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1.
Significant cocoa production in the municipality of Waslala, Nicaragua, began in 1961. Since the 1980s, its economic importance to rural smallholders increased, and the region now contributes more than 50% of national cocoa bean production. This research aimed to assist local farmers to develop production of high-value cocoa based on optimal use of cacao biodiversity. Using microsatellite markers, the allelic composition and genetic structure of cacao was assessed from 44 representative plantings and two unmanaged trees. The population at Waslala consists of only three putative founder genotype spectra (lineages). Two (B and R) were introduced during the past 50 years and occur in >95% of all trees sampled, indicating high rates of outcrossing. Based on intermediate allelic diversity, there was large farm-to-farm multilocus genotypic variation. GIS analysis revealed unequal distribution of the genotype spectra, with R being frequent within a 2 km corridor along roads, and B at more remote sites with lower precipitation. The third lineage, Y, was detected in the two forest trees. For explaining the spatial stratification of the genotype spectra, both human intervention and a combination of management and selection driven by environmental conditions, appear responsible. Genotypes of individual trees were highly diverse across plantings, thus enabling selection for farm-specific qualities. On-farm populations can currently be most clearly recognized by the degree of the contribution of the three genotype spectra. Of two possible strategies for future development of cacao in Waslala, i.e. introducing more unrelated germplasm, or working with existing on-site diversity, the latter seems most appropriate. Superior genotypes could be selected by their specific composite genotype spectra as soon as associations with desired quality traits are established, and clonally multiplied. The two Y trees from the forest share a single multilocus genotype, possibly representing the Mayan, 'ancient Criollo' cacao.  相似文献   

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3.
Neighbor Trees: Shade, Intercropping, and Cacao in Ecuador   总被引:2,自引:0,他引:2  
Previous studies have shown that shade trees in cacao and coffee are important habitats for inter-American migratory birds. A survey of 21 cacao farmers along the northern, central, and southern Pacific Coast of Ecuador found that shade trees are associated with unirrigated, traditional cacao varieties and low levels of chemical inputs. Farmers stressed the importance of shade for managing soil moisture and soil fertility, and for managing some weeds and diseases. Most of the shade trees were not wild forest trees, but had been planted and protected by the farm families. Many other trees are intercropped with cacao for economic reasons, not related to shade. Chocolate manufacturers, consumers, and environmental activists can encourage farmers to maintain shade canopies by paying a premium for the traditional, shade-loving, high-quality aromatic cocoa varieties.  相似文献   

4.
There are, at the present time, effectively no long-range, ongoing programs in any tropical country of the western hemisphere dedicated to the improvement of cacao (Theobroma cacao, Sterculiaceae). While some effort is currently made to obtain new acquisitions of cacao cultivars exhibiting desirable characteristics and to maintain genepools of these trees, there are few data from field trials to prove and substantiate these qualities. In addition, there is a growing concern regarding the disparities between predicted yields of cacao trees through the use of “hybrid” seed and from actual production under field conditions. This has stimulated an awareness of the current inadequate understanding of the genetics of cacao and the lack of comprehension as to which cultivars, under distinct ecological conditions, are precocious, resistant to disease, or heavy bearing, or indeed demonstrate those traits vital to the success of farming programs adapted to today’s market conditions. This paper examines the events that have led to the current status of selection, development, and breeding of cacao. Alternative approaches are suggested.  相似文献   

