Resumo em Inglês:

ABSTRACT Chlorophylls and carotenoids are the main photosynthetic pigments in plants, and photosynthetic potential can be used to determine the nitrogen fixation or cycling capacity of cover crops. Therefore, this study quantified and compared the content of photosynthetic pigments in Raphanus sativus and Vicia sativa by using two different methods, namely the extraction method and measurements with a portable chlorophyll meter, and determined whether the results of these two methods showed a significant correlation. Photosynthetic pigments were measured, using both methods, in a greenhouse and laboratory, at four developmental stages: the vegetative stages I (30 days after sowing [DAS]), II (60DAS), and III (90DAS), and the reproductive stage (150DAS). The determination of the photosynthetic pigment content in R. sativus and V. sativa, obtained from the extraction method and chlorophyll index, revealed significant differences depending on the developmental stage in both species. Furthermore, the contents of chlorophyll a, chlorophyll b, and carotenoids determined using the extraction method showed high coefficients of correlation with the total chlorophyll index determined using the portable chlorophyll meter. Therefore, the portable chlorophyll meter can be used for the accurate evaluation of the photosynthetic potential of Raphanus sativus and Vicia sativa, which also saves time and reagents.

Resumo em Inglês:

ABSTRACT Physalis pubescens L. is a UFP (unconventional food plant) that produces high quality fruits; however, in Rio Grande do Sul it is still considered a rare species. There is only few information regarding the characterization of these fruits in Brazil, and the main reports of this species are mainly focused on the pharmacology and agronomic conditions of the plant. The aim of this study was to analyze the physical and chemical composition, including bioactive compounds, of Physalis fruits obtained from a spontaneous culture of the southern region of Rio grande do sul. Soluble solids, total titratable acidity, vitamin C, moisture, ash, crude fiber, crude protein, lipids, carbohydrates, total caloric value, carotenoids, phenolic compounds, flavonoids and phenolic acids from pulp and seed were evaluated. It was observed that the fruit has acid characteristics (4.8%), in addition to a considerable presence of lipids (1.96%) and carbohydrates (10.85%), containing high content of carotenoids (171.36 µg β-carotene.g-1), phenolic compounds (142.83 mg.EAG.100g-1) and phenolic acids (38.55 mg EAC.100g-1). It was possible to observe that the fruits of Physalis pubescens are nutritious, presenting light acidity and they are a rich source of bioactive compounds.

Resumo em Inglês:

ABSTRACT The bioactive compounds and the antioxidant capacities of mangaba, mango and papaya oils were investigated. Determinations of fatty acid composition, tocopherol, phytosterols, phenolic compounds profile, total carotenoids, and antioxidant activity were carried out in the oils of mangaba, mango and papaya seeds. The analysis of antioxidant activity was performed by the methods DPPH•, ABTS•+, FRAP, and β-carotene/linoleic acid. Only essential fatty acid C18:2 was detected, in an average of 6.2%. In contrast, the main fatty acids quantified were oleic, palmitic, and stearic. The amount of phytosterols in mangaba (1951.7 mg kg-1), papaya (3540.3 mg kg-1), and mango (4565.7 mg kg-1) oils was higher than that of conventional oils, such as soybean oil. α-tocopherol was the main tocopherol found in all oils analyzed. Quantities of phenolic compounds were found only in mango seed oil. Papaya seed oil showed high quantity of total carotenoids (49.90 µg g-1). The possible use of the seeds studied to produce oils appears to be favorable. The information available in this study is of great importance for investigations regarding the use of vegetable oils as raw material for food, pharmaceutical, and chemical industries.

Resumo em Inglês:

ABSTRACT Bulk transportation of tomatoes is a step with high occurrence of mechanical impacts, leading to increased losses and reduction in the quality of fruits arriving at the industry and reaching the consumer market. The present study aimed to evaluate variations in physical-chemical parameters associated with the quality of tomato fruits, occurred during bulk transportation, using an approach based on principal component analysis. The experiment was conducted in the municipality of Morrinhos - Goiás, Brazil. Firmness, titratable acidity, total soluble solids, pH and mass loss were evaluated in the fruits at three times: during transportation on dirt road; after transportation on dirt road and during transportation on asphalt-paved road; after transportation on dirt and asphalt-paved roads and arrival at the processing yard. Principal component analysis was used to identify which physical-chemical attributes were most affected by transportation and generate quality indices of tomato fruits according to the physical-chemical attributes. Variation in the attributes was explained by the first three principal components, which had cumulative explained variance of 78.37%. Titratable acidity, soluble solids and mass loss had the highest correlations with the most representative principal component, thus being the most affected attributes during the bulk transportation of the fruits.

Resumo em Inglês:

ABSTRACT Due to the possibility of enhancing the physiological responses by modulating the architecture of coffee trees, the objective of the study was to analyze the leaf gas exchanges and biomass allocation of Arabica coffee cultivated with different numbers of orthotropic stems. The experiment was carried out in a plantation located in Santa Teresa-ES, Brazil, cultivated with spacing of 2.5×1.0 m, using the cultivar Catuaí Vermelho IAC44. The gas exchange rates were monitored along stages of the phenological cycle (2014/2015), following a split-plot scheme, 3×3 (number of orthotropic stems per plant in three levels: 1, 2 and 3; and the phenological stages in three levels: flowering, fruit formation and maturation). The allocation of biomass in the plagiotropic branches was also analyzed during the phenological stage of fruit maturation. The management of the number of orthotropic stems affected the photosynthetic responses and biomass allocation of coffee trees. Under the studied conditions, cultivating the plants with two orthotropic stems created conditions which promoted the photosynthetic responses. Keeping more stems promotes the availability of leaves per amount of produced fruits in the plagiotropic branches, allowing the plant to sustain the production with less metabolic wearing.

