ICGD 2003: International Cocoa Germplasm Database Version 5.2. CD-ROM

The current version of this database on CD-ROM contains information on 14 127 cocoa (Theobroma cacao) clones and their 14 112 synonyms, the origin and history of the clones and the clone names, and accession lists for 48 of the major cocoa gene banks including quarantine stations. Also included are morphological data for leaves, fruits and seeds, disease reactions, quality and agronomic characters, and reference information on common abbreviations and acronyms, cocoa gene bank addresses and a full bibliography (with hyperlinked reference to data). New additions are 748 photographs and drawings of 428 individual clones in 11 different locations. Also included are 376 profiles for 15 simple sequence repeat primer pairs on 331 clones held in the University of Reading Intermediate Cocoa Quarantine Facility. Minimum system requirements are Windows 95 or later, a Pentium 166 with 32 MB RAM, CD-ROM drive and a minimum 20 MB hard disk space. A user guide is included in the package.

Investigation on Cacao swollen shoot virus (CSSV) pollen transmission through cross-pollination

DNA- and RNA-based polymerase chain reaction (PCR) systems were used with Cacao swollen shoot virus (CSSV) primers designed from conserved regions of the six published genomic sequences of CSSV to investigate whether the virus is transmissible from infected trees through cross-pollination to seeds and seedlings. Pollen was harvested from CSSV infected cocoa trees and used to cross-pollinate flowers of healthy cocoa trees (recipient parents) to generate enough cocoa seeds for the PCR screening. Adequate precautions were taken to avoid cross-contamination during duplicated DNA extractions and only PCR results accompanied by effective positive and negative controls were scored. Results from the PCR analyses showed that samples of cocoa pod husk, mesocarp and seed tissues (testa, cotyledon and embryo) from the cross-pollinations were PCR negative for CSSV DNA. Sequential DNA samples from new leaves of seedlings resulting from the cross-pollinated trees were consistently PCR negative for presence of portions of CSSV DNA for over 36 months after germination. A reverse transcription-PCR analysis performed on the seedlings showed negative results, indicating absence of functional CSSV RNA transcripts in the seedlings. None of the seedlings exhibited symptoms characteristic of the CSSV disease, and all infectivity tests on the seedlings were also negative. Following these results, the study concluded that although CSSV DNA was detected in pollen from CSSV infected trees, there was no evidence of pollen transmission of the virus through cross-pollination from infected cocoa parents to healthy cocoa trees. Keywords:badnavirus;CSSV;PCR;pollen;seed transmission;Theobroma cacao

Optimal planning of cocoa clonal selection programmes

Data from three cocoa (Theobroma cacao) clonal selection trials are used to investigate the genetic and environmental components of variation in yield and the percentage of total pods affected by black pod disease (Phytophtora pod rot). Simulations based on these estimated components of variation are then used to discuss the best choice in future of numbers of clones, replicates and years of harvest to maximise selection advances in the traits measured. The three main conclusions are the need to increase the number of clones at the expense of the number of replicates of each clone, the diminishing returns from additional years of harvesting and the importance of widening the genetic base of the clones chosen to be tested.

High-resolution melt and morphological analyses of mealybugs (Hemiptera: Pseudococcidae) from cacao: tools for the control of Cacao Swollen Shoot Virus spread

BACKGROUND: Mealybugs (Hemiptera: Coccoidea: Pseudococcidae) are key vectors of badnaviruses, including Cacao Swollen Shoot Virus (CSSV) the most damaging virus affecting cacao (Theobroma cacao L.). The effectiveness of mealybugs as virus vectors is species dependent and it is therefore vital that CSSV resistance breeding programmes in cacao incorporate accurate mealybug identification. In this work the efficacy of a CO1-based DNA barcoding approach to species identification was evaluated by screening a range of mealybugs collected from cacao in seven countries. RESULTS: Morphologically similar adult females were characterised by scanning electron microscopy and then, following DNA extraction, were screened with CO1 barcoding markers. A high degree of CO1 sequence homology was observed for all 11 individual haplotypes including those accessions from distinct geographical regions. This has allowed for the design of a High Resolution Melt (HRM) assay capable of rapid identification of the commonly encountered mealybug pests of cacao. CONCLUSIONS: HRM Analysis (HRMA) readily differentiated between mealybug pests of cacao that can not necessarily be identified by conventional morphological analysis. This new approach, therefore, has potential to facilitate breeding for resistance to CSSV and other mealybug transmitted diseases.

