Potting mix and phosphate fertilization for production of rooted Cocoa cuttings

Para avaliar o efeito de substratos e da adubação fosfatada sobre a produção de mudas de cacaueiro, bem como definir doses recomendáveis e nível crítico foliar de P, fez-se um experimento fatorial 5 x 5 + 1: cinco substratos (misturas de fibra de coco (FC) e Plantmax florestal estaca®), cinco doses de P no plantio (de 0 a 800 mg dm-3) e um tratamento adicional (P aplicado aos 30 dias). As parcelas iniciais e úteis continham, respectivamente, 27 estacas e 12 mudas (uma estaca/muda por tubete). A partir do 62º dia, aplicaram-se adubações semanais com N e K, e aos 120 dias, com P (20 mg dm-3), em todos os tratamentos. Aos 150 dias foram avaliados: diâmetro, altura, área foliar, massa de matéria seca da parte aérea e das raízes (finas e grossas), concentração e conteúdo de nutrientes na planta. A mortalidade das mudas não foi influenciada pelos tratamentos. A adubação com P em cobertura aumentou sua disponibilidade e sua absorção, mas não o crescimento das mudas. As variáveis biométricas e nutricionais responderam aos tratamentos, sendo os melhores resultados obtidos com 30 a 55 % de FC e doses de P entre 136 e 275 mg dm-3. O nível crítico foliar de P foi de 1,75 g kg-1.The effect of potting mix and phosphate fertilization on the production of rooted cocoa tree cuttings was evaluated and recommended rates and critical foliar P levels were determined based on a factorial 5 x 5 + 1 experiment: five potting medium (coconut fiber CF and Plantmax® mix), five P rates at planting (0 to 800 mg dm-3) and an additional P treatment (applied on the 30th day). Each plot contained 27 cuttings, of which 12 rooted cuttings were evaluated. From the 62nd day onwards, N and K fertilization was weekly applied as well as a P fertilization on the 120th day (20 mg dm-3), to all treatments. The diameter, height, leaf area, shoot and root (fine and thick) dry matter, nutrient concentration and content in plants were evaluated on the150th day. Cutting mortality was not influenced by the treatments. Phosphorus top dressing increased P assimilation and absorption, but not the growth of the rooted cuttings. The biometric and nutrition variables responded to treatments; best results were obtained with 3055 % of CF and P rates between 136 and 275 mg dm-3. The foliar critical level of P was 1.75 g kg-1

Cacao crop management zones determination based on soil properties and crop yield

The use of management zones has ensured yield success for numerous agricultural crops. In spite of this potential, studies applying precision agricultural techniques to cacao plantations are scarce or almost nonexistent. The aim of the present study was to delineate management zones for cacao crop, create maps combining soil physical properties and cacao tree yield, and identify what combinations best fit within the soil chemical properties. The study was conducted in 2014 on a cacao plantation in a Nitossolo Háplico Eutrófico (Rhodic Paleudult) in Bahia, Brazil. Soil samples were collected in a regular sampling grid with 120 sampling points in the 0.00-0.20 m soil layer, and pH(H2O), P, K+, Ca2+, Mg2+, Na+, H+Al, Fe, Zn, Cu, Mn, SB, V, TOC, effective CEC, CEC at pH 7.0, coarse sand, fine sand, clay, and silt were determined. Yield was measured in all the 120 points every month and stratified into annual, harvest, and early-harvest cacao yields. Data were subjected to geostatistical analysis, followed by ordinary kriging interpolation. The management zones were defined through a Fuzzy K-Means algorithm for combinations between soil physical properties and cacao tree yield. Concordance analysis was carried out between the delineated zones and soil chemical properties using Kappa coefficients. The zones that best classified the soil chemical properties were defined from the early-harvest cacao yield map associated with the clay or sand fractions. Silt content proved to be an inadequate variable for defining management zones for cacao production. The delineated management zones described the spatial variability of the soil chemical properties, and are therefore important for site-specific management in the cacao crop

Absorption of nutrients by soursop seedlings in response to mycorrhizal inoculation and addition of organic compost

The use of organic composts and the inoculation of arbuscular mycorrhizal fungi (AMF) are management alternatives in organic production systems. This study aimed to evaluate the effect of AMF inoculation (Acaulospora scrobiculata, Acaulospora colombiana and without inoculation) and organic compost of cacao bark (0 g dm-3, 5 g dm-3, 10 g dm-3, 20 g dm-3 and 30 g dm-3) on the mycorrhizal efficiency and nutrient uptake, in 'Morada' soursop seedlings. The experimental design was completely randomized, in a 3 x 5 factorial arrangement (AMF x organic compost), with four replicates. A higher mycorrhizal efficiency was observed for the A. colombiana isolate, with the addition of 0 g dm-3, 5 g dm-3 and 10 g dm-3 of organic compost to the soil, in relation to the A. scrobiculata isolate, which differed statistically at the doses of 20 g dm-3 and 30 g dm-3 of organic compost. The AMF inoculation promotes increases in the N, P, K, Zn, Cu, Fe and Mn contents, when compared to plants without inoculation. The organic compost exerts an effect on the inoculation, mainly on the absorption of P. The AMF inoculation, together with the organic fertilization, promotes the growth and nutrition of seedlings