Resumo em Inglês:

ABSTRACT A better understanding of genetic diversity in cotton cultivars is needed to make the most of the genetic resources and guarantee continuing improvements in the breeding programs. Our objective was to evaluate the genetic diversity among cotton genotypes from the top breeding programs in Brazil and recommend hybrid combinations that would increase variability. The field experiments we conducted on three cotton genotypes from each of the following Brazilian breeding programs: EMBRAPA, MONSANTO DELTAPINE, FIBERMAX, IMA, TMG and UFU. Several phenotypic evaluations were carried out at V5, B1, full flower and full maturity. Moderate genetic divergence was observed among the genotypes from these breeding programs. Hybridization of the BRS 433 FL B2RF and FM 980 GLT genotypes would likely produce segregating populations with greater genetic variability, yield potential, lint yield and desirable fiber quality. Maturity, micronaire and fiber length were the strongest contributors to genetic divergence.

Resumo em Inglês:

ABSTRACT Multidimensional scaling is a multivariate analysis technique that can be used to exploit genetic diversity, aiming at the selection of Capsicum genotypes with desirable characteristics for in-pot ornamental purposes. This work aimed to select genotypes with ornamental potential within F4 populations of ornamental pepper plants. Three F4 families were used (17.18, 30.16, and 56.8). The genotype distance matrices were estimated based on qualitative and quantitative descriptors, separately, combining the standardized distances of Gower and Mahalanobis, respectively. The relation of the distance between genotypes was graphically studied through non-metric multidimensional scaling. Kruskal' Stress was used as the measured misadjustment of the nMDS solution. There is genetic diversity within the analyzed families, allowing to practice selection. The selection in family 17.18 of genotypes 6 and 32 is recommended, as well as in family 30.16 of genotypes 22 and 4, and family 56.8 of genotypes 15 and 36, since they present important characteristics for ornamental purposes. The selection of genotypes is more efficient when using mixed data since it provides a more complete genetic diversity in an improvement program.

Resumo em Inglês:

ABSTRACT Dry rot of yam (Dioscorea spp.) caused by Scutellonema bradys and Pratylenchus spp. has restricted yam production in Brazil. Plant-based products can be useful reducing nematode damages. The objectives of this study were to evaluate the nematostatic and nematicidal in vitro activities of pyroligneous extracts from Cocos nucifera, Syagrus cearensis, S. coronata, and Wodetia bifurcata palms against S. bradys and to evaluate the effect of C. nucifera pyroligneous extract in the treatment of yam tubers infected by S. bradys and Pratylenchus sp. under greenhouse conditions. The pyroligneous extracts obtained at pyrolysis temperatures of 400, 500, 600, and 700 ºC, and at different concentrations, were tested for nematode immobility and mortality in Kline slides. Cocos nucifera pyroligneous extract obtained at 400 °C and 1% concentration was tested on yam tubers, under different immersion periods. Six months after yam planting the nematode populations were evaluated. All pyroligneous extracts inhibited the mobility and caused mortality to S. bradys, however 100% inhibition of both variables was achieved at concentrations varying from 0.75 to 2%, depending on the pyrolysis temperatures. The reproduction factor was reduced in 43% by treating infected yam tubers with pyroligneous extract from C. nucifera.

Resumo em Inglês:

ABSTRACT The objective of this study was to evaluate substrates formulated with proportions of sewage sludge (SS)-solarized and SS-biochar in the production of seedlings of two indicator crops: lettuce (Lactuca sativa L.) and black wattle (Acacia decurrens Wild). The study was composed of two experiments conducted in greenhouse, in randomized block designs. The treatments consisted of five doses of SS-solarized and SS-biochar, combined with rice husk ash and vermiculite in different proportions (20:40:40, 30:35:35, 40:30:30, 50:25:25 and 60:20:20) and two commercial substrates (controls). Morphophysiological characteristics of the seedlings and the physico-hydric characteristics, pH and electrical conductivity of the substrates were evaluated. The pyrolysis process enhanced the characteristics of SS as a component of substrates, where the substrate with 20% of SS-biochar, 40% of vermiculite and 40% of rice husk ash, presented the better performance.

Resumo em Inglês:

ABSTRACT Several grafting methods have been developed, and bench grafting with stratification is the most widely used technique, except in Brazil, which is still in adaptation. The objective of this study was to evaluate for how long plant material can be stored before the grafting and the optimum temperature for stratification. Cultivar 'Paulsen 1103' was used as rootstock and 'Niagara Rosada' as scion cultivar. The storage period treatments were 0, 30, 60 and 90 days at the temperature of 3 ℃ and 95% of relative humidity. After the storage period, the branches were removed from the cold chamber, taken to grafting, and then placed at 19 °C and 24 °C for stratification. After 21 days of stratification, the vine grafts were planted in commercial substrate and left to grow for 160 days. The vine cuttings of cultivars Niagara and Paulsen 1103 can be stored in cold chamber at 3 °C for 90 days and, during this period, bench grafting can be performed at any time. However, the vines from cuttings stored in cold chamber for more than 30 days have better growth. It is recommended to stratify the vine grafts at 19 °C.