6 research outputs found
History of use and trade of agarwood
Aromatics originating from the resin-infused infected wood of the Aquilaria and Gyrinops genera have distinct and valued fragrances. Resin formation occurs as a response to internal injury and/or infections in the stems of the agarwood tree. The incenses and perfumes that are produced from agarwood have been valued for centuries and used by many cultures for spiritual, opulent, and aphrodisiac purposes. Agarwood is highly revered in the seminal texts of Hinduism, Christianity, Buddhism, and Islam. As early as 1400 B.C.E., agarwood was described as a fragrant product in Sanskrit texts, and in 65 B.C.E., Dioscorides detailed several medical applications for agarwood. Knowledge of human-induced agarwood formation was recorded in China as early as 300 C.E., where it was known that cutting into a tree would lead to a color change in its internal tissues within a year of the injury as a consequence of resin development. There is historical evidence of international trade in agarwood between the producing (tropical southeastern Asia) and consuming (Middle East, India, China, and Japan) regions of the world. Agarwood has been consumed primarily as incense with the burning of wood chips directly or as an important ingredient for powdered incense blends. The aromatic qualities of agarwood are influenced by the species and variety of the two genera, geographic location, its branch, trunk and root origin, length of time since infection, and methods of harvesting and processing. The subtle but numerous variations in agarwood properties led to the development of systems for product classification and description in several consumer countries. This paper reviews the uses and trade of agarwood and its social, political, and economic significance in human history
Risk analysis and cacao pod survivorship curves to improve yield forecasting methods
Cocoa attainable yields are affected by a complex of pests and diseases in a particular agro-environment. Estimation of yield loss is critical for agronomic and economic decision-making at the farm level. For over 15 months, we monitored 1100 pods from six cocoa clones (PMCT-58, CC-137, CATIE-R1 CATIE-R4, ICS-95, and CCN-51) to assess the incidence of pests and diseases and to elucidate their survival behavior. Cocoa clones grow in a 12-year timber-based cocoa agroforestry plot (1330 cocoa plants ha-1, 100 shade trees ha-1, and 65% shade cover), in La Montaña, Turrialba, Costa Rica. Between 6-12 trees and 120-140 pods per clone of four size classes (very small – 2.5-7 cm, small – 7.1-14 cm, medium – 14.1-21 cm, and large – ≥21 cm) were tagged and measured fortnightly. Pods were selected at two vertical strata along the tree trunk (below and above 1.5 m) and grouped into three generations (rainy, transition, and dry). Competitive risk and survival analysis were performed per clone, generation, pod size class, and pod position along the tree trunk. Overall, pods reached maturity at the age of 155-165 days and were exposed to several hazards that disrupted their development. The Cox model that better described the cumulative risk during pod development included two covariables with substantial explicative power, generation, and clones. Regardless of clone and pod generation, a combination of diseases/pests accounted for about 45% to 65% of yield losses. The Kaplan-Meier survival analysis showed that pod survival was similar between generations but differed among clones within generations. Pods from CATIE-R1, CATIE-R4 and CC-137 clones showed greater survival rates than those of ICS-95, CCN-51 and PMCT-58 clones. The position of the pod along the tree trunk did not influence pod survival rates. We combined pod counting and pod survival rates calculated in this study and contrasted our yield estimations against a widely used prediction method proposed by a certification body. Overall, yield estimated using the UTZ method applied to 90-day-old pods of CATIE-R1 clone consistently overestimated yield predictions in the range of 27-45%. We proposed the combination of pod counting and pod index with a set of clone-specific discount factors; the survival rates, to reliably forecast on-farm cacao yields over time
Growth physiology and productivity of cultivated Aquilaria crassna Pierre ex Lecomte (Thymelaeaceae) in tropical Australia and its reproduction biology
Agarwood is a highly prized, resin-infused fragrant wood that has been used since early history in both secular and religious practices. Agarwood is produced mainly by species of the genus Aquilaria. The high demand for agarwood has resulted in overharvesting of the natural population. Growing Aquilaria in plantations seems a sensible approach to supply the market and meet consumer demands. Several initiatives, including the establishment of plantations, are in place in the countries of origin of the species to supply cultivated agarwood. In tropical Australia, a research plantation of Aquilaria species was established to determine the biological and commercial viability of production in an area beyond its natural range. Research was conducted in this plantation as part of this dissertation to improve our understanding of floral biology and the breeding system of Aquilaria crassna, morphological characters that differentiate species of Aquilaria, the environmental, physiological and leaf- morphological characters that influence tree growth and productivity. This knowledge (theoretical and practical) can inform methods, techniques and tools for its cultivation.
