Cacao Industry Research Articles

Genome and transcriptome analysis of the latent pathogen Lasiodiplodia theobromae, an emerging threat to the cacao industry.

Lasiodiplodia theobromae (Pat.) Griffon & Maubl., a member of the family Botryosphaeriaceae, is becoming a significant threat to crops and woody plants in many parts of the world, including the major cacao growing areas. While attempting to isolate Ceratobasidium theobromae, a causal agent of vascular streak dieback (VSD), from symptomatic cacao stems, 74% of isolated fungi were Lasiodiplodia spp. Sequence-based identification of 52 putative isolates of L. theobromae indicated that diverse species of Lasiodiplodia were associated with cacao in the studied areas, and the isolates showed variation in aggressiveness when assayed using cacao leaf discs. The present study reports a 43.75 Mb de novo assembled genome of an isolate of L. theobromae from cacao. Ab initio gene prediction generated 13 061 protein-coding genes, of which 2862 are unique to L. theobromae, when compared with other closely related Botryosphaeriaceae. Transcriptome analysis revealed that 11 860 predicted genes were transcriptionally active and 1255 were more highly expressed in planta compared with cultured mycelia. The predicted genes differentially expressed during infection were mainly those involved in carbohydrate, pectin, and lignin catabolism, cytochrome P450, necrosis-inducing proteins, and putative effectors. These findings significantly expand our knowledge of the genome of L. theobromae and the genes involved in virulence and pathogenicity.

Potential of Yeasts as Biocontrol Agents of the Phytopathogen Causing Cacao Witches' Broom Disease: Is Microbial Warfare a Solution?

Plant diseases caused by fungal pathogens are responsible for major crop losses worldwide, with a significant socio-economic impact on the life of millions of people who depend on agriculture-exclusive economy. This is the case of the Witches’ Broom Disease (WBD) affecting cacao plant and fruit in South and Central America. The severity and extent of this disease is prospected to impact the growing global chocolate market in a few decades. WBD is caused by the basidiomycete fungus Moniliophthora perniciosa. The methods used to contain the fungus mainly rely on chemical fungicides, such as copper-based compounds or azoles. Not only are these highly ineffective, but also their utilization is increasingly restricted by the cacao industry, in part because it promotes fungal resistance, in part related to consumers’ health concerns and environmental awareness. Therefore, the disease is being currently tentatively controlled through phytosanitary pruning, although the full removal of infected plant material is impossible and the fungus maintains persistent inoculum in the soil, or using an endophytic fungal parasite of Moniliophthora perniciosa which production is not sustainable. The growth of Moniliophthora perniciosa was reported as being antagonized in vitro by some yeasts, which suggests that they could be used as biological control agents, suppressing the fungus multiplication and containing its spread. Concurrently, some yeast-based products are used in the protection of fruits from postharvest fungal spoilage, and the extension of diverse food products shelf-life. These successful applications suggest that yeasts can be regarded a serious alternative also in the pre-harvest management of WBD and other fungal plant diseases. Yeasts’ GRAS (Generally Recognized as Safe) nature adds to their appropriateness for field application, not raising major ecological concerns as do the present more aggressive approaches. Importantly, mitigating WBD, in a sustainable manner, would predictably have a high socioeconomic impact, contributing to diminish poverty in the cacao-producing rural communities severely affected by the disease. This review discusses the importance/advantages and the challenges that such a strategy would have for WBD containment, and presents the available information on the molecular and cellular mechanisms underlying fungi antagonism by yeasts.

