. crassna trees

Biomass Partitioning and Accumulation in Tectona grandis (Teak) at Young Stage

Forest biomass is considered to have a large potential for temporary and long-term carbonstorage as biomass. Enhancement of biomass increase via forest plantation establishment canbe considered as an effective method of mitigation of atmospheric carbon dioxide. However,due to the difficulty of measuring the below ground biomass accumulation, most of the treeand forest related biomass studies have been conducted on the above ground components ofthe trees. Therefore the present study was conducted to identify the biomass accumulationover the age and its partition in above and below ground segments of young teak trees bydestructive sampling.Teak trees of 55, 67, 79, 91 and 103 months growing in a single plantation in Puttlam wasselected for this reason. Three trees of each age were randomly selected and carefullyuprooted with the minimum damage to the roots. Then each tree was separated into mainstem, primary, secondary and tertiary branches and roots and the weights were measured.Representative samples of each segment of the tree were oven dried at 72° C for three days.Then the biomass of each segment was calculated.The average total tree biomass increased from 28.430 to 79.760 kg from 55 to 103 months.Comparatively, the highest biomass was recorded in the main stem (63.5%) followed byprimary branches (15.7%). The third highest biomass was recorded from the roots (11.7%)and the lowest biomass was recorded in tertiary branches (3.6%). A strong exponentialrelationship was observed between the tree age and whole tree biomass increase with the R2of 97.7%. It further revealed that the biomass increase of teak is rising with a rapid rate evenat the age of 10 years.Keywords: Tree biomass, Biomass partition, Tea