Wilson da Silva Moraes

Efeito da temperatura e do substrato na germinação de sementes de Caesalpinia ferrea Mart. ex Tul. (Leguminosae, Caesalpinoideae)

Caesalpinia ferrea Mart. ex Tul. is a tropical legume tree occurring in the Amazon region, commonly used as medicine plant and in urban landscaping. To make seedling production feasible the best temperature and substrate for seed germination were determined. Recently harvested seeds present 7.46% mean moisture content, 3.33% germination percentage and lower moisture gain during soaking, showing tegument dormancy. Mechanical scarification with 40 grit sandpaper was proven an efficient method to overcome the dormancy, resulting in higher germination percentage and water imbibition in scarified seeds. The germination percentage of scarified seeds was influenced by temperature, but not by substrate. Based on the mean germination time, it is recommended the temperature of 30oC and sand like substrate for faster germination of scarified seeds.

Chá: aspectos relacionados à qualidade e perspectivas

Black tea is one of the most widely consumed beverages in the world and it is prepared by the infusion of water with processed leaves of Camellia sinensis, which is cultivated in more than 30 countries, assuming a great socioeconomic importance. Several studies suggest that tea has protective effects against cancer and cardiovascular disease, due to the presence of polyphenols called catechins, which are oxidized enzymatically during the processing of the black tea, generating a mixture consisting mainly of theaflavins, theasinensins and thearubigins. The world production of tea has increased more than the demand, causing a drop of the price which, together with the increase in cultivation costs has shown a need for high productivity and quality. Nevertheless, there is not yet an efficient and accurate criteria to predict the quality of tea and agronomic practices which contribute to the increase in quality. In Brazil, the culture of tea is concentrated in the Ribeira Valley - SP, and almost all the production is exported. Despite the Brazilian product is not of high quality, it has achieved good prices in the international market. The Brazilian production, the production area and the number of tea industries are decreasing in recent years, clearly indicating the need for investments.

Efeito da luz no crescimento de mudas de Hymenaea parvifolia Huber

The objective of this work was to determine the effect of light intensity on the growth of Hymenaea parvifolia Huber seedlings as well as to infer on their degree of shade tolerance. Thus, an experiment was carried out in a completely randomized design, with four treatments (light levels): full sun (FS), 50% shading, 70% shading and natural shading (NS). The 50% and 70% shading levels were reached with the use of black polypropylene screens and the natural shading consisted of natural luminosity under a closed forest canopy. Each treatment had ten replications. Plants under 50 and 70% shading presented greater height, leaf area and leaf area ratio and few differences in dry mass accumulation, compared with plants kept under full sun. As a consequence, few differences were observed in the relative growth rate of the seedlings under these treatments. However, seedlings kept under natural shading showed lower relative growth rate and net assimilatory rate. The results as a whole showed that Hymenaea parvifolia was capable of adjusting itself to maximize the acquisition of light under very limiting conditions as that provided for natural shading and that the production of seedlings of this species can be carried out in nurseries under full sun and 50% or 70% shading.

Efeitos da luminosidade no crescimento de mudas de Caesalpinia ferrea Mart. ex Tul. (Leguminosae, Caesalpinoideae)

Caesalpinia ferrea is a species used a lot as a medicinal plant, for urban arborization and landscape design in the state of Amapa. Yet there is not much ecophysiological information available on it. Light is an important environment factor that controls processes associates with the accumulation of dry matter, contributing thus for plant growth. The object of this research was to study the effect of different luminosity levels on the growth of seedlings of this species. The seedlings were transplanted to plastics bags containing a mixture of soil and sand (2:1), which were maintained in the full sun, under artificial shade with reduction of 50% and 70% of the luminosity and under natural shade of a closed canopy of forest. The experimental design was completely randomized with five replicates. Seedlings submitted to natural shade showed strong growth inhibition. In the full sun, the seedlings presented higher net assimilatory rate (NAR), lower shoot/root ratio (SRR) and lower leaf area ratio (LAR). The results showed little difference in the growth and biomass allocation between seedlings kept in 50 and 70% shade; the seedlings submitted to this treatment presented higher values of SRR and LAR. This indicates plasticity which influences a possible increase in light capture and is important, therefore, to keep the seedling growth and survival under low light levels. The results as a whole showed morphological and physiological adjustment to different light levels in Caesalpinia ferrea.