First Report of Neofusicoccum parvum Causing Pod Rot on Cacao in Hawaii

HomePlant DiseaseVol. 103, No. 6First Report of Neofusicoccum parvum Causing Pod Rot on Cacao in Hawaii PreviousNext DISEASE NOTES OPENOpen Access licenseFirst Report of Neofusicoccum parvum Causing Pod Rot on Cacao in HawaiiA. S. Puig, J. P. Marelli, T. K. Matsumoto, L. M. Keith, and O. A. GutierrezA. S. Puig†Corresponding author: A. S. Puig; E-mail Address: alina.puig@ars.usda.govhttp://orcid.org/0000-0002-4662-4658Subtropical Horticultural Research Station, USDA-ARS, Miami, FL; Search for more papers by this author, J. P. MarelliMars/USDA Cocoa Laboratory, Miami, FL 33158; and Search for more papers by this author, T. K. MatsumotoDaniel K. Inouye U.S. Pacific Basin Agriculture Research Center, USDA-ARS, Hilo, HISearch for more papers by this author, L. M. Keithhttp://orcid.org/0000-0001-9974-1818Daniel K. Inouye U.S. Pacific Basin Agriculture Research Center, USDA-ARS, Hilo, HISearch for more papers by this author, and O. A. GutierrezSubtropical Horticultural Research Station, USDA-ARS, Miami, FL; Search for more papers by this authorAffiliationsAuthors and Affiliations A. S. Puig1 † J. P. Marelli2 T. K. Matsumoto3 L. M. Keith3 O. A. Gutierrez1 1Subtropical Horticultural Research Station, USDA-ARS, Miami, FL; 2Mars/USDA Cocoa Laboratory, Miami, FL 33158; and 3Daniel K. Inouye U.S. Pacific Basin Agriculture Research Center, USDA-ARS, Hilo, HI Published Online:2 Apr 2019https://doi.org/10.1094/PDIS-10-18-1719-PDNAboutSectionsSupplemental ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InRedditEmailWechat Cacao (Theobroma cacao) production is a rapidly expanding industry in Hawaii, but little information exists regarding diseases present in the area. A trip was conducted in January 2018 to assess disease problems on Hawaii Island, and pods with firm, dark brown/black lesions were observed on three of the four farms visited. Symptomatic tissue was sampled from lesion margins and inserted into a healthy, green cacao pod to maximize recovery of primary pathogens (Chee and Foong 1968). After 3 days, tissue was excised from the margins of emerging lesions, surface disinfested in 70% ethanol for 20 s, and plated on half-strength potato dextrose agar (1/2 PDA). Samples from two of the three farms yielded Phytophthora palmivora, the causal organism of black pod rot, one of the most economically important diseases of T. cacao. However, all samples from the third farm yielded a fast-growing fungus with white, aerial mycelia that turned dark gray within 4 days. Disease incidence at this farm was less than 1% (four affected trees), with all infections emanating from the peduncle. A single organism was recovered from three of the five pods sampled, with no organisms being recovered from the other two. A single representative isolate (H23) was used for molecular analysis and pathogenicity tests. DNA was extracted from 10-day-old mycelium, using the Qiagen DNeasy Plant Mini Kit, and the organism was identified by amplifying and sequencing, and by depositing in GenBank sequences of the internal transcribed spacer region (ITS; primers ITS1F/ITS4; MH449672), the translation elongation factor 1-α gene (TEF1; primers EF1-728F/EF1-986R; MH93602), and a partial sequence of the β-tubulin gene (BT; primers Bt2a/Bt2b; MH936021). BLASTN analysis identified the organism as Neofusicoccum parvum based on the ITS (99% match to MF631021), TEF1 (100% match to FJ150710), and BT (100% match to KX464975) sequences. All matching sequences were generated from organisms isolated in Hawaii from a range of host plants such as Metrosideros polymorpha, Pipturus albidus, T. cacao, and Leucadendron cultivar Safari Sunset. Owing to recent additions and reorganization of the Neofusicoccum genus, searches were limited to entries published or modified between 2012 to 2018 to ensure accuracy. To confirm pathogenicity, artificial inoculations were done using 4- × 15-cm2 pieces of immature cacao pods (clones SCA 6, EQX 3348-52, and GNV 164). Plugs of 1/2 PDA with actively growing mycelia were inoculated into wounds made with a 6-mm-diameter cork borer. A P. palmivora isolate from cacao served as a positive control and 1/2 PDA as a negative control. Four replications were inoculated with N. parvum, four with P. palmivora, and three with 1/2 PDA, and they were then kept at 25°C in the dark for 5 days. Necrotic lesions identical to those originally seen on the field-collected samples developed on all pathogen-inoculated pieces. A Welch’s ANOVA with posthoc t tests for mean separation determined that lesion radii were significantly higher for N. parvum (33.9 ± 5.8 mm) and P. palmivora (29.4 ± 1.6 mm) versus the negative control (1.3 ± 0.6 mm) (P = 0.0006). The pathogens were reisolated and identified based on colony morphology. Although N. parvum has been reported to cause dieback on ‘ōhi‘a trees in Hawaii (Hughes et al. 2018) and blueberry in Chile (Espinoza et al. 2009), to our knowledge, this is the first report of N. parvum causing pod rot on cacao. Hawaii has a burgeoning cacao industry, and thus detailed knowledge of pathogens targeting the crop is critical.The author(s) declare no conflict of interest.

