Repositório RCAAP

This review aimed to approach the dynamics of pasture degradation, relating its causes and forms of recovery and/or renewal. Despite being based on extensive systems, Brazilian agriculture faces serious problems related to pasture degradation. The reduction in forage productivity directly affects the production system, having negative impacts on the economy and the ecosystem. Factors such as the choice of forage species, grazing management and the use of fire are the main factors responsible for the degradation of pastures in Brazil, causing an environmental and productive imbalance. However, it is possible to stop the progress of degradation and resume system productivity using pre-defined techniques in accordance with the objective of the production system. Furthermore, pasture recovery techniques are efficient for the resumption of productivity, and environmental protection, by helping to reduce greenhouse gases. Nevertheless, more research is needed to prove and consolidate pasture recovery techniques in the environmental, economic, and social scope.

The objective of this study was to perform the mapping of productivity and physico-chemical quality of fruit in orchard of 'Valencia' orange, as well as evaluating of the correlation between them valuables, aimed at precision agriculture. The study was conducted in a commercial orchard of 0.82 ha. The collections made on a sampling grid of 18 x 21 m, totaling 29 points. The parameters analyzed were: number of fruits, total mass fruit, average fruit weight, juice volume per plant, productivity, juice yield, longitudinal diameter and transverse of fruit, fruit shape, titratable acidity, total soluble solids and ratio. The data were subjected to descriptive statistical analysis and analysis of linear correlation of Pearson, and the results were spatialized in thematic maps. From the results it can be concluded that the number of fruits, juice volume per plant, total fruit weight and yield per plant showed high variability their values. The yield of juice, juice volume per plant and productivity are directly influenced by the number of fruits per plant. The mapping of harvest provided more details of the production area, demonstrating the importance of using tools of precision agriculture in commercial orchards.

In the last 30 years the Brazilian import of olive oil grew by 440%, which reflects the increase in consumption. Data on the perception and habits of consumption in relation to olive oil among Brazilian consumers, however, are still restricted. Research shows that erroneous choice criteria and myths still guide the purchase and consumption of olive oil in emerging markets, such as Brazil. The objective of this study is to verify consumption habits, selection criteria and preference of consumers in relation to olive oil. The methodology used was an online survey. The sample consisted of 291 consumers, who presented a family income and schooling higher than the Brazilian average, with 55% reporting daily olive oil consumption. The main results point out that price, origin, degree of acidity and brand are the most important criteria when choosing olive oil; the preferred origins are Portugal and Brazil; most would consume more olive oil if the product were cheaper and if they cooked more at home; only 5% stated they had good knowledge about how to use the product; and the main motivations for consumption are related to health and taste. The contribution of our study is to generate information about consumers that can be used by the agents of the production and marketing chain in educational and promotional actions, thus helping in the development of olive growing in South Brazil.

The quantification of the plant leaf area is a tool used in the analysis of plant growth, enabling infer important parameters of plant development. Thus, the objective was to compare methods of estimating leaf area (LA), both destructive and nondestructive in strawberry. As the standard method for obtaining the leaf area, used a scanner images (Scanner), evaluating the accuracy of methods for estimating leaf area of the product of length x width of the sheet, the sum of the product of the length x width of leaflets, leaf area integrators portable and bench, squares, fresh and dry weight of leaf discs. The data of the methods evaluated in comparison to the standard method, were analyzed by simple linear correlation, determining the coefficients of determination (R2) and correlation (r), which has been tested by t test. Except for the method of integrating portable leaf area, all methods for estimating leaf area evaluated, when compared to standard method showed accuracy and can thus be used to estimate leaf area in strawberry.