Resíduos da agroindústria de chá preto como substrato para produção de mudas de hortaliças

This research was aimed at determining the effects of black tea industry residues as substrate on germination and growth of lettuce, tomato and cucumber. For such, germination and growth assays were carried out using, respectively, aqueous extract and different types of residues. In the germination assays, seeds were placed in trays on filter paper humidified with water or aqueous extract in the concentrations of 1, 5 and 10%. In the growth assays, seeds were placed in trays containing: 1. vermiculite; 2. decomposed residue plus vermiculite; 3. decomposed residue and 4. crude residue washed plus vermiculite. The decomposed residue was obtained from crude residue decomposition process and the crude residue washed from crude residue washing in water. For the assays were adopted the randomized completely experimental design with four treatments and four repetitions of thirty seeds each. The results indicated that aqueous extract inhibited the seeds germination and seedlings growth of lettuce, tomato and cucumber. The crude residue washed plus vermiculite also reduced the seedlings emergency. On the other hand, the decomposed residue and decomposed residue plus vermiculite stimulated the seedlings emergency and growth. The decomposition process possibilited the use of black tea industry residue as substrate for seedlings growing of vegetable crops.

Incidência de fungos em pós-colheita de banana 'Prata anã'(Musa AAB)

ABSTRACT The objetive of this work were to determine the occurrence andfrequency of fungus in ‘Prata ana’ banana and to elucidate the causalagent of post harvest rots on fruits from Jaiba, Minas Gerais, Brazil.Two isolation methods were used: diluition in placs from whashedgreen fruits and direct of mature fruits. The fungus Colletotrichummusae, Trichoderma harzianum, Fusarium equisetii , Penicillium sp., Aspergillus parasiticus, Trichothecium roseum, Colletotrichumacutatum, Alternaria sp., Cladosporium musae and Curvularialunata were the more frequentilly associated to fruits. The funguspathogenicity were tested by substituition of green fruits pell discs for RESUMO Este trabalho teve por objetivo determinar a ocorrencia e a frequen-cia de fungos em banana ‘Prata ana’ e elucidar o agente causal daspodridoes em pos-colheita de frutos provenientes do norte de MinasGerais. Dois metodos de isolamento foram adotados: diluicao em pla-cas, a partir da lavagem de frutos verdes, e direto de frutos maduros. Osfungos

Termoterapia e quimioterapia de banana 'Prata-Anã' associadas à temperatura de armazenamento no controle de podridões em pós-colheita

The objective of this study was to evaluate the effects of thermotherapy (56 oC for 6 min) and chemotherapy (propiconazole 250 ml.l-1) associated with storage temperature (environmental temperature, 18 oC and 13 oC) in the rot control of postharvest banana (Musa spp.) fruits. Treatments have shown significant differences in the percentage of peel area with lesions per fruit, weight loss and external peel coloration in all storage temperatures. Chemotherapy and the combination of both thermotherapy and chemotherapy avoided rot manifestation in the three storage temperatures. Thermotherapy, after 15 days, reduced the percentage of peel area with lesions per fruit from 98% to 11% at environmental temperature, from 8% to 7% at 18 oC and 7% to 0% at 13 oC, being most efficient at 13 oC. Non-treated fruits lost 25%, 10% and 3% of their weight and got color 7, 5 and 1 at environmental temperature, 18 oC and 13 oC respectively, after 15 day. Fruits treated with thermotherapy and chemotherapy lost 24, 11 and 5% and 20, 10 and 3% of weight and got color 4 and 3,5, respectively. The conservation period was extended to 18, 24 and 45 days at environmental temperature, 18 oC and 13 oC, respectively. The combination of methods avoided rot manifestation, reduced weight loss and maintained external peel coloration and fruit quality.