Substratos e estaquia na produção de mudas de cacaueiro

O objetivo geral deste trabalho foi preparar substratos com base orgânica formada de composto do tegumento da amêndoa do cacau CTAC e serragens, misturados à areia, e utilizá-los na produção de mudas de cacaueiro por miniestaquia. Dessa forma, realizaram-se cinco experimentos. Inicialmente foram determinados modelos para retenção de água usando os métodos do funil de tensão e força centrífuga em equivalente de umidade e conclusão de que a centrifugação expressa valores da retenção de água próximos ou iguais àqueles encontrados com o funil. Em outro experimento sobre monitoramento químico verificou-se que a serragem pode ser usada sem pré-lavagem enquanto o CTAC depende desta prática. Ao comparar o crescimento de miniestacas com 4 e 8 cm de comprimento, enraizadas em meio arenoso e transplantadas para sacos de polietileno de 3,4 dm3, verificou-se não haver diferenças significativas entre os comprimentos testados. Outro trabalho cujo objetivo foi verificar a influência de substratos no enraizamento dos clones CCN-51, Cepec-2006, TSA -792 e TSH-1188, usando miniestacas de 4 a 6 cm de comprimento, concluiu que a serragem para o clone TSA -792 e a mistura serragem + CTAC para Cepec-2006 foram superiores ao TSH -1188 para a massa da matéria seca da parte aérea. Finalmente, realizou-se trabalho de caracterização física e avaliação do efeito de substratos à base de serragem e dois recipientes no crescimento de mudas de cacaueiro, no qual verificou-se que o transplante para sacos de 840 cm3 possibilitou maior crescimento das plantas comparado à manutenção em tubetes de 288 cm3 e que a serragem do município de Una-BA, misturada na proporção serragem: areia em 4:1 e 2:1 (v:v), pode ser recomendada para produção de mudas do clone TSH 1188.The objective of this work was to prepare substrates with an organic base formed from composted cacao hulls (CTAC), and sawdust mixed with sand and to use these in the production of cacao saplings from mini-cuttings. Five experiments were conducted. In the first experiment, water retention curves were determined for the substrates using two methods, tension funnels and centrifugation by moisture equivalent method. It was found that centrifugation exhibits retention water values close to or equal to those determined by the funnel method. The following experiment on the chemical properties of substrates verified that sawdust could be used without pre-washing whereas CTAC required rinsing. The comparison of the growth of mini-cuttings of 4 and 8 cm lengths rooted in a sandy medium and transplanted into polyethylene bags of 3.4 dm3 showed no significant differences between the two lengths tested. Other experiment whose aim was to verify the influence of substrates on the rooting of clones CCN-51, Cepec 2006, TSA 792 and TSH 1188, concluded that sawdust for clone TSA 792, and a mixture of sawdust and CTAC for clone Cepec 2006, performed better than TSH 1188 in terms of aboveground dry biomass production. The last work on the physical characterization and the evaluation of the effect of substrates and containers on the growth of the cuttings showed that transplanting into bags of 840 cm3 enabled greater growth compared to tubettes of 288 cm3. Furthermore, the sawdust derived from the Una-BA district mixed in pure sand at a ratio 4:1 and 2:1 (v:v) could be recommended for the production of cuttings of the clone TSH 1188.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Cocoa propagation, technologies for production of seedlings

Abstract The vegetative propagation in cacao has been used in Central America since the beginning of the last century. However, only from the end of the century this technique has been intensified in the state of Bahia, where vegetative propagation changes have increased the yield of cocoa growing areas, especially those using other technologies associated with clonal seedlings. The use of clonal garden to collect stems in nursery can reduce by 80% the space required for maintenance of stock plants. On the other hand, the buds obtained from orthotropic and plagiotropic shoots are used to improve the performance protocols and reduce production costs of seedlings. Among the current and future challenges in the production of cocoa seedlings emphasizes the somatic embryogenesis and rootstock with disease resistance. These technologies to increase the productivity of the crop and permit Brazil return to the exporter condition of cocoa beans, which does not occur for more than two decades

Caracterização física de substratos à base de serragem e recipientes para crescimento de mudas de cacaueiro