Pre-Columbian ring ditch construction and land use on a “chocolate forest island” in the Bolivian Amazon

We present a palaeoecological investigation of pre-Columbian land use in the savannah “forest island” landscape of north-east Bolivian Amazonia. A 5700 year sediment core from La Luna Lake, located adjacent to the La Luna forest island site, was analysed for fossil pollen and charcoal. We aimed to determine the palaeoenvironmental context of pre-Columbian occupation on the site and assess the environmental impact of land use in the forest island region. Evidence for anthropogenic burning and Zea mays L. cultivation began ~2000 cal a BP, at a time when the island was covered by savannah, under drier-than-present climatic conditions. After ~1240 cal a BP burning declined and afforestation occurred. We show that construction of the ring ditch, which encircles the island, did not involve substantial deforestation. Previous estimates of pre-Columbian population size in this region, based upon labour required for forest clearance, should therefore be reconsidered. Despite the high density of economically useful plants, such as Theobroma cacao, in the modern forest, no direct pollen evidence for agroforestry was found. However, human occupation is shown to pre-date and span forest expansion on this site, suggesting that here, and in the wider forest island region, there is no truly pre-anthropogenic ‘pristine’ forest.

Optimising mirid control on cocoa farms through complementary monitoring systems

Mirids (Sahlbergella singularis and Distantiella theobroma) are the most important insect pests affecting cocoa production across West Africa. Understanding the population dynamics of mirids is key to their management, however, the current recommended hand-height assessment method is labour intensive. The objective of the study was to compare recently developed mirid sex pheromone trapping and visual hand-height assessment methods as monitoring tools on cocoa farms and to consider implications for a decision support system. Ten farms from the Eastern and Ashanti regions of Ghana were used for the study. Mirid numbers and damage were assessed fortnightly on twenty trees per farm, using both methods, from January 2012 to April 2013. The mirid population increased rapidly in June, reached a peak in September and began to decline in October. There was a significant linear relationship between numbers of mirids sampled to hand-height and mirid damage. High numbers of male mirids were recorded in pheromone traps between January and April 2012 after which there was a gradual decline. There was a significant inverse relationship between numbers of trapped adult mirids and mirids sampled to hand-height (predominantly nymphs). Higher temperatures and lower relative humidities in the first half of the year were associated with fewer mirids at hand-height but larger numbers of adult males were caught in pheromone traps. The study showed that relying solely on one method is not sufficient to provide accurate information on mirid population dynamics and a combination of the two methods is necessary.

Landscape and farm scale management to enhance biodiversity conservation in the cocoa producing region of southern Bahia, Brazil

In southern Bahia, Brazil, large land areas are used for the production of cocoa (Theobroma cacao), which is predominantly grown under the shade of native trees in an agroforestry system locally known as cabruca. As a dominant forest-like landscape element of the cocoa region, the cabrucas play an important role in the conservation of the region`s biodiversity. The purpose of this review is to provide the scientific basis for an action plan to reconcile cocoa production and biodiversity conservation in southern Bahia. The available research collectively highlights the diversity of responses of different species and biological groups to both the habitat quality of the cabrucas themselves and to the general characteristics of the landscape, such as the relative extent and spatial configuration of different vegetation types within the landscape mosaic. We identify factors that influence directly or indirectly the occurrence of native species in the cabrucas and the wider landscape of the cocoa region and develop recommendations for their conservation management. We show that the current scientific knowledge already provides a good basis for a biodiversity friendly management of the cocoa region of southern Bahia, although more work is needed to refine some management recommendations, especially on shade canopy composition and density, and verify their economic viability. The implementation of our recommendations should be accompanied by appropriate biological and socioeconomic monitoring and the findings should inform a broad program of adaptive management of the cabrucas and the wider cocoa landscape.

Conservation in tropical landscape mosaics: the case of the cacao landscape of southern Bahia, Brazil

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.

