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.

Photosynthetic activity and early growth of four Cacao genotypes as influenced by different shade regimes under West African dry and wet season conditions

The physiological performance of four cacao clones was examined under three artificial shade regimes over the course of a year in Ghana. Plants under light shade had significantly higher photosynthetic rates in the rainy seasons whereas in the dry season there was a trend of higher photosynthetic rates under heavy shade. The results imply that during the wet seasons light was the main limiting factor to photosynthesis whereas in the dry season vapour pressure deficit was the major factor limiting photosynthesis through stomatal regulation. Leaf area was generally lower under heavier shade but the difference between shade treatments varied between clones. Such differences in leaf area allocation appeared to underlie genotypic differences in final biomass production in response to shade. The results suggest that shade for young cacao should be provided based on the current ambient environment and genotype.

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.

The influence of shade and organic fertilizer treatments on the physiology and establishment of Theobroma cacao clones

Aims: This experiment aimed to determine whether the soil application of organic fertilizers can help the establishment of cacao and whether shade alters its response to fertilizers. Study Design: The 1.6 ha experiment was conducted over a period of one crop year (between April 2007 and March 2008) at the Cocoa Research Institute of Ghana. It involved four cacao genotypes (T 79/501, PA 150, P 30 [POS] and SCA 6), three shade levels (‘light’, ‘medium’ and ‘heavy’) and two fertilizer treatments (‘no fertilizer’, and ‘140 kg/ha of cacao pod husk ash (CPHA) plus poultry manure at 1,800 kg/ha). The experiment was designed as a split-plot with the cacao genotypes as the main plot factor and shade x fertilizer combinations as the sub-plots. Methodology: Gliricidia sepium and plantains (Musa sapientum) were planted in different arrangements to create the three temporary shade regimes for the cacao. Data were collected on temperature and relative humidity of the shade environments, initial soil nutrients, soil moisture, leaf N, P and K+ contents, survival, photo synthesis and growth of test plants. Results: The genotypes P 30 [POS] and SCA 6 showed lower stomatal conductance under non-limiting conditions. In the rainy seasons, plants under light shade had the highest CO2 assimilation rates. However, in the dry season, plants under increased shade recorded greater photosynthetic rates (P = .03). A significant shade x fertilizer interaction (P = .001) on photosynthesis in the dry season showed that heavier shade increases the benefits that young cacao gets from fertilizer application in that season. Conversely, shade should be reduced during the wet seasons to minimize light limitation to assimilation. Conclusion: Under ideal weather conditions young cacao exhibits genetic variability on stomatal conductance. Also, to optimize plant response to fertilizer application shade must be adjusted taking the prevailing weather condition into account.

Cacao swollen shoot virus in Nigeria: analysis of a pathogen and its vectors

Cacao swollen shoot virus (CSSV) causes the Cacao swollen shoot virus disease (CSSVD) and significantly reduces production in West African cacao. This study characterised the current status of the disease in the major cacao growing States in Nigeria and attempted a clarification on the manner of CSSV transmission. Two separate field surveys and sample collections were conducted in Nigeria in summer 2012 and spring 2013. PCR-based screening of cacao leaf samples and subsequent DNA sequencing showed that the disease continues to persist in Ondo and Oyo States and in new cacao sites in Abia, Akwa Ibom, Cross River and Edo States. Mealybug samples collected were identified using a robust approach involving environmental scanning electron microscopy, histology and DNA barcoding, which highlighted the importance of integrative taxonomy in the study. The results show that the genus Planococcus (Planococcus citri (Risso) and/or Planococcus minor (Maskell)) was the most abundant vector (73.5%) at the sites examined followed by Formicococcus njalensis (Laing) (19.0 %). In a laboratory study, the feeding behaviour of Pl. citri, Pseudococcus longispinus (Targioni-Tozzetti) and Pseudococcus viburni (Signoret) on cacao were investigated using electrical penetration graph (EPG) analysis. EPG waveforms reflecting intercellular stylet penetration (C), extracellular salivation (E1e), salivation in sieve elements (E1), phloem ingestion (E2), derailed stylet mechanics (F), xylem ingestion (G) and non-probing phase (Np) were analysed. Individual mealybugs exhibited marked variation within species and significantly differed (p ≤ .05) between species for E1e and E1. PCR-based assessments of the retention time for CSSV in viruliferous Pl. citri, Ps. longispinus and Ps. viburni fed on a non-cacao diet showed that CSSV was still detectable after 144 hours. These unusually long durations for a pathogen currently classified as a semi-persistent virus have implications for the design of non-malvaceous barrier crops currently being considered for the protection of new cacao plantings.

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.

Transcriptomics and systems biology analysis in identification of specific pathways involved in cacao resistance and susceptibility to witches' broom disease

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

The spiny dogfish ('cacao-bagre'): description of an envenoming in a fisherman, with taxonomic and toxinologic comments on the Squalus gender

The authors report an injury caused by a spiny dogfish (Squalus sp) in a professional fisherman that was got hurt in the left hand for a spine in the dorsal fin of the fish and felt excruciating local pain for 6 h and manifested local edema and erythema. The sharks of the Squalus gender, in a similar way to the gender Heterodontus, present two spines in position previous to the dorsal fins, with channels presenting a whitish mass, composed of great and vacuolated cells that produce venom. The Squalus gender has a complex taxonomy, with five nominal species mentioned in Brazil: S. acanthias, S., blainvillei, S. cubensis, S. megalops and S. mitsukurii. The species associated to the injury belongs to the group 'megalops/cubensis'. A detailed study on the taxonomy and toxinology of the Squalus gender in Brazil would be of vital importance in the resolution of those problems and it would serve as subsidy for any other works involving their representatives, besides with aspects of envenoming that this gender can cause and that has rare citations in the literature. (c) 2005 Elsevier Ltd. All rights reserved.