Cacao quality index for cacao agroecosystems in Bahia, Brazil

ABSTRACT Brazil is increasingly committed to developing research on the quality of cacao. The objective of this work was to develop a new Cacao Quality Index (CQI) methodology with cacao industry, chocolate flavor, human health and food safety functions, and to show its results in different cacao agroecosystems from the humid region of Bahia. The typical Dystrophic Red-Yellow Argisol, in the cabruca cropping system with 35 shade trees per hectare, reached the highest CQI score. The lowest score obtained from the quality index cacao corresponded to the site characterized by the abrupt Dystrophic Red-Yellow Argisol, in the cabruca cropping system with 60 shade trees per hectare. All cropping sites obtained CQI values between 0.54 and 0.69 and were therefore classified as a regular index. The primary indicators that determined the differences between the highest and lowest CQI score were proteins, total free amino acids, simple carbohydrates (sucrose, fructose and glucose), total acidity, cadmium and barium.

Supply Chain Risk Management of The Small-Scale Industry in West Sumatera

The existing cacao industry in West Sumatera is a small scale cacao industry. One of the risks encountered in this industry is that the production does not meet the target and the specification set, resulting in the difficulties for the industry to develop. The objective of the research is to conduct a supply chain risk management in the small scale cacao industry in West Sumatera. . This research used a survey approach method. While the data collected were primary and secondary data. The supply chain management process used descriptive method and Analytic Network Process (ANP). Study on cacao industry chain supply risk source showed indicates that production risks are in the highest priority with a value of 21.78%. The marketing, financial, institutional and human resource risks have the same priority risk i.e. 19.55%. The highest priority of risk types includes the risk of availability of industrial capital, government policy, skills and personal knowledge, and production process cost, with the priority values of 0.102634; 0.101024; 0.099903; and 0.041294 respectively. An alternative risk control priority is to weaken risk (0.39191), and risk segregation (0.25798). Supply chain risk management needs to be held by weakening and segregating risks through improving product management, supply management and information management prioritized on procurement and production processes, thereby enhancing the quality and quantity of processed cocoa products on an ongoing basis. The results of the study can become an input to stakeholders related to the development of small-scale cocoa industry in West Sumatera.

Monilia (Moniliophtora roreri) and the Post‐Development of Belizean Cacao

AbstractThis article explores how agro‐technical development works to change Mopan Maya relations with the natural world through a case study of the emergent fungus Monilia in the Belizean cacao industry. I show how technical development projects generate the environmental conditions that allow detrimental diseases like Monilia to become widespread, while subsequent efforts to mitigate the resultant epidemic serve as powerful vehicles for the further perpetuation of Western scientific agriculture. I argue that these interventions transform indigenous environmental paradigms from relational to mononatural, organized around human mastery over a singular, objective environment.

Development Model of Cacao Agro-Industry with Sectoral Competitive Advantage Based in Southeast Sulawesi, Indonesia

The aim of this research was to explore the development model of cacao industry with sectoral competitive advantage. More specifically, the purposes of this research were to examine and explain the effects of market orientation, supply chain flexibility and strategic location toward competitive advantage in cacao agro-industry. Design used in this research was explanatory research with process of data collection through survey method by using questionnaire. Unit analysis of this research was leaders/managers of cacao industry. Data analysis method used is the generalized structured component analysis. Findings of this research show that market orientation and strategic location have positive effect and significant toward competitive advantage. But, supply chain flexibility has no significant effect towards competitive advantage. Furthermore, control variable of institutional economic has positive and significant effect towards competitive advantage. Practical implication can give understanding and information for managers of cacao industry in implementing their market orientation, supply chain flexibility and market strategy by assessing the ability of partner supply chain to respond market changes in obtaining and maintaining the competitive advantage. Limitation of this study is that in delivering the analysis, analysis relation of cross sectional was limited to respondents, manager/leaders only. Further researches need to involve cacao farmers, customers, government and business partners in the sampling. Besides that, commodity which was focused was very specific that is cacao industry. Therefore, put in concern about factors of season and farmers involvement need to get serious attention. Originality of this research can prove and explain integration of conceptual model in structural relation among market orientation, strategic location, and supply chain flexibility in improving competitive advantage. Furthermore, this research also gives empirical evidence of the role of variable control of institutional economic has significant effect towards competitive advantage.