This study aimed to evaluate the influence of imidazolinone herbicides, usually applied to rice for control of red rice, on traits related to the physiology of winter crops. The experiment was installed in randomized blocks design, arranged in a 3 x 2 factorial scheme, with three replications. The first factor was composed by herbicide rates (0, 1 and 2 x the recommended dose) and factor B by the herbicides (imazethapyr + imazapic and imazapic + imazapyr) applied in pre-emergence of rapeseed, fescue, ryegrass, birdsfoot trefoil, white clover and vetch. At 60 days after emergence, shoot dry mass (g pot-1), photosynthesis rate, CO2 concentration in leaf mesophyll, consumed CO2, stomatal conductance of water vapor, transpiration rate, temperature gradient and water use efficiency were valuated. The mixture of imazapic + imazapyr caused death of all species tested, except vetch. The mixture of imazethapyr and imazapic caused reduction in dry mass for all plant species and plant death of rapeseed, independent of dose. Physiological traits were influenced by the action of herbicides and doses. Vetch performed better under application of the herbicides.

The objective of this work was to study the influence of different seeding rates and cultivars over flooded rice yield at the west border of Rio Grande do Sul State. The experimental design was a randomized blocks with four replicates. The treatments were arranged in factorial scheme 4 x 3, in which factor A was the seeding rate (40, 60, 80 and 100kg ha-1) and B the cultivars (BR-IRGA 409, Olimar and Puitá Inta-CL). The increase in seeding rate from 40 to 100 kg ha-1 reduces linearly the tilled number, filled, total grains for panicle and number of panicle per m2. The greater rice grains yield in cultivars Olimar and Puitá Inta-CL is obtained in seeding rate of 66 and 77 kg ha-1 respectively. On the other hand, the yield of cultivar BR-IRGA 409 was not influenced by seeding rate. The yield grain was greater in cultivar Puitá Inta-CL, except with the seeding rate of 80 kg ha-1, in which it was the second most productive cultivar.

This study aimed to evaluate the effect of lime and biofertilizer Supermagro on quality and yeld of pineapple ‘Perola’. The treatments were three rates (0, 50 and 100% of the recommended for pH 5.5) of dolomitic lime and three concentrations of biofertilizer (0, 5 and 10%). The results showed that the use of lime did not affect fruit size without crown, fruit mass with and without crown, total soluble solids, pH, titratable acidity, total soluble solid and titratable acidity ratio of the pulp, and yeld, but fruit size with crown diameters of the fruit and the contents N, P, Zn, Mn and Mg present in the leaf. The use of biofertilizer affected only the Zn present in the leaves. On the other hand, contrasts indicated that intermediate doses of lime and fertilizer, showed a trend of increase of average in most variables, especially in yeld. Present in leaf N presented a positive and significant correlation with fruit size with and without crown, fruit mass with crown, total soluble solids and titratable acidity of the pulp, and productivity, and Ca, with basal and medial fruit diameter.

The objective of this study was to evaluate the chemical quality of maize grains, which were subjected to intermittent drying at different air temperatures and stored for nine months. The grains were harvested at 17.9% moisture, tillage of the Experimental Station of the Universidade Federal do Rio Grande do Sul (UFRGS), and dried to moisture content of approximately 13% using flash dryer with use of LPG in air temperatures of 60, 70 and 80o C. Physical analysis of moisture and chemical Crude protein, lipid, ash, carbohydrate and oil acidity, Department of Animal Science, Faculty of Agronomy, UFRGS, from sampling performed after drying, and every three months for up to nine months of storage. The intermittent drying air temperatures up to 80°C did not cause quality of corn grains immediate damage. The quality losses were greater after six months of storage. Dried grains with temperatures of 80°C had the lowest quality loss during the nine months of storage. The lipid content was the chemical constituent that deteriorated most during storage. The longer the drying time is, the higher the latent damage in the chemical quality of maize grain during storage. The higher the grain moisture during storage, the greater the loss of quality of grain.