5.
A recent debate has contrasted two conservation strategies in agricultural landscapes; either “land sparing” farm development combining intensive production practices with forest set-asides, or “wildlife-friendly” farming with greater on-farm habitat value but lower yields. We argue that in established mosaic landscapes including old cacao production regions where natural forest has already been reduced to relatively small fragments, a combination of both strategies is needed to conserve biodiversity. After reviewing the evidence for the insufficiency of either strategy alone if applied to such landscapes, the paper focuses on the cacao production landscape of southern Bahia, Brazil, once the world’s second largest cacao producer. Here, small remaining areas of Atlantic Forest are embedded in a matrix dominated by traditional cacao agroforests, resulting in a landscape mosaic that has proven favorable to the conservation of the region’s high biodiversity. We show that current land use dynamics and public policies pose threats but also offer opportunities to conservation and describe a three-pronged landscape conservation strategy, consisting of (i) expansion of the protected areas system, (ii) promotion of productive yet biodiversity-friendly cacao farming practices, and (iii) assistance to land users to implement legally mandated on-farm reserves and voluntary private reserves. We discuss recent experiences concerning the implementation of this strategy, discuss likely future scenarios, and reflect on the applicability of the Bahian experience to biodiversity rich cacao production regions elsewhere in the tropics.  相似文献   

6.
Mangroves and brackishwater pond culture in the Philippines   总被引:1,自引:1,他引:0  
Around 50% of mangrove loss in the Philippines can be traced to brackishwater pond construction. The decrease in mangroves from 450 000 ha in 1920 to 132 500 ha in 1990 has been accompanied by expansion of culture ponds to 223 000 ha in 1990. The history of fishpond development in the country includes a government-sponsored fishpond boom in the 1950-g and 1960s, the proconservation decade of the 1970s followed by a shrimp fever in the 1980s. Production from brackisshwater ponds has increased from 15 900 mt worth P7.6 million in 1938 to 267 000 mt valued at P6.5 billion in 1990. On the other hand, the maximum valuation of over $11 000 ha–1 yr–1 for unmanaged and managed mangrove forests makes them economically on par with the most profitable pond farming systems. The loss of mangrove systems and their varied goods and services is the single most important consequence of brackishwater pond culture in the Philippines. Moreover, intensive shrimp farming is associated with other ecological and socioeconomic effects such as pollution of coastal waters and decline in domestic food crops. New legislation and enforcement of existing laws, conservation of remaining mangroves, massive rehabilitation of denuded mangrove areas, and promotion of sustainable aquaculture and fisheries are recommended.  相似文献   

7.
The uses, perceptions, and economic significance of cacao have radically changed in the past 25 years among the Mopan Maya in southern Belize. Cacao was once perceived as a ceremonial crop with little cash value. Over the past 25 years though, cacao has become the most important cash crop grown by the Mopan Maya. The Mopan Maya grow organic cacao that has allowed them to tap into a specialized, high-end chocolate market. However, the emergence of cacao as an important cash crop has altered traditional uses and created conflicts in villages where increasing acreage of reservation lands are planted with cacao, thereby assigning a commercial value to previously communal lands.  相似文献   

8.
周晴  潘晓云 《植物生态学报》2014,38(10):1093-1098
为了探究凤眼蓝(别名凤眼莲, Eichhornia crassipes)入侵中国南部基塘区的主要原因, 对历史文献与档案资料进行了综合分析, 结果表明: 凤眼蓝在中国大陆的出现早于1930年。1911年后, 凤眼蓝曾入侵浙江省杭嘉湖平原水网河道。凤眼蓝也是1911年以来珠江三角洲地区十分常见的水生植物。1911-1980年, 基塘农业是浙江省的杭嘉湖地区和广东省珠江三角洲地区的典型农业经营模式, 凤眼蓝在这两个地区都曾被用作有机肥。20世纪50年代末至70年代, 长江流域曾推广凤眼蓝栽培技术, 对凤眼蓝进行了大规模的养植, 但1950-1980年的广积肥运动控制了凤眼蓝的繁殖速度和规模。1980年以来, 基塘地区成为长江三角洲和珠江三角洲城镇化与工业化快速发展的区域, 传统的循环农业经营模式普遍被废弃, 同时, 基塘区河网湿地水文生态环境的改变是凤眼蓝入侵中国南部基塘区的主要原因。  相似文献   

