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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.

Abstract The time of formation of mangosteen seedlings propagated by seeds can be considered as the biggest difficulty in the seedling production system of this species. Considering that the use of humic acids as a growth promoter has been well documented in some species, the objective of this work was to evaluate the growth of mangosteen seedlings in response to the application of humic acid (HA) doses extracted from vermicompost (0; 2; 20; 40; 200 mg C L-1). Growth rate was determined using the following variables: stem diameter, plant height, number of leaves, leaf area, stem dry matter, leaf dry matter, shoot dry matter, root dry matter, total dry matter and Dickson quality index . The dose 150 mg C L-1 was the one that approached the maximum values and therefore should be recommended for the production of seedlings. The results at 240 days after planting (DAP) showed that the HA increased the growth of mangosteen seedlings, helping to reduce the time of seedling formation under conditions for permanent planting.

Abstract The aim of this study was to evaluate the effect of arbuscular mycorrhizal fungi inoculation (AMF - Acaulospora scrobiculata, Acaulospora colombiana and the mixture of these inocula) and doses of organic compost obtained from cocoa shell (0, 5, 10, 20 and 30 g dm-3) on “Morada” soursop seedlings. The experimental design was a randomized block with 4 blocks in a 5 x 4 factorial scheme (AMF x organic compost). After 120 days of growth, it was observed that AMF inoculation increased height, stem diameter and shoot, root and total dry biomass. Organic compost stimulated mycorrhizal colonization and the number of spores with the addition up to 10 g dm-3. Mycorrhizal inoculation promoted increases of P content in soursop leaves. Control plants did not show adequate response to doses of the organic compost applied and it was concluded that AMF inoculation combined with organic compost increased the growth and nutrition of soursop plants.

Abstract 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 mini-cuttings 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.

ABSTRACT 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.

Avaliou-se o enraizamento de miniestacas de gravioleira (Annona muricata L.), utilizando-se de estacas apicais e subapicais herbáceas coletadas em plantas cultivadas no campo e em casa de vegetação. O experimento foi conduzido em delineamento inteiramente casualizado, em esquema fatorial 4 x 2, sendo 4 tipos de miniestacas (apical herbácea do campo e viveiro, subapical herbácea do campo e de viveiro) e 2 níveis de reguladores de crescimento (0 e 6.000 mg kg-1), totalizando 8 tratamentos e 3 repetições, com 12 estacas por parcela. As miniestacas foram padronizadas com sete centímetros de comprimento e tratadas ou não com ácido indolbutírico, colocadas em tubetes contendo substrato comercial e mantidas em câmara de nebulização. Aos 80 dias após o estaqueamento, foi observado que as miniestacas subapicais e apicais de casa de vegetação e subapicais do campo apresentaram percentual de enraizamento de 97,3%, 88% e 88% respectivamente. Não foi detectado efeito da aplicação de AIB no enraizamento das miniestacas.

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.

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.

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 PThe 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

Abstract An obstacle to the production of mangosteen seedlings (Garcinia mangostana L.) is the long nursery time of approximately two years. Among other factors, the identification of a suitable substrate for seedling production from this species is a preponderant factor to reduce nursery time. This study aimed to evaluate the growth of seminal mangosteen seedlings grown in four different substrate compositions. Growth rate was determined using the following variables: stem diameter, plant height, stem dry mass, leaf dry mass, shoot dry mass, root dry mass, total dry mass and Dickson Quality Index (DQI). The substrate S1 (sphagnum turf and vermiculite) was superior to substrates S2 (pinus bark and vermiculite), S3 (pinus bark and coconut fiber) and S4 (soil) in all evaluated parameters. The principal component analysis separated the treatments into three response groups, in which S1 exerted the greatest influence on the growth variables, concluding that this one of the substrates tested was the most adequate for the formation of mangosteen seedlings.