In this study, analysis of leaf outlines using elliptical Fourier descriptors was used successfully to distinguish morphological variability and discriminate between three species of Aquilaria. Flower anthesis of Aquilaria crassna occurred at evening and early morning, flowers stay open up to 3.5 days. Stigma is receptive when flowers are fully open for one day. Hand-pollination experiments showed that A. crassna is self-compatible and that there is no pollen limitation for fruit production in its new environment. Hybrids between A. crasnna and A. baillonii were possible.
Physiological and morphological leaf-traits were a useful predictor of tree productivity. Isotopic composition of carbon (δ¹³C) in leaf dry matter explained 35% of the variability in diameter. Predictors that explain growth in Aquilaria are δ¹³C, δ¹⁵N, petiole length, number of new leaves produced per week and specific leaf area. CO₂ assimilation increased linearly with PFD peaking at PFD of 1000 μmol m⁻² s⁻¹ (A(max)). Relative leaf chlorophyll content (determined using a SPAD meter and expressed as leaf greenness) correlated positively with the rate of CO₂ assimilation and % of leaf nitrogen. Leaf greenness index could be used by Aquilaria growers to maximize productivity in Aquilaria. This study provides the evidence that support the cultivation of Aquilaria spp. outside its range of distribution
Tipologías y manejo de fincas cafetaleras en los municipios de San Ramón y Matagalpa, Nicaragua
El café es el rubro más importante para los pequeños y medianos productores en América
Central y se cultiva bajo sombra como un sistema agroforestal. La diversidad en la
composición botánica, estructural y temporal de los doseles de sombra refleja los deseos y
preferencias de las familias campesinas, así se pueden encontrar gran diversidad de
cafetales dentro de un país, de una región y de la finca en diferentes momentos.
En este trabajo se estudió la gerencia, los factores biofisícos y socioeconómicos que
determinan la diversidad de la sombra en 38 fincas cafetaleras en dos municipios del
departamento de Matagalpa. Se entrevistaron a los productores y se establecieron parcelas
temporales de medición de 50*20 m en un lote de café representativo de la finca, se midió
la riqueza y abundancia de especie en el dosel de sombra, número de estratos. altura
mínima y máxima del dosel arbóreo. Las fincas se seleccionaron de la listas de productores
de la Unión Nicaragüense de Cafetaleros (lJNICAFE) y fueron clasificadas a priori de
acuerdo al tamaño de la finca en: pequeños (0. 7- 17.5 ha), medianos (17.5- 35 ha) y grandes
productores (más de 35 ha). Se estudiaron 12 fincas de los dos primeros tipos y 14 fincas
del tercer tipo de productor.
Para la caracterización de las fincas se calcularon estadísticas descriptivas y análisis de
varianza para evaluar las diferencias entre grupos de productores. La clasificación a priori
fue sometida a un análisis discriminante canónico con 25 variables cuantitativas para
determinar las variables responsables de la separación de estos grupos. Los resultados
mostraron que además del área de la finca, el número de usos de la tierra, el área del
cafetal, la riqueza de especie y el rendimiento del café, difieren entre grupos de
productores.