Actividad antibacteriana de la cáscara de cacao, Theobroma cacao L

RESUMENObjetivo. Evaluar la actividad antibacteriana de diferentes fracciones de la cáscara de cacao (Theobroma cacao L.). Materiales y métodos. Se evaluó la actividad antibacteriana mediante el método de difusión en agar de diferentes fracciones de la cáscara de cacao, empleando cepas autóctonas y de referencia ATCC. Posteriormente, se hizo un análisis de estas fracciones por cromatografía líquida de alta eficiencia y cromatografía de gases acoplada a espectrometría de masas. Resultados. La fracción clorofórmica presentó actividad antibacteriana frente a Bacillus cereus ATCC 11778 y Streptococcus agalactiae (autóctona), con porcentajes de inhibición de 34.90% (100 μg/μl) y 52.40% (100 μg/μl) respectivamente. También se evidenció una concentración mínima inhibitoria de 512 μg/ml frente a Bacillus cereus ATCC 11778 y de 128 μg/ml frente a Streptococcus agalactiae. Conclusiones. Este trabajo es el primer reporte a saber en Colombia sobre actividad antibacteriana in vitro de la cáscara de cacao, el cual resulta ser un avance importante para esta agroindustria. Esta investigación abre paso a otros estudios relacionados para establecer el espectro de inhibición frente a otros microorganismos.

Synthesis and characterization of sodium carboxymethylcellulose from pod husk of Cacao (Theobroma cacao L.)

Cacao pod husk (Theobroma cacao L.) is a by product of the cacao industry, rich in cellulose. The methodology to synthesize and uniqueness of the sodium carboxymethylcellulose (Na-CMC) is suggested by cellulose extraction from pod husk of cacao. Na-CMC was synthesized by using 20 ml NaOH at five various concentrations (11.59, 15, 20, 25, and 28.41% w/v) at 25°C for 1 h; followed with 5 sodium monochloracetate (NMCA) samples 3.18, 4, 5, 6 and 6.68 g, respectively with 5 g of cellulose was added to slurry at various temperature (46.59, 50, 55, 60 and 63.41°C) for 3 h. The response surface methodology used to determine the optimum condition for synthesis of NaCMC. The data showed that the optimum condition is 15% NaOH with 4 g NMCA, at 55.93°C for 3 h. Extracted Na-CMC has 0.75° of substitution (DS), 3.73 g/g water holding capacity (WHC), 2.12 g/g oil holding capacity (OHC), 56.61 lightness, 206.10 cps viscosity, and 141.60% yield. Key words: Cellulose, carboxymethylcellulose, cacao pod husk.

Limbah Cair Industri Kakao Sebagai Bahan Pembuat Nata

This research was aimed to utilize the liquid waste of cacao industry as raw material for nata production. Research was performed in two steps : the first steps was clarification process using active charcoal in different waste dilllutions and the second step was the production of nata. Result of first step showed that active charcoal concentration and dilution treatment showed their effect of all parameters studied. The best result was obtained by treatment of 5% active charcoal concentration and the dilllution of cacao waste : water in 1:3 ratio. The production of nata in the second step of research was performed using this optimal clarification condition. Data showed that the combination treatment of 4% sucrose concentration and 0,4% of (NH4)2SO4 was elected as the best process that gave the best quality of nata. The best treatment showed product characteristic : 83,87% of fermentation yield; 95,23% of moisture content; 4,22% of fiber content; brightness (L*) of 42,87; 0,01 mm/g.dt of textur and 2,42 cm of nata thickness.