This study aimed to evaluate the physical and technological quality of maize grains subjected to drying with different stationary sources of air heating and stored for nine months. The grains were derived from the Experimental Station of the Universidade Federal do Rio Grande do Sul’s experimental farm, and dried to humidity of approximately 12% as follows: natural air drying, drying with the use of LPG and solar drying. The analysis of humidity, specific weight, thousand grains weight and integers were performed after sample drying and every three months up to nine months of storage and were conducted at the Plant Protection Department of the Federal School of Agronomy. The results allowed us to conclude that the greatest losses occurred after six months of storage for all treatments, mainly due to the attack of insects of the Sitophilus genus, showing that the three fuels used for drying proved to be viable in terms of keeping the grain physical and technological quality.

The objective was to evaluate the forage dry matter (FDM), leaf dry mass (LDM) and stem (SDM), leaf/stem ratio (L/S), leaf area index (LAI), height of cut (HC) and their correlations in winter forage at different densities. The experiment was conducted at the Universidade Estadual do Centro Oeste in Guarapuava - PR in 2012. The treatments were: 100% oats, 100% ryegrass, 50% oats and 50% ryegrass, 25% oats and 75% ryegrass, 75% oats and 25% ryegrass and 60% oats and 40% ryegrass. The experimental design was randomized blocks with five replications. There was a significant difference by Tukey test for LDM, where the density of 100% ryegrass produced 2477 kg ha-1, the L/S was 4.27 and the HC was 30.80 cm. For the other parameters showed no statistical difference. Correlations were significant by t test for LDM vs L/S (r = 0.86), LDM vs LAI (r = 0.89) and L/S vs HC(r = -0.88). The cultivation of ryegrass has its own advantages over cultivation intercropped with oats by offering greater LDM and especially the L/C be greater, besides being the first forage available for use with 68 DAS.

The aim of this study was to evaluate the growth, yield and nutrients uptake in lettuce with winery and poultry rearing waste as organic fertilizer. The winery waste was composted, while the poultry rearing waste was submitted for a thermic process to obtain a nutrient solution used in fertirrigation. The treatments were composed by different concentrations of plants organic fertilizer: T1, without fertilizer; T2, recommended mineral fertilizer; T3, 50% of recommended composted winery waste (CWW); T4, 100% of CWW; T5, 200% of CWW; T6, 50% of recommended poultry liquid waste (PLW); T7, 100% of PLW; and T8, 200% of poultry PLW. The organic fertilizer based on winery and poultry rearing wastes showed potential for organic fertilization in lettuce. The compost of winery waste should be used in recommendation of 100%. The poultry waste liquid solution should not use concentration higher than 100%, because there is no increasing in growth and yield of lettuce.

The occurrence of diseases is the main reason for reduction in common bean production in Brazil. Fusarium oxysporum f.sp. phaseoli and Sclerotinia sclerotiorum are the causative agents of important diseases of this crop. For the biological control to be successful for these and other diseases, the knowledge of the metabolites produced by the biocontrol agents such as Trichoderma spp. Is essential. From this point of view, this study aimed to characterize different isolates of Trichoderma spp. according to their metabolites production and verify the ability of these antagonistic isolates against the pathogens above mentioned. Twenty five isolates were tested, from three different species of Trichoderma. Their ability to produce hydrolytic enzymes, IAA and siderophores as well as their ability to inhibit the development of pathogens by the production of volatile metabolites and antagonism in paired culture were analyzed. All isolates produced chitinase, glucanases, proteases, IAA and siderophores. The production of volatile metabolites in vitro against F. oxysporum f.sp. phaseoli was effective with 24% of the isolates tested and 20% were able to inhibit the growth of S. sclerotiorum. In paired cultures, the reduction in growth for S. sclerotioum ranged from 67.5 to 100%, while for F. oxysporum f.sp. phaseoli reduction was from 29-50 %.