La bolsa de café, azúcar y cacao y su incidencia en las exportaciones de América Latina y el Caribe = The coffee, sugar and cocoa exchange and its impact on exports from Latin America and the Caribbean

Incluye Bibliografía

Atividade antioxidante do extrato seco de cacau orgânico (Theobroma cacao): estudo de estabilidade e teste de aceitação de cremes acrescidos deste extrato

Conselho Nacional de Desevolvimento Científico e Tecnológico (CNPq)

Resistance of progenies of cacao to Ceratocystis wilt

Resistance of progenies of cacao to Ceratocystis wilt Seedlings from open-pollinated progenies of 20 clones of cocoa (Theobroma cacao) were inoculated with the fungus Ceratocystis cacaofunesta, the causal agent of Ceratocystis wilt, and their response was assessed based on the percentage of dead plants. Open pollinated progeny of clones TSH1188 and VB1151 were used as standards for resistance, while CCN51 and SJ02 for susceptibility. Contrasts between these benchmarks and the progenies studied were estimated and evaluated by Dunnett's t test (alpha = 0.05). The progenies showed different responses to C. cacaofunesta, and it was possible to classify them into three groups: resistant (FCB01, CSG70, BOBA01, VB902, TSH1188, VB1151, PS1319 and MAC01), moderately susceptible (HW25, PM02, FA13, PH15, M05 and BJ11) and susceptible (CCN51, FB206, PH16, SJ02, CCN10 and FSU77).

Studio della formazione e della composizione di aggregati solidi indesiderati in creme di nocciole e cacao destinate alla gelateria e conservate a basse temperature

Lo scopo di questa tesi, legato ad una collaborazione di ricerca industriale, è stato quello di stabilire la natura di aggregati solidi indesiderati che si formano in creme di nocciole e cacao, quando conservate, talora accidentalmente, a basse temperature, in particolare inferiori agli 0°C. L’obiettivo è stato quello di cercare di individuare le ragioni e gli ingredienti responsabili, con più probabilità, del fenomeno per poter dare indicazioni in merito alla formulazione o alla conservazione del prodotto prima e durante la commercializzazione. Sono state campionate due partite di creme di due differenti marche presenti in commercio. Una volta verificato per quali di queste creme e in che misura avesse origine la formazione degli aggregati solidi, si è proceduto ad un loro isolamento, mediante tecniche di estrazione solido-liquido, e successiva analisi gascromatografica degli acidi grassi. Anche per gli ingredienti delle creme di nocciole e cacao si è proceduto ad un’estrazione della componente lipidica ed ad una analisi gascromatografica degli acidi grassi. I risultati ottenuti sono stati elaborati, al fine di individuare gli ingredienti o le condizioni responsabili dell'insorgenza degli aggregati solidi indesiderati. La polvere di cacao è risultata, con più probabilità, l’ingrediente della crema di nocciola e cacao responsabile della formazione degli aggregati indesiderati, e questo ha suggerito la necessità di una verifica della qualità, anche in termini di cristallizzazione, di questo ingrediente, con particolare attenzione, ovviamente, alla frazione grassa (burro di cacao). E’ stato segnalato che un processo tecnologico di produzione non adeguato (tempera), in termini di temperature raggiunte e di mescolamento della crema, così come di conservazione del prodotto finale possono avere una importanza fondamentale nelle eventuali separazioni per condensazione di alcuni componenti della fase lipidica (agglomerati sferici).

La contribución de la producción del cacao orgánico a la resiliencia socio-ecológica en el contexto del cambio climático en el Alto Beni – La Paz

El cultivo del cacao en pequeña escala, sustento básico de muchas familias del Alto Beni, es afectado por los impactos del cambio climático. Para el desarrollo sostenible, es necesario que las fincas adquieran resiliencia: la capacidad de un sistema para reducir su sensibilidad hacia factores de estrés y perturbaciones, manteniendo su productividad, capacidad auto-organizativa, de aprendizaje y adaptación al cambio. Investigamos las diferencias en la resiliencia entre las fincas orgánicas y no orgánicas de cacao, y los rasgos significativos que inciden en la resiliencia socio-ecológica de los sistemas agrícolas del cacao. Definimos indicadores de resiliencia con expertos locales y productores durante un taller y con grupos focales. Los indicadores de la capacidad de amortiguación fueron: materia orgánica de los suelos, densidad aparente del suelo, e infestación con Moniliophthora perniciosa, diversidad arbórea, diversidad de cultivos, hormigas y fuentes de ingresos de las familias productoras. Los indicadores de auto-organización fueron: afiliación a organizaciones productoras, nivel de subsistencia, rendimientos de cacao e ingreso familiar anual. La capacidad de adaptación se evaluó indagando la cantidad de capacitaciones en que participaron las familias y la cantidad de fuentes de información que poseían. Entrevistamos 52 hogares: 30 orgánicos, 22 no orgánicos. Las fincas orgánicas en el área eran más diversificadas y rendían más. El ingreso familiar anual de las fincas orgánicas era sustancialmente mayor al de las no orgánicas. Probablemente el mayor rendimiento se debió principalmente a que los productores orgánicos participaron en más capacitaciones debido a su pertenencia a las organizaciones locales. Concluimos que las organizaciones locales de agricultura orgánica contribuyeron a crear resiliencia proporcionando servicios de extensión mediante el establecimiento de parcelas, creación de capacidades y seguros sociales

Surinamischer Cacao

Louise von Panhuys