Control of Chinese rose beetle through the use of solar-powered nighttime illumination

Chinese rose beetle, Adoretus sinicus (Burmeister) (Coleoptera: Scarabaeidae: Adoretini), found in Asia and the Pacific Islands, was first reported in Hawaii (USA) in 1891. Adults feed at night on leaves of a wide range of plant species. Aggregate feeding can stunt or even kill host plants. Chinese rose beetle is one of the most serious pests of young cacao [Theobroma cacao L. (Malvaceae)] trees, and has been a problem for orchard establishment in the developing cacao industry in Hawaii. One promising pesticide-free control method takes advantage of the avoidance of light by adult beetles when they select the plant on which they will feed at night. We tested the effectiveness of nighttime illumination provided by a portable solar-based light-emitting diode spotlight system as a means of reducing beetle populations on host plants, first using castor bean, Ricinus communis L. (Euphorbiaceae), as a test plant, followed by orchard-scale testing in young cacao orchards. Using Chinese rose beetle-populated castor bean plants, counts were made of numbers of beetles on both non-illuminated and illuminated plants. Nighttime illumination suppressed beetle numbers, with increased suppression associated with extended duration of illumination (number of nights) and with increased intensity of illumination: 2.5 lux was sufficient to give >50% suppression, and 4.0 lux was sufficient to give >75% suppression over 4 nights of illumination. In cacao orchard tests, there was over 93% reduction of beetle numbers in each test orchard, following 4 nights of illumination. The results clearly show that nighttime illumination can be used as a means of reducing Chinese rose beetle population size, and presumed aggregate defoliation on a host plant. We believe that this is the first report of the use of nighttime illumination as a means of suppressing damage of plants by insects.

Witches’ brooms and frosty pods: Two major pathogens of cacao

The agaric Crinipellis perniciosa (Tricholomataceae) is a hemibiotrophic pathogen which causes witches’ broom disease of cacao and has recently decimated the Brazilian cacao industry. In addition to the pathogenic cacao (C‐) biotype, other biotypes are found in association with unrelated plant taxa, notably bignoniaceous lianas (L‐biotype), solanaceous hosts (S ‐biotype), and the shrub Heteropterys acutifolia (H‐biotype). The C‐and S‐biotypes are non‐outcrossing and form broom symptoms on hosts, whereas the L‐biotype is outcrossing and asymptomatic. Phylogenetic analysis of several regions of the rRNA locus revealed near identity between C‐ and S‐biotype isolates from diverse locations, with the L‐ and H‐biotypes forming separate groupings. Preliminary analysis of sequence data from Moniliophthora roreri, causal agent of frosty pod disease, indicates that this morphologically distinct pathogen may be closely related to C. perniciosa. Similarities in host infection between C. perniciosa and M. roreri have previously been noted but it is difficult to reconcile the gross morphological differences. Pairings between C. perniciosa and M. roreri gave rise to a clamped dikaryotic mycelium suggestive of a hybridisation event.

DIVERSIFICATION OF TREE CROPS: DOMESTICATION OF COMPANION CROPS FOR POVERTY REDUCTION AND ENVIRONMENTAL SERVICES

New initiatives in agroforestry are seeking to integrate indigenous trees, whose products have traditionally been gathered from natural forests, into tropical farming systems such as cacao farms. This is being done to provide from farms, marketable timber and non-timber forest products that will enhance rural livelihoods by generating cash for resource-poor rural and peri-urban households. There are many potential candidate species for domestication that have commercial potential in local, regional or even international markets. Little or no formal research has been carried out on many of these hitherto wild species to assess potential for genetic improvement, reproductive biology or suitability for cultivation. With the participation of subsistence farmers a number of projects to bring candidate species into cultivation are in progress, however. This paper describes some tree domestication activities being carried out in southern Cameroon, especially with Irvingia gabonensis (bush mango; dika nut) and Dacryodes edulis (African plum; safoutier). As part of this, fruits and kernels from 300 D. edulis and 150 I. gabonensis trees in six villages of Cameroon and Nigeria have been quantitatively characterized for 11 traits to determine combinations defining multi-trait ideotypes for a genetic selection programme. I. gabonensis fruits are rich in vitamin A (67 mg 100 ml−1), while the kernels are rich in fat (51.3%) and contain a polysaccharide that is a food thickener. The fruits of D. edulis are also rich in oil (31.9%) and protein (25.9%). This poverty-reducing agroforestry strategy is at the same time linked to one in which perennial, biologically diverse and complex mature-stage agroecosystems are developed as sustainable alternatives to slash-and-burn agriculture. To meet the objective of poverty reduction, however, it is crucial that market expansion and creation are possible. Hence, for example, it is important to determine which marketable traits are amenable to genetic improvement. While some traits (such as fruit and kernel mass) that benefit the farmer are relatively easy to identify, there are undoubtedly others that are important to the food, pharmaceutical or other industries which require more sophisticated chemical evaluation. There is a need, therefore, for better linkages between agroforesters and the private sector. The domestication activities described are relevant to the enrichment of smallholder cacao farms and agroforests. This diversification is seen as being important for the support of the cacao industry.