Se elaboró una tipología de doseles sombra mediante un análisis de componentes
principales y anáHsis discriminante canónico con 16 variables cuantitativas. Seis
componentes principales explican el 72% de la variabilidad de los datos, obteniéndose tres
grupos de sombra: 1) café con árboles de montaña y guaba o bien café con guabas y
musáceas, 2) café con sombra de maderables, guabas y musáceas y 3) café con sombra
mixta. Las variables responsables de esta clasificación fueron: altitud, porcentaje de
sombra, riqueza, densidad del dosel de sombra y la presencia de cítricos y musáceas en el
primer estrato de sombra del cafetal.
Se encontraron 62 especies en el dosel de sombra en un total de 38000 m2 muestreados, y
según su función en el cafetal 53% son especies de sombra, 21% frutales y el 8% son
maderables. Las musáceas son las especies más abundantes (121 tallos adultos ha-1
) y están
presentes en el 74% de las fincas, las guabas (Inga spp) tienen una densidad de 87 árboles
ha-1
, y se encuentran en el 95% de las fincas. Los árboles de montaña y cítricos son otros
componentes frecuentes del dosel arbóreo. La riqueza de especies de sombra es mayor en
fincas de pequeños y medianos productores que las fincas grandes.
El análisis de gerencia reflejó que los productores muestran una tendencia a diversificar la
sombra del cafetal con musáceas, cítricos y frutales si los precios del café en los próximos
cinco años siguen bajos y sin importar el tamaño de la finca. Los productores asocian
ciertas especies del dosel de sombra con la incidencia de plagas y/o enfermedades en el
cafetal y la mayoría de ellos sabe que la combinación de sombra regulada con alta
fertilización genera los más altos rendimientos.
Se concluye que la intensidad de manejo, el tamaño de la finca y el nivel socioeconómico
del caficultor son los factores que determinan la densidad y riqueza de especies de los
doseles de sombra estudiados y el amplio conocimiento de los productores en el manejo del
café les permite entender las necesidades e interacciones del cultivo con diferentes niveles
de sombra. Se recomienda estudiar la interacción entre las especies de sombra y la
incidencia de plagas y enfermedades en el cafetal, integrar en los proyectos y programas de
apoyo al sector cafetalero a los tres grupos de productores presentes en la zona motivando
la organización entre ellos y la creación de nuevas cooperativas y promover una caficultura
diversificada con especies maderables y frutales que se adapten a la zona considerando los
objetivos de cada productor
Relationship between leaf functional traits and productivity in Aquilaria crassna (Thymelaeaceae) plantations: a tool to aid in the early selection of high-yielding trees
Physiological traits are frequently used as indicators of tree productivity. Aquilaria species growing in a research planting were studied to investigate relationships between leaf-productivity traits and tree growth. Twenty-eight trees were selected to measure isotopic composition of carbon (δ13C) and nitrogen (δ15N) and monitor six leaf attributes. Trees were sampled randomly within each of four diametric classes (at 150 mm above ground level) ensuring the variability in growth of the whole population was represented. A model averaging technique based on the Akaike's information criterion was computed to identify whether leaf traits could assist in diameter prediction. Regression analysis was performed to test for relationships between carbon isotope values and diameter and leaf traits. Approximately one new leaf per week was produced by a shoot. The rate of leaf expansion was estimated as 1.45 mm day−1. The range of δ13C values in leaves of Aquilaria species was from −25.5‰ to −31‰, with an average of −28.4 ‰ (±1.5‰ SD). A moderate negative correlation (R2 = 0.357) between diameter and δ13C in leaf dry matter indicated that individuals with high intercellular CO2 concentrations (low δ13C) and associated low water-use efficiency sustained rapid growth. Analysis of the 95% confidence of best-ranked regression models indicated that the predictors that could best explain growth in Aquilaria species were δ13C, δ15N, petiole length, number of new leaves produced per week and specific leaf area. The model constructed with these variables explained 55% (R2 = 0.55) of the variability in stem diameter. This demonstrates that leaf traits can assist in the early selection of high-productivity trees in Aquilaria species