9.
In 1904 the American Consul General at Hankow, China sent seed of tung (Aleurites fordii) to the U. S. Dept. of Agriculture at Chico, California. One tree planted near Tallahassee, Florida in 1907, produced a crop of fruit in 1913, from which the first 2.2 gallons of American tung oil were extracted. By 1930, nearly 8000 acres of tung orchard had been planted in Florida, and extensive plantings were made in Mississippi and Louisiana. By 1938 there were approximately 200,000 acres of tung orchards in the southeastern United States. Today the tung industry is hard-pressed to meet competition from substitutes and from importations. American tung growers are striving to get their industry on a sound economic basis by lowering their cost of production and widening the market for tung oil.  相似文献   

10.
The tropical tree crop Theobroma cacao L. is grown commercially for its beans, which are used in the production of cocoa butter and chocolate. Although the upper Amazon region is the center of origin for cacao, 70% of the world??s supply of cacao beans currently comes from small farms in West Africa. While cacao breeding programs in producer nations are the source of improved planting material, modern marker-based breeding is difficult to perform due to the lack of genotyping facilities in these countries. While DNA extraction can be routinely performed, the equipment needed to analyze simple sequence repeats (SSRs) is seldom available, forcing the outsourcing of genotyping to foreign laboratories and delaying the breeding process. We describe a 5?? nuclease (TaqMan)-based single nucleotide polymorphism (SNP) assay for genotyping cacao plants under conditions similar to those found in most cacao-producing areas. The assay was tested under field conditions by planting open pollinated seeds of seven pods from four different maternal plants. The resulting 171 seedlings were successfully genotyped with 18 SNP markers representing 12 loci. The ability to use temperature-stable reagents and rapid DNA extraction methods is also explored. Additionally, by examining the seedling genotypes for the SNP markers and 14 additional SSR markers, we investigated whether seeds in a pod are the result of single or multiple pollination events. This simple, effective method of genotyping cacao seedlings in the field should allow for more efficient resource management of seed gardens and is currently being implemented in Ghana.  相似文献   

11.
Cacao beans are composed of cacao nibs and germs. Although numerous chemical and physiological studies on cacao nib compounds have been reported, there is little information on cacao germ compounds. We therefore analyzed an extract from the cacao germ, and found two compounds that were specific to the germ. One of these two compounds was identified as the new glycosylated abscisic acid metabolite, dihydrophaseic acid-4'-O-6″-(β-ribofuranosyl)-β-glucopyranoside, and the other as the known compound, dihydrophaseic acid-4'-O-β-D-glucopyranoside.  相似文献   

12.
Microflora of raw cacao beans   总被引:1,自引:0,他引:1  
Whole non-moldy cacao beans from 14 sources cultured on Czapek's agar with six percent NaCl yielded species ofAspergillus glaucus group,Mucor pusillus and unidentified yeast and bacteria. The average number of bacterial colonies from the 14 sources of non-moldy cacao beans was 32.7 million per gram. The average number of colonies of filamentous fungi in dilution cultures was 57,000 colonies per gram. Yeast colonies were present in the amount of 15.8 million colonies per gram. The moldy beans analyzed contained fungi and bacterial counts in the billions; also, yeast was not isolated from the moldy samples.Paper Number 3170 of the Journal Series of the North Carolina State University Agricultural Experiment Station, Raleigh, North Carolina 27607.  相似文献   

13.
Cacao beans must be subjected to fermentation before they are used in making chocolate, and their commercial value is related to a proper procedure. Saccharomyces rosei, Hansenula anomala, Pichia fermentans, Pichia membranaefaciens, and Trichosporon cutaneum were found in fermenting cacao beans. All species isolated during the investigation grew on cacao pulp, but only S. rosei, H. anomala, and P. fermentans exhibited fermenting capacity on the sugars of cacao pulp. Species of the genus Saccharomyces were identified as the agents responsible for the alcoholic phase of the cacao fermentation.  相似文献   