The covers can be used on fruits and vegetables in natura, because modifying the atmosphere around those avoiding physical and chemical changes. Thus, the present study aimed to evaluate the effect of filmogenic solution based on chitosan conservation at different times and temperatures of apples cv. Fuji. In addition to assessments rot incidence and qualitative changes the deposition surface was visualized in electron micrographs (SEM). The apples were coated with the solution in concentrations of 1 and 2%. Shortly after treatment, the apples were stored 0°C or 20°C for 5, 10 or 15 days plus two days to simulate commercialization. The use of filmogenic solution in apples stored at 0 °C maintained quality of apples regardless of concentration. Concentrations were effective in reducing weight loss and decay incidence. Apples coated with 2% solution showed better appearance providing more brightness in the fruit and maintaining ascorbic acid, acidity, the red color and soluble solids. The chitosan formed a protective layer homogeneous apples which was confirmed through electron micrographs.

The physical and mechanical soil quality is crucial for food production and inadequate management can lead to loss of sustainability and reduced productivity. The aim of this study was to determine the physical and mechanical properties of a Rhodic Kandiudox under different land use systems. The study was conducted in the experimental site of the Universidade do Oeste de Santa Catarina, in São José do Cedro, SC. The no-tillage system (NTS) was installed in the area two years before and the control area is characterized by native forest of the region. It was evaluated soil texture, bulk density, total porosity and pore size distribution, maximum soil density and the optimum water content, soil relative density and penetration resistance. The penetration resistance and the bulk density increased on no-tillage system. The optimum water content in a Rhodic Kandiudox is 0,21 kg kg-1 for native forest and 0,32 kg kg-1 for no-tillage system, and the maximum soil density is 1,20 g cm-3 for native forest and 1,35 g cm-3 for no-tillage system. The soil total porosity under NTS decrease compared to forest, increasing the volume of water available to plants.

Considering the pharmacological importance of oregano (Origanum vulgare L.) and peppermint (Mentha piperita L.), the development of in vitro propagation and cultivation forms may contribute to the insertion of these species into sustainable production systems with preserved genetic characteristics. The objective of this work was to verify the type of explant most promising for the in vitro establishment of oregano (Origanum vulgare L.) and mint (Mentha piperita L.). The treatments adopted were the introduction of three types of explants: nodal segments, leaf segments, and seeds. Each was individually introduced into test tubes containing 15 ml of the DSD1 culture medium. At the 7, 14 and 21 days after the in vitro introduction, the percentage of positive introduction response: budding to nodal segments, survival to leaves and germination to seeds were evaluated; contamination (fungi and bacteria), oxidation and number of shoots per explant. The experimental design was completely randomized, with three replicates, composed of 10 test tubes, in each treatment. The observed means were differentiated by Tukey's test 5%. The results indicate that for in vitro establishment of oregano only the nodal segments showed regeneration of plants. While for mint the nodal segment explants and seeds showed positive results. Further studies should be carried out to reduce fungal and bacterial contamination.

A study was conducted with the objective of evaluating the seminal characteristics of the Geophagus brasiliensis kept in captivity with and without hormonal induction. For that, 26 males were distributed among the following treatments: nine males without hormonal induction; nine males with hormonal induction of carp hipophysis extract (HC) and eight males with hormonal induction by human chorionic gonadotropin (HCG). The parameters seminal volume, semen color, sperm motility, sperm vigor, sperm latency time, sperm concentration and sperm viability were evaluated for the seminal characterization of males of different treatments. The data were submitted to analysis of variance with 95% confidence. The semen color was classified as milky white. Mean values for motility, vigor and sperm concentrations were: 94.44%, 78.75% and 63.88%; 4.44, 4.00 and 3.55; 5.10, 5.00 and 5.72 x 109 mL-1, for the non-induction, HCG and HC treatments, respectively. The sperm latency time ranged from 143.4 to 988.2 seconds and the sperm viability was 100% for all treatments. Analysis of variance did not show a significant difference between the effects of the different treatments on the evaluated parameters. Although the results demonstrated the artificial induction of males during the reproductive period is not necessary, other artificial reproduction protocols should be tested for G. brasiliensis envisioning the use of the specie commercially in aquaculture.