Viabilidade econômica do cultivo de cacaueiro e bananeira irrigados no Maranhão

Este trabalho teve por objetivo estudar a viabilidade econômica da produção consorciada de cacau e banana na região do Perímetro Irrigado Tabuleiro de São Bernardo nos municípios de Magalhães de Almeida e Araioses, estado do Maranhão (MA), tendo em vista a ampla disponibilidade de recursos naturais para o cultivo e a potencialidade de ser uma região de escape das principais doenças que afetam as culturas de cacau e banana. O trabalho verifica a oportunidade de negócio de produção de cacau e banana na região do rio Parnaíba. O estudo utiliza projeções de fluxo de caixa e os desconta para o Valor Presente Líquido (VPL) para aferir a viabilidade econômica do negócio de produção de cacaueiro e bananeira nesta região do Brasil. Foram realizadas pesquisas bibliográficas para analisar as características edafoclimáticas da microrregião, as características fisiológicas do cacaueiro e seu consórcio com a bananeira para o sombreamento temporário necessário durante a fase de crescimento do cacaueiro. Foi sugerido o pacote de alta tecnologia para a produção de cacaueiro, dada a necessidade de irrigação para o seu cultivo. Diferentes produtividades e preços de cacau e banana foram utilizados para analisar a sensibilidade económica deste negócio. Ao projetar um fluxo de caixa, foi possível fazer uma análise sobre o negócio, viabilidade e riscos. Deve-se notar que não há grandes áreas produtoras de cacau na região do rio Parnaíba. Porém, há pequenas áreas de cacau em regiões semiáridas (ou de cerrado). Assim, a produção vegetal carece de comprovação de produção em larga escala para atestar de modo prático algumas das premissas econômico-financeiras adotadas para analisar a viabilidade da produção de cacau e banana no Perímetro Irrigado Tabuleiro de São Bernardo.

Indução de calos embriogênicos em explantes de cupuaçuzeiro

Objetivou-se a indução de calos embriogênicos em cupuaçuzeiro, em função do tipo de explante e meio de cultura. Foram testados como explantes, segmentos cotiledonares e eixos embrionários divididos em três partes: região da plúmula, radícula e hipocótilo. Os explantes foram cultivados em 2 diferentes meios de cultura: 1) MS suplementado com 2,4-D (1 mg L-1) e Cinetina (0,25 mg L-1); 2) MS acrescido de ANA (5 mg L-1) e Cinetina (0,25 mg L-1). Constatou-se que a região do hipocótilo foi a parte mais responsiva do eixo embrionário, formando calos com aspecto branco e friável. As auxinas testadas nos meios não estimularam o processo embriogênico em calos de cupuaçuzeiro.

Cigarras (Hemiptera: Cicadidae: Tibicinidae) associadas ao cafeeiro: distribuição, hospedeiros e chave para as espécies

É apresentada a distribuição de 10 espécies de cigarras associadas ao cafeeiro, Coffea arabica, nos Estados de Minas Gerais, São Paulo e Paraná, Brasil. A informação sobre a distribuição geográfica destas espécies no Continente Americano, afora o Brasil, foi baseada na literatura. Para o Brasil, as localidades de ocorrência de cigarras foram baseadas na literatura, nos levantamentos realizados e em exemplares de coleções nacionais. Outros sete hospedeiros, além do cafeeiro, foram também registrados: esponjeira (Acacia farnesiana), sibipiruna (Caesalpinia peltophoroides), Cassia spp., amoreira (Morus alba), abacateiro (Persea americana), angico (Piptadenia sp.) e cacaueiro (Theobroma cacao). São apresentadas chaves de identificação, baseadas nas características gerais e na genitália masculina.

Estudos biológicos de cochonilhas do gênero Planococcus (Hemiptera: Pseudococcidae) em diferentes hospedeiros

This work was carried out to study the development of populations of the genus Planococcus in different plant species, aiming at the verification of host specificity. The mealybugs Planococcus minor were obtained from cocoa plants (Theobroma cacao L.) and coffee crop (Coffea canephora L.), and Planococcus citri from citrus seedlings (Citrus sinensis L. Osbeck). Single eggs were transferred to Petri dishes containing leaf discs of cocoa (T. cacao cultivar Catongo), coffee (Coffea arabica L. cultivar Mundo Novo) and citrus (C. sinensis cultivar Pera Rio). They were maintained on a water-agar slide at 1%, with the abaxial surface turned upwards. The dishes were sealed with a PVC plastic film and kept in climatized chambers regulated at 25 [plus or minus] 1[degrees] C, 70 [plus or minus] 10% RH and 12 hours of photophase. For the mealybugs coming from cocoa plants, the citrus substrate prolonged the nymphal development of the males (26.0 days). In the nymphal period of females and males coming from coffee plants, the coffee substrate allowed a shorter duration of that period (19.2 and 21.3 days, respectively) and, in addition to having providing a longer longevity to the females (59.1 days). The highest rates of mortality were obtained when they were reared on the cocoa substrate, regardless of the host plant from which they were originally collected, and when kept on citrus, for insects collected on coffee plants. P. citri and P. minor have higher preference for coffee substrate regardless of the original host, thus showing partial host specificity.