14.
斜纹夜蛾发生规律和预测预报新方法   总被引:18,自引:0,他引:18  
斜纹夜蛾是浙江省慈溪市蔬菜、大豆的重要害虫。 90年代以来已有 5年大发生 ,其原因为主害作物大豆、蔬菜面积大幅度增加 ,气候条件适宜 ,繁殖量大 ;其危害夏秋蔬菜损失达 65.6% ,危害秋大豆造成减产 2 2 .5%~ 77.5% ;应用斜纹夜蛾性诱剂进行预测预报 ,较黑光灯、糖醋液、树枝把诱蛾灵敏、清晰、专一。  相似文献   

15.
Tropical secondary forest and agroforestry systems have been identified as important refuges for the local species diversity of birds and other animal groups, but little is known about the importance of these systems for terrestrial herbs. In particular, few studies report how the conversion from tropical forest to technified cacao plantation affects the species richness and the community structure of herbs. We conducted surveys in 43 cacao plantations along the border of the Lore Lindu National Park in Central Sulawesi, ranging from agroforests to technified cacao, categorizing the plantations as rustic cacao, planted shade cacao, and technified cacao. We recorded 91 herb species. Of the 74 species determined to species level, 21 were also found in natural forests, while 53 were recorded only in agricultural habitats. Araceae was the most forest‐dependent plant family while Asteraceae included the highest number of nonforest species. Overall, the presence of forest species was confined to moderately intensively managed rustic and planted shaded plantations. Distance from the forest, which has been identified as a crucial parameter for the diversity and composition of other taxa in cacao agroforests, only played a minimal role for herbs. Our study suggests that native forest herbs maybe more vulnerable to forest conversion than animal groups. The intensification of cacao plantation management increases the presence of weedy species to the detriment of native forest species.  相似文献   

16.
Fermentation of Theobroma cacao (cacao) seeds is an absolute requirement for the full development of chocolate flavor precursors. An adequate aeration of the fermenting cacao seed mass is a fundamental prerequisite for a satisfactory fermentation. Here, we evaluated whether a controlled inoculation of cacao seed fermentation using a Kluyveromyces marxianus hybrid yeast strain, with an increased pectinolytic activity, would improve an earlier liquid drainage ('sweatings') from the fermentation mass, developing a superior final product quality. Inoculation with K. marxianus increased by one third the volume of drained liquid and affected the microorganism population structure during fermentation, which was detectable up to the end of the process. Introduction of the hybrid yeast affected the profile of total seed protein degradation evaluated by polyacrylamide gel electrophoresis, with improved seed protein degradation, and reduction of titrable acidity. Sensorial evaluation of the chocolate obtained from beans fermented with the K. marxianus inoculation was more accepted by analysts in comparison with the one from cocoa obtained through natural fermentation. The increase in mass aeration during the first 24 h seemed to be fundamental for the improvement of fermentation quality, demonstrating the potential application of this improved hybrid yeast strain with superior exogenous pectinolytic activity.  相似文献   

17.
An examination of population trends for northern shrimp (Pandalus borealis) and its key predators off eastern Newfoundland and Labrador provided the basis for investigating predator-prey relationships within an ecosystem that experienced major changes in species composition during the 1980s and 1990s. Populations of several demersal fish species, known to feed on northern shrimp, declined to historically low levels by the early 1990s and remained depressed thereafter. Some declines were precipitous from the late 1980s to early 1990s, coincident with an increase in shrimp. Populations of other important predator species increased throughout the 1990s along with shrimp. Lacking representative estimates of shrimp consumption, the net effect on predation mortality was unquantifiable and it was not possible to demonstrate with certainty that the major increase in shrimp biomass that occurred throughout the 1990s resulted from a concomitant reduction in predation mortality. Factors (and their interactions) relevant to the dynamics of shrimp populations include the effects of ocean climate, predation, competition, as well as commercial harvesting.  相似文献   

