Repositório RCAAP

The objective of this work was to evaluate the effects of splitting in three different doses of phosphorus and potassium, combined with each other, and it was applied fertirrigation in watermelon crop, and to evaluate their effects on fruit quality. The statistical was in a complete randomized block design, and the treatments were arranged in a factorial scheme (3 x 3) in subdivided splits, resulting in 9 treatments with tree replications, totaling 27 plots in the experimental area. In the horizontal plots the three doses of phosphorus fertilization (100, 150 and 300 kg.ha-1 of P2O5) were randomly allocated, and in the subplots the three potassium doses (50, 100 and 200 kg.ha-1 of K2O), were applied in fertirrigation. The cultivar used was Crimson Sweet. Seventy-Six days after planting (DAP) the biochemical characteristics of watermelon fruits were evaluated: total soluble solids (TSS), total treatable acidity (TTA) and potential of hydrogen (pH). According to the results, it was verified that only the chemical value of the TSS fruits, presented significant statistical differences between the studied doses because of the different source of fertilization K and P increased the soluble solid contents, the content of reducing sugars, and decreased pH. It was observed the different doses of K and P did not influence in the fruit quality parameters when it was analyzed separated: TTA and pH but the TTA values are according to consumer market standards. The best doses in order to economy of fertilizer were (150 kg ha-1 de P2O5 e 50 kg ha-1 of K2O).

The use of crop practices to reduce the weed community is an ally to integrated weed management. Given this, the study aimed to identify a composition and weed infestation in a soybean area under different predecessor crops implanted in different years. The experiment was carried out in the 2019/2020 harvest in Dourados, MS. The experimental design was a randomized block with nine treatments. The treatments were composed of autumn-winter crops. The area with predecessor cultivation: corn-Brachiaria intercropping; cowpea beans; single corn; an area with predecessor cultivation of Brachiaria as pasture for one year; two years; three years; four years; five years, and six years. All treatments were followed by soybean cultivation in the 2018/2019 harvest and an intercropping with corn and Brachiaria in the 2019 off-season harvest. There was a difference in the absolute weed infestation between the evaluated areas. Treatments with corn and cowpea had greater weed infestation. However, areas with pasture or intercropping with corn and Brachiaria showed less infestation, especially in areas with Brachiaria grown in the off-season for more than two years. The weed species composition differs between the areas evaluated. The implantation of a corn-Brachiaria intercropping in the off-season under a crop rotation system, especially in areas with Brachiaria grown in the off-season for more than four years, reduces the weed infestation.

Ocimum selloi is a plant used in traditional medicine as a tea; however, no studies have reported the biological activity of the aqueous extract of this plant. This study aimed to evaluate the cytotoxicity, genotoxicity, and mutagenicity of two concentrations of an aqueous extract prepared by infusion of leaves from O. selloi using the Allium cepa model. The O. selloi infusion contained 107.1 ± 1.27 mg GAE g-1. In the A. cepa test, the concentration of the extract influenced the germination index; for 