MYCELIAL DEVELOPMENT of Lentinula edodes IN CULTURE MEDIA WITH DIFFERENT ORGANIC SUBSTRATES

The radial mycelial growth of Lentinula edodes (Berk) Pegler, strain LE-96/13, was studied in culture media prepared with organic residues extract, by using substrates prepared with pineapple (Ananas comosus (L.) Merril) crown, Astrocaryum aculeatum Meyer peel, Theobroma grandiflorum Schum shell, Musa sp. (genomic group AAB, subgroup Pacovan) peel, and Musa sp. (genomic group AAB, subgroup Praia) peel, with three supplementation levels with wheat bran (0, 10 and 20%), and incubated at 25 degrees C. The experimental design was totally randomized, in a 5x3 factorial scheme, adding up 15 treatments with 4 repetitions, and each repetition corresponding to a Petri dish. The diameter of the colony was evaluated daily during nine days of incubation. After that period, it was verified that the highest mycelial growth averages of strain LE-96/13 of L. edodes were found in culture media prepared with T. grandiflorum Schum shell (whose supplementation with wheat bran was favorable for Mushroom development) and A. aculeatum Meyer peel (whose supplementation did not favor the mycelial growth of L. edodes in relation to the medium not supplemented).

Características químicas de substratos utilizados na produção de mudas de cacaueiros

O objetivo deste trabalho foi realizar monitoramento químico de seis substratos utilizados na produção de mudas de cacaueiros. Os substratos receberam 10 volumes (100mL, cada) de água destilada, e no lixiviado coletado foram determinados o pH, a condutividade elétrica (CE) e os teores de sódio (Na) e potássio (K) em solução. Os valores de pH variaram de 5,0 a 8,0 em Plantmax® e composto do tegumento da amêndoa do cacau (CTAC), respectivamente. Verificou-se que, a partir do primeiro volume lixiviado, a CE de todos os substratos foi reduzida. Foram encontradas correlações positivas para a CE em relação ao K e Na da fibra de coco (FC) (r=0,83 e 0,72 P<0,05) e CTAC (r=0,98 e 0,99 P<0,05). Os resultados indicam que a FC e o CTAC deveriam ser usados após pré-lavagens. Verificou-se que, embora a FC apresente na primeira lixiviação valor de CE superior aos demais substratos, o valor ideal da 2,0 dSm-1 é alcançado na segunda lixiviação. Os teores de K e Na são um indicativo do valor da CE em FC e CTAC.

Efeito do ácido indolbutírico e época de coleta no enraizamento de estacas semi-lenhosas do cacaueiro

O objetivo do trabalho foi verificar o efeito do ácido indolbutírico (AIB) no enraizamento de estacas do cacaueiro. O delineamento experimental foi o inteiramente casualizado, em esquema fatorial 3 x 5 x 2, envolvendo 3 clones (Cepec 2008, CCN 51 e TSH 1188), 5 concentrações de ácido indolbutírico AIB (0; 1.000; 3.000; 6.000 e 9.000 mg kg-1), duas épocas do ano (verão e inverno),, cinco repetições e 10 estacas por parcela. A avaliação do experimento foi realizada 120 dias após o plantio e analisadas as seguintes variáveis: percentagem de sobrevivência (SOB), número de brotações (NB), matéria seca das brotações (MSB), percentagem de estacas enraizadas (ENR), número de raízes (NR) e matéria seca de raízes (MSR). Os fatores época do ano e concentração de AIB apresentaram efeito significativo para as variáveis estudadas quando isolados e em interação com os clones. Os dados obtidos possibilitaram concluir que o valor médio da concentração ideal de AIB (CI) foi de 4.169 mg kg-1 e 3.985 mg kg-1 no verão e inverno, respectivamente. Verificou-se que os clones apresentam diferentes respostas em relação à CI de AIB e época do ano. de modo geral, as CIs no verão foram maiores que no inverno. Os resultados mostraram que a época de plantio e a concentração de AIB influenciaram de maneira mais expressiva na sobrevivência e enraizamento das estacas dos clones Cepec 2008 e CCN 51 e em menor intensidade no clone TSH 1188. Existe uma concentração ideal de AIB para cada um dos clones estudados.