South Pacific Commission

From April 28 to May 7, 1952 the ninth session of the South Pacific Commission was held in Noumea, New Caledonia.1 The session, which was primarily concerned with administrative matters, was under the chairmanship of N. A. J. de Voogd (Netherlands). As a result of agreement by member governments at the eighth session to include Guam and the Trust Territory of the Pacific Islands within the scope of the Commission, at the ninth session it was agreed unanimously to extend Commission activities to embrace these territories. Assurances of cooperation in Commission activities were given on behalf of both territories by the Acting Senior Commissioner for the United States (Leebrick) and the Secretary of Guam (Herman). Special aspects of its work program were reviewed by the Commission. The printing of two project reports dealing with the area was authorized: one, on economic development of coral atolls covered a survey made for the Commission in 1951 in the Gilbert Islands and the other was concerned with the possibilities of expanding the cacao industry in the area.

Entomological Aspects of ‘Swollen Shoot' of Cacao

THE rapid spread of the deadly ‘swollen shoot' disease of cacao first recorded by Steven1 in 1936 justly gives cause for alarm. Now believed to be due to a virus transmitted by three species of insects of the family Pseudococcidae, this malady of unknown origin bids fair to destroy the West African cacao industry. That this is realized by the people of West Africa is evident from the lively public interest in the problem.

Coccids attacking Cacao (Theobroma cacao, L.), in West Africa, with Descriptions of five new Species

Cacao was introduced into West Africa in the latter years of the last century and for a time remained relatively free from pests and diseases. It is, in fact, only recently that two major scourges have developed to a point where they are threatening the future of the cacao industry in the Gold Coast and Nigeria. The first, the cacao Mirids (Sahlbergella singularis, Hagl., andDistantiella theobroma, Dist.) is outside the range of the present paper. The second, and most important, is a virus disease, known as “Swollen Shoot”, which is transmitted from tree to tree by at least three species of mealybugs of the family Pseudococcidae.

A Morphological Change Induced in Leaves of Theobroma cacao by Mineral Deficiency

PREPARATIONS for breeding a strain of Theobroma cacao L. resistant to the swollen-shoot virus which threatens the cacao industry of the Gold Coast1 have included the collection of commercial types of T. cacao and of related species of Theobroma, some of which have been shown to give compatible crosses with T. cacao2. With the assistance of the Imperial College of Tropical Agriculture, seed from selected trees has been introduced to the Gold Coast from Trinidad. As a precaution against the introduction of witches' broom disease (Marasmius perniciosus Stahel) pods were surface-sterilized before dispatch by air; seedlings were quarantined for a minimum period of six months in Accra, which is twenty miles distant from the cacao-growing area.