O objetivo deste trabalho foi realizar caracterização física e avaliar o efeito de substratos à base de serragem e dois recipientes no crescimento de mudas de cacaueiro. O delineamento experimental foi em blocos casualizados, em esquema fatorial 2 x 4 x 2. Os tratamentos foram obtidos da combinação de serragens originadas de dois locais: municípios de Una e Camacan, no Estado da Bahia, quatro proporções (v:v) de serragem e areia: 1:0; 8:1; 4:1 e 2:1 e dois recipientes de crescimento (tubetes de 288 cm³ e sacos de polietileno de 840 cm³). Antes do plantio, amostras dos substratos foram retiradas para análises físicas. Foram usadas miniestacas de 4 a 6 cm de comprimento do clone Trinidad Select Hybrid (TSH 1188). Inicialmente, as miniestacas foram tratadas na base com AIB 6.000 mg kg-1, em seguida foram inseridas em tubetes preenchidos com os substratos e mantidas em câmara de nebulização. Após quarenta dias, as miniestacas foram retiradas da câmara e transferidas para crescimento, em casa de vegetação, onde parte foi mantida nos respectivos tubetes e outra transplantada em sacos de polietileno de 840 cm³ preenchidos com os mesmos tratamentos. Após cinco meses, em casa de vegetação, as mudas foram avaliadas quanto à altura da planta, diâmetro do caule, massa da matéria seca da parte aérea e das raízes, número de folhas e área foliar das plantas. Na análise física dos substratos, verificou-se que a distribuição do tamanho de partículas foi diferenciada entre as serragens e a proporção de areia. As densidades seca, úmida e de partícula aumentaram, enquanto o teor de matéria orgânica e a porosidade total foram reduzidos pela adição de areia às serragens. O transplante de miniestacas enraizadas de cacaueiro, clone TSH 1188, para sacos com substrato preparado com serragem coletada no município de Una-BA, nas proporções serragem:areia 4:1 e 2:1, possibilitou maior crescimento das plantas, sendo,portanto, recomendados para produção de mudas.The aim of this work was to determine the physical characteristics of substrates of sawdust and to evaluate their effects on the growth of cacao cuttings. The experiment was carried out in random block, 2 x 4 x 2 with factorial design. The treatments were formed from two sawdust residues originated from the districts of Una (SU) and Camacan (SC), Bahia state, Brazil, four proportions (v:v) of sawdust and sand (1:0; 8:1; 4:1, and 2:1) and two growth containers (tubettes of 288cm³ and polyethylene bags of 840 cm³). The Trinidad Select Hybrid clone (TSH 1188) was used for micro-cuttings measuring between 4 and 6 cm in length. The cuttings were initially treated with IBA 6000 mg kg-1, after inserted in tubes filled with prepared substrates, and then maintained for 40 days in a vapor chamber for root development. Subsequently, the cuttings were transferred to the greenhouse where they either remained in their respective tubes or were transplanted into polyethylene bags and allowed to grow during five months. After this period, the following parameters were evaluated: plant height, stem diameter, above ground biomass and root biomass, number of leaves, and leaf area. Physical analysis of substrates confirmed that particle size distribution was determined by the proportion of sawdust and sand. Dry and wet particle density increased while organic matter content and total porosity decreased with the addition of sand. The transplanting of cuttings in bags used sawdust from Una-BA districts in the proportions sawdust: sand 2:1 and 4:1 facilitated more growth and can be recommending to propagation of cacao cuttings clone TSH 1188

Extrato da casca do fruto do cacaueiro como fertilizante potássico no crescimento de mudas de cacaueiro

Em função da importância da casca do fruto como principal resíduo da cacauicultura e as possibilidades de seu uso, este trabalho teve como objetivos realizar análise de nutrientes do extrato orgânico obtido por lavagem do composto de casca e avaliar seu efeito como fertilizante potássico no solo e no crescimento de mudas de cacaueiro. O ensaio foi realizado em casa de vegetação, com aplicação de doses de extrato via solo, cultivo em tubetes e mudas seminais de cacaueiro. O delineamento experimental foi em blocos casualizados, com três repetições, e a unidade experimental formada por nove plantas crescidas individualmente em tubetes. Os tratamentos foram 5 doses de K: zero; 125; 250; 500 e 1.000 mg de K dm-3 de solo. Após 120 dias da aplicação do extrato no solo, verificou-se que o pH, a saturação de bases e os teores disponíveis de Ca, Mg, K, Zn e Mn aumentaram, e o teor de Al e Fe diminuíram. Os resultados também evidenciaram que a dose de 1.000 mg K dm-3 de solo desequilibrou as relações K/Mg e K/Ca nas folhas com redução no crescimento das mudas. Mudas de cacaueiro apresentaram crescimento significativo em função de doses de K e, considerando a facilidade de produzir e aplicar o extrato da casca do fruto do cacaueiro, é possível usá-lo como fonte de K na produção de mudas de cacaueiro

Occurrence of Ochratoxin A in Brazilian cocoa beans

International audienceIn the present work studied the occurrence of Ochratoxin A (OTA) in dried beans from southern Bahia (Brazil) harvested in two periods of the year (early crop and harvest seasons) then fermented and dried under the sun. Nearly 92.5% of the cocoa samples presented OTA levels below the limits suggested by the European Community (2 μg/kg). The highest toxin content was found in fine and flavour cocoa beans harvested in the early crop. Ochratoxigenic species of the genera Aspergillus and Penicillium were isolated from the cocoa beans. Both harvesting time and production model influenced OTA content in cocoa. These results show that, according to the current world standards for Ochratoxin A levels, beans from southern Bahia give a good quality cocoa