George Andrade Sodré

Substrato e adubação fosfatada para a produção de mudas clonais de Cacau

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.

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

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.

Cacao quality: Highlighting selected attributes

ABSTRACT World demand for cacao and the requirements for quality beans have increased every year. Research studies have developed standards for aspects of cacao quality that meet industrial criteria as well as international import and export legislation that is aimed at food security. This review focused on selected attributes of cacao bean quality. These attributes include the amount of acids, simple carbohydrates, proteins, amino acids, lipids, phenolic substances, and methylxanthines. Other attributes are bean moisture content, quantity of mineral nutrients, and presence of potentially toxic elements. Microbiological and organoleptic attributes are also of interest. Future research on cacao quality should focus on bean sampling, geographical location of plantations, genetic diversity of the cacao material, and standardized analytical methods for determination of organic and mineral substances.

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

Em funcao da importância da casca do fruto como principal residuo da cacauicultura e as possibilidades de seu uso, este trabalho teve como objetivos realizar analise de nutrientes do extrato orgânico obtido por lavagem do composto de casca e avaliar seu efeito como fertilizante potassico no solo e no crescimento de mudas de cacaueiro. O ensaio foi realizado em casa de vegetacao, com aplicacao de doses de extrato via solo, cultivo em tubetes e mudas seminais de cacaueiro. O delineamento experimental foi em blocos casualizados, com tres repeticoes, 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. Apos 120 dias da aplicacao do extrato no solo, verificou-se que o pH, a saturacao de bases e os teores disponiveis de Ca, Mg, K, Zn e Mn aumentaram, e o teor de Al e Fe diminuiram. Os resultados tambem evidenciaram que a dose de 1.000 mg K dm-3 de solo desequilibrou as relacoes K/Mg e K/Ca nas folhas com reducao no crescimento das mudas. Mudas de cacaueiro apresentaram crescimento significativo em funcao de doses de K e, considerando a facilidade de produzir e aplicar o extrato da casca do fruto do cacaueiro, e possivel usa-lo como fonte de K na producao de mudas de cacaueiro.

Características químicas de substratos utilizados na produção de mudas de cacaueiros

The aim of this study was to monitor the chemical properties of six substrates used in cacao propagation. The substrates received ten volumes (100mL each) of distilled water and the resultant leached were analyzed for pH, electrical conductivity (EC) and Na and K concentrations. The values of pH ranged from 5,0 to 8,0 in Plantmax® and composted cacao hulls (CTAC), respectively. It was confirmed that the CE of all substrates diminished after the first leaching volume. The results demonstrated that coconut fiber (FC) as well as CTAC should be used after an initial leaching pre-treatment. Yet while FC presented an initial EC greater than CTAC, the study showed that FC reaches the optimal value, 2.0 dSm-1, with fewer leaching volumes. Moreover, a positive correlation was found between EC concentrations of K and Na from FC (r=0.83 and 0.72; P<0.05) and CTAC ( r=0.98 and 0.99 ;P<0.05), suggesting that the concentration of K and Na are adequate indicators of EC of these substrates.

Propagação da gravioleira por miniestaquia

It was evaluated the rooting of cuttings of soursop tree (Annona muricata L.) using apical and subapical herbaceous cuttings collected from plants grown in the field and greenhouse. The experiment was conducted in a completely randomized design in a factorial 4 x 2, with 4 types of cuttings (apical herbaceous field and greenhouse, subapical herbaceous field and greenhouse) and 2 levels of growth regulators (0 and 6,000 mg kg-1 IBA), totaling eight treatments and three replicates of 12 cuttings. The cuttings were standardized with seven inches long and treated with 0 or 6,000 mg kg-1 IBA, placed in tubes containing commercial substrate and kept in a mist chamber. At 80 days after striking, it was observed that the subapical and apical cuttings of the greenhouse and subapical cuttings of field showed rooting percentage of 97.3%, 88% and 88% respectively. There was no detectable effect of IBA on rooting of cuttings.

Matrix management interfers in yield and quality of cocoa seedlings

The influence of two managements on yield and quality of plagiotropic mini-cuttings of four cacao clones was evaluated. The design was completely randomized in a 4 x 2 factorial scheme with 4 clones x 2 mother plant management (apical pruning and bending), with 10 replicates and one plant as experimental unit. Seedlings used were propagated by rooting of semi-woody cuttings of plagiotropic branches and at seven months of age, two seedlings of each clone were transplanted to 12 L pots filled with organomineral substrate. After transplantation, the apex of one of the plants was cut based on the count of the first six leaves from the apex. For bending, stems were folded and horizontally fixed. The first collection of mini-cuttings was performed 30 days after transplantation and the others during the following seven months. The yield of mini-cuttings was estimated during collections and part was used for rooting and quality evaluation of seedlings. After 90 days, 10 minicuttings of each clone were evaluated for quality using the Dickson quality index (DQI). Another 10 rooted mini-cuttings were transplanted to 1.5 L polyethylene bags and kept in greenhouse for another 120 days until final quality evaluation at 210 days. Data were submitted to analysis of variance and Tukey test at 5% probability. Shapiro-Wilk normality test and Pearson correlation analysis were performed. bending was more efficient in the average production of mini-cuttings especially for BN 34 clone. The Dickson quality index was correlated with root dry mass, at both 90 and 210 days, and the bending technique was responsible for the best DQI. Variable height was not adequate to estimate the quality of cocoa seedlings.

Avaliação do crescimento e qualidade de portaenxertos e mudas de cacaueiros

The experiment evaluated the growth and quality of rootstocks and grafted seedlings using cacao seeds of natural pollination, of the clone TSH-1188 and controlled pollination (TSH-1188 x CCN-10). Assays were carried to compare rootstock and grafted plants. The experimental design was completely randomized with the treatments formed by seed origin, one plant per plot and 30 replications. Pre-germinated seeds were planted in plastic tubes of 800 cm3 filled with substrate and after 90 days the plants were evaluated in plant length (CP) and stem diameter (DC). After 90 days were cut and evaluated: dry biomass of roots (BSR), stems (BSC), leaves (BSF), shoot (BSA), total (BST) and Dickson Quality Index (DQI). For grafting, 30 plants were separated by type of pollination and grafting with the clone BN-34. At 30, 45, 60, 75 and 90 days after grafting were evaluated for plant length (CPT; grafting and rootstock), trunk diameter (DMG) and number of leaves in the grafted stem (NFE). The evaluation of the second assay was performed 90 days after grafting where the plants were assessed for height and diameter, and then cut off to get BST, BSR and IQD. The results showed that seedlings from seeds of controlled pollination showed greater biometric uniformity expressed by IQD, in rootstocks as well as grafting plants with the BN-34 clone

GROWTH AND NUTRITION OF CACAO SEEDLINGS INFLUENCED BY ZINC APLICATION IN SOIL

Levels of Zn in tropical soils profoundly influences growth and nutrition of tree crops. Research was undertaken to assess the effect of soil Zn on growth and nutrition of clonal cacao tree seedlings of PH 16. Three acidic Oxisol soils differing in texture were used with nine doses of Zn (0, 1, 2, 4, 8, 16, 32, 48, and 64 mg dm-3). Rooted clonal seedlings were grown in plastic pot with 11 dm-3 of the soils at varying Zn levels for 240 days. At harvest growth (dry matter mass of leaves, stems, shoots, roots, and total) and nutrient concentrations were determined. The clonal cacao seedlings showed differences for production of dry matter mass and foliar nutrient concentrations for P, K, Ca, Mg, Mn, Fe, Zn, and Cu. There was Zn toxicity in all soils.