The study aimed to analyzed the vegetation from NDVI (Normalized Difference Vegetation Index) dynamics in Eucalyptus dunnii and Eucalyptus Urograndis comparing the NDVI generated from the digital numbers obtained from the conversion to apparent reflectance. The satelite images of TM/Landsat 5 sensor was used. Converting digital numbers (DN) to reflectance values and the calculation of the NDVI were obtained through spatial analysis operations Algebraic Geoprocessing Language (LEGAL). It was observed that NDVI values generated from the reflectances are greater than those determined by the DN. This observed difference is physically justified by the corrections made in the image of some parameters such as the minimum and maximum sensor radiances and mean stratospheric solar irradiance. E. dunnii presented higher values of NDVI when compared to E. urograndis, indicating that this is a useful tool when the objective is to identify the species, facilitating the management of the area.

The olive tree (Olea europaea L.) cultivation has intensified in the state of Rio Grande do Sul, which today has more than 3,500 hectares planted and 145 farmers, being the largest producer in the country. However, olive growers still face a number of difficulties, including those of plant breeding, especially those related to pest and disease management. The objective of this work was to generate basic and applied knowledge to the olive tree culture related to scale insects (Hemiptera; Coccoidea), control of potentially pest scale insects and control of Colletotrichum associated with anthracnose in olive tree to contribute for the development of culture in Rio Grande do Sul.

Native from Rio Grande do Sul natural pastures, Trifolium argentinense Speg. has sexual reproduction through aerial and subterranean seeds (amphicarpy) and vegetative reproduction by regrowth from storage roots. In this study the seeds produced at the soil-surface flowers, the depth effect and scarification on the aerial and subterranean seeds germination and the storage roots produced by plants derived from the two types of seeds were evaluated. The aerial (0.10 cm) and soil-surface (0.11 cm) seeds were similar in size, but smaller than the subterranean seeds (0.14 cm), with no significant variation in the production of the three types of seeds. Aerial and subterranean seeds scarified at and sowed 2.5 cm deep germinated better than the scarified and non-scarified seeds sowed on the soil-surface and at 7.0 cm, evincing a depth effect on seed germination. Although amphicarpic, T. argentinense first invests in the production of the storage roots making sure the cloning of specific genotypes and allowing the plants to persist vegetatively year after year without the need for regeneration by seeds in unfavorable environments for sexual reproduction, such as in Rio Grande do Sul natural pastures, where hard grazing and trampling can destroy the aerial part of the plants.  

The olive tree (Olea europaea L.) even though has both hermaphrodite and staminate flowers, it has mechanisms favoring the allogamy, being not advisable the monovarietals orchards planting. The pollination of olive trees is anemophilous, and produce a large amounts of pollen grains, dispersed throughout the atmosphere during the bloom. The economic viability of the olive oil is dependent of the fruit production and several factors can affect its fruit set. This study aimed understand the relationship of reproductive biology with fruit production in olive trees, in Southern Brazil. The study was carried out in a commercial olive grove located in Barra do Ribeiro (RS), whit seven year-old, in the years 2016-2017. The olive grove was formed for Koroneiki, Arbequina and Arbosana cultivars, spacing 5x7 m. It was evaluated the number of inflorescences per branch, number of flowers per inflorescence, number of hermaphrodite flowers, quality of pollen and the kind of pollination. ’Arbosana’ had the biggest number of flowers per inflorescence. ‘Arbequina’ had a higher percentage of hermaphrodite flowers than ‘Korneiki’ in both years, no differing of ‘Arbosana‘ in 2017. It has reduction of percentage of hermaphrodite flowers to ‘Koroneiki’ and ‘Arbequina’, in the second year. In the yeard 2017 there was reduction on the pollen viability, biggest in ‘Koroneiki’. Independent of cultivar, the open pollination provides bigger fructification. The fruit set in ‘Koroneiki’ was bigger than ‘Arbequina’. The measured parameters were not determinant for fruiting of the olive trees studied.