Bromeliad Malaria in Trinidad, British West Indies 1

Summary Lutz (1903) first considered the possibility that anopheline mosquitoes of the subgenus Kerteszia might be involved in malaria transmission. He concluded, on epidemiological grounds, that Anopheles lutzi Theobald (= cruzi D. & K.) was a vector in Sao Paulo. However, Knab, stressing the connection between the feeding habits of insects and their importance as vectors of disease strongly opposed Lutz's view, maintaining that since Anopheles lutzi was a forest mosquito it would not have sufficient contact with man to transmit malaria. Independently, Urich and later de Verteuil believed that Anopheles (Kerteszia) bellator D. & K. was involved in the malaria complex in Trinidad, and this was confirmed eventually by Rozeboom and Laird, and also by Downs, Gillette, and Shannon. It is shown that in spite of the fact that Anopheles bellator is a forest mosquito it is intimately associated with man in the cacao areas of Trinidad. Two principal factors are adduced to account for this contact: in the first place Anopheles bellator inhabits the drier microclimates of the forest and is therefore able to leave forest as such for the drier conditions offered by cacao estates and the open spaces in the villages; secondly, the cacao industry has brought relatively large human settlements into immediate contact with the forests of cacao and immortelle trees, which support both larval and adult populations of A. bellator and heavy growths of water-holding bromeliads in which the anophelines breed. The breeding of A. bellator is restricted to certain bromeliad species. Its absence in some very common species such as Aechmea nudicaulis is a fact of practical importance. Again, bellator does not occur all over the island where forests and cacao estates exist. It is restricted to areas of high rainfall. In discussing control problems the writers do not consider that the simple removal of plants by hand could ever be adopted as a regular control procedure. It is too slow, expensive, and dangerous. It is shown that copper sulphate may be used as a selective herbicidal spray to destroy the bromeliad infestations without damaging the commercially important cacao trees or the immortelles. In field practice the heavy spraying equipment developed by the United States Department of Agriculture for the control of the gypsy moth is found to be highly satisfactory. This control method is much faster, cheaper, and safer than removal of bromeliads by hand. Finally it is pointed out that a change in agricultural practice, namely, the abandonment of interplanted immortelle shade trees and the adoption of windbreaks, would remove the ecological basis of the disease, which is the microclimatic condition produced by immortelle trees in existing cacao estates. Following such a change, which is now being encouraged by the Government of Trinidad and Tobago, endemic bromeliad malaria could be expected to disappear from the center of the island.

Cacao in Costa Rica

C O^OSTA RICA was of little importance as a cacao producing country until the United Fruit Company became interested in the industry in 1914. Desirous of replacing financial losses sustained by the decline of the banana industry in this country, the company replanted parts of the abandoned banana lands to cacao. This was an impetus to the industry and a rapid extension took place. Costa Rica has become the sixth most important cacao producing country of Latin America and the thirteenth of the world. It produced 8,074 tons in 1937. This comparatively new region produces the ordinary cacao of high quality, second only to that produced by Bahia, the premier producer of ordinary cacao of the world. The cacao industry of Costa Rica is of secondary importance to the country. Here on the Caribbean lowlands cultivation of bananas is the primary industry. Both industries are dominated largely by foreign capital. The coffee industry which is carried on chiefly on the highlands is the mainstay of Costa Ricans. The banana and cacao industries have less to do with the real lives of the natives except to contribute the returns usually received from industries that are exploited by foreign capital (Figure 1). Practically all the cacao of Costa Rica is produced in the low-lying district of the Caribbean coastal plain, although there is a small amount produced on the Pacific slopes in the hinterland of Punta Arenas. Because of insufficient rainfall in this latter area, the crop here is raised under irrigation. A few thousand pounds are exported every year, but due to the competition of the district on the Caribbean coast and other producing regions outside the country, production of this district figures little in the export trade. On the Caribbean lowland cacao is planted on available valley land or nearby hillsides in selected spots west from Limon along the Northern Railway to the Reventazon river and also on what is called the Old Line that branches off from the main railway at La Junta. In addition to these spots there are areas devoted to cacao southeast from Limon located two or three miles inland from the coast, extending to the Panama border, particularly along the Banano and Estrella rivers (Figures 2 and 3). Published statistics of cacao acreage are admittedly deficient. Those given in the government's annual publication for 1928 are 63,113 acres, having over 22,000,000 trees. There was little or no extension the next two years. In 1931 and since, low prices have made the industry unprofitable in many cases leading to the abandonment of acreage and destruction of trees to make room for other crops. The lowlands of Central America bordering the Caribbean Sea have a rainy low-latitude type of climate. They have high uniform temperatures, high relative humidity at all times and heavy rainfall well distributed throughout most of the year. The highest temperature at sea level reaches 95 degrees F. and for moderate elevation inland 90 degrees F. Extreme minimum temperatures range from 60

Cacao Industry of Brazil

RAZIL exceeds all other Latin American countries by far in the exportation of cacao. The exportation of' 134,172 tons in 1936 was the largest to date, in the history of the country and was exceeded in world export only by the Gold Coast of Africa which exported in the same year 338,386 tons. (Since relatively small amounts of cacao are consumed in Brazil and the Gold Coast, export figures and production figures are practically the same.) Cacao grows wild in several regions of Brazil where natural conditions are favorable. Its commercial production is generally confined to the states of Amazonas of the Upper Amazon Basin, in Para' and Piaui' of the Lower Amazon Basin and to several selected areas on the coastal lowlands of eastern Bahia.