18.
The seeds of Theobroma cacao (cacao) are the source of cocoa, the raw material for the multi-billion dollar chocolate industry. Cacao’s two most important traits are its unique seed storage triglyceride (cocoa butter) and the flavor of its fermented beans (chocolate). The genome of T. cacao is being sequenced, and to expand the utility of the genome sequence to the improvement of cacao, we are evaluating Theobroma grandiflorum, the closest economically important species of Theobroma for its potential use in a comparative genomic study. T. grandiflorum differs from cacao in important agronomic traits such as flavor of the fermented beans, disease resistance to witches’ broom and abscission of mature fruits. By comparing genomic sequences and analyzing viable inter-specific hybrids, we hope to identify the key genes that regulate cacao’s most important traits. We have investigated the utility in T. grandiflorum of three types of markers (microsatellite markers, single-strand conformational polymorphism markers and single nucleotide polymorphism (SNP) markers) developed in cacao. Through sequencing of amplicons of 12 diverse individuals of both cacao and T. grandiflorum, we have identified new intra- and inter-specific SNPs. Two markers which had no overlap of alleles between the species were used to genotype putative inter-specific hybrid seedlings. Sequence conservation was significant and species-specific differences numerous enough to suggest that comparative genomics of T. grandiflorum and T. cacao will be useful in elucidating the genetic differences that lead to a variety of important agronomic trait differences.  相似文献   

19.
The cacao bean harvest from the relatively under developed tropical tree cacao (Theobroma cacao L.) is subject to high losses in potential production due to pests and diseases. To discover and understand the stability of putative natural resistance mechanisms in this commodity crop, essential for chocolate production, we undertook a gene-discovery program and demonstrated its use in gene-expression arrays. Sequencing and assembling bean and leaf cDNA library inserts produced a unique contig set of 1,380 members. High-quality annotation of this gene set using Blast and MetaFam produced annotation for 75% of the contigs and allowed us to identify the types of gene expressed in cacao beans and leaves. Microarrays were constructed using amplified inserts of the uni-gene set and challenged with bean and leaf RNA from five cacao varieties. The microarray performed well across the five randomly chosen cacao genotypes and did not show a bias towards either leaf or bean tissues. This demonstrates that the gene sequences are useful for microarray analysis across cacao genotypes and tissue types. The array results, when compared with real-time PCR results for selected genes, showed a correlation with differential gene-expression patterns.We intend that the resultant DNA sequences and molecular microarray platform will help the cacao community to understand the basis, likely stability and pathotype resistance range of candidate cacao plants.  相似文献   

20.
Seaweed (Kappaphycus spp.) farming has been practised in Malaysia since the late 1970s following government policy incentives (training and farming inputs). However, numerous governance, economic, environmental, technological and sociocultural challenges have limited the industry from achieving its full potential. The Seaweed Cluster Project (SCP) was introduced in 2012 to address some of these challenges. We sought to evaluate the effectiveness of the SCP in delivering its central objectives of increasing seaweed production, optimising the farming area, improving seaweed quality and farming efficiency, raising farmers’ income, and reducing the environmental impact of seaweed farming. Community and industry perceptions of the SCP were obtained from seven communities using a mixed-methods approach based on face-to-face semi-structured interviews, focus group discussions, household surveys, observation and secondary data. Views on the SCP outcomes were generally negative, including low take-up rates by indigenous people, poor stakeholder participation in decision-making, limited acceptance of new technologies, economic vulnerability, a complex marketing system, and low social cohesion of seaweed farming communities. Positive perceptions included recognition that the SCP confers high social status upon a community, reduces operating costs, and facilitates the production of certified seaweed. The SCP’s problems are linked to poor multi-level governance, weak market mechanisms and unintegrated community development. The study concludes with five recommendations to improve the SCP: promote the participation of indigenous people; legalise existing migrant farmers; strengthen local seaweed cooperative organisations; provide entrepreneurship skills to farmers; and fully integrate stakeholders into decision-making.  相似文献   

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