Eficiência de fosfitos no controle da podridão da base do estipe em mudas de pupunheira

The exploitation of heart of palm in Brazil is no more an extractive activity; it is becoming a commercial production due to the planting of palm trees such as peach palm (Bactris gasipaes Kunth var. gasipaes Henderson). The stem base rot (SBR) caused by Phytophthora palmivora has emerged as an important disease, which may limit the peach palm production in many regions. This disease occurs in young and adult plants. This study aimed to evaluate the efficiency of preventive and curative application of phosphites on SBR incidence and its severity in peach palm seedlings under greenhouse conditions. Three experiments were carried out, as follows: I - preventive and curative effect of phosphites, following factorial scheme 6 x 2 (phosphites x application time); II - effect of preventive application of potassium phosphite, following factorial scheme 6 x 4 (number of applications x evaluation periods), and III - Effect of preventive and curative methods and application periods of potassium phosphite, following a factorial scheme 2 x 2 (application forms x dosage). Disease severity was assessed at 28 days in experiment I and III in the experiment, while in experiment II was evaluated at 7, 14, 21 and 28 days after inoculation, based on descriptive scale with a scale from 0 to 4. Treatments were carried out in a completely randomized design with 10 repetitions of one seedling for each repetition. Data were submitted to variance analysis and when treatment means were significant by F test (p < 0.05) they were compared by Tukey test at 5% of probability. From the results obtained, it was concluded that potassium phosphite have better control between phosphites tested, and when applied preventively at 2.5 mL.L-1 with 3 applications and dosage of 5.0 mL. L-1 with 2 or 3 applications significantly reduced the incidence and the severity of SBR in peach palm seedlings. But, when applied as curative had no effect, regardless of the dose or the number of applications. Since the best time for severity assessment of SBR was 21 days after inoculation of Phytopthora palmivora.

Propagação de Camellia sinensis: efeito do genótipo, estaca, substrato, recipiente e ácido indolbutírico

It has been reported that Camellia sinensis has a low ability to emit roots, stimulating basic studies of propagation by cuttings. Therefore, this study aimed to quantify the rooting potential of different genotypes and the effect of the position of cuttings of the branch and basal injury, of the substrate, recipient size and indolebutyric acid on rooting of semi hardwood cuttings of this species. Stems were collected from three genotypes, IAC 259, F15 and Comum, grown in Pariquera-Acu, Sao Paulo state, Brazil, in winter 2010 and prepared cuttings, with one bud and one leaf, which were kept in a nursery with 70% of shading. The cuttings of basal and median position on branch were the most suitable due to lower mortality and greater rooting capacity. The basal injury does not affect mortality and the rooting of cuttings, but induces the formation of callus. There were also no differences in mortality and rooting of cuttings when they were kept in containers with 50, 90 and 120 cm3. The presence of incision at the base of cuttings, along with treatment with 10 g L-1 IBA and soil as a substrate promoted the highest percentage of rooting. However, even in this condition the average mortality of the cuttings was 42%. The rooting potential of Comum genotype was superior to the IAC 259 and F 15.

EFFECT OF DEFOLIATION ON THE YIELD AND QUALITY OF ‘PRATA COMUM’ BANANA FRUITS

Com o advento da Sigatoka negra nos bananais comerciais do Vale do Ribeira, SP, o monitoramento da severidade e o controle quimico da doenca em variedades suscetiveis passaram a ser mais frequentes, a fim de evitar a perda de folhas. Dessa forma, foi realizada a simulacao da desfolha causada pela doenca, com o objetivo de avaliar o seu efeito na producao e na qualidade dos frutos da bananeira ‘Prata Comum’ (AAB), em funcao do periodo de formacao e da posicao da penca no cacho. O delineamento experimental foi inteiramente casualizado em esquema fatorial 2x11 (dois periodos de formacao do cacho x numero de folhas na floracao (6 a 16), com seis repeticoes. No Periodo 1, a floracao ocorreu em 15/04/13 e no Periodo 2, em 07/01/14. Apesar de, no Periodo 1, a massa do cacho ter sido mais elevada, no Periodo 2 observou-se temperaturas medias diarias maximas e minimas, precipitacao e radiacao mais elevadas. Independente do periodo de formacao, o numero de folhas na floracao afetou a massa do cacho, que variou de 18 a 23 kg planta-1. A desfolha afetou o tamanho dos frutos da penca 1 e ultima penca do cacho, mas nao a variacao de tamanho dos frutos em funcao da posicao que o mesmo ocupa no cacho e caracteristicas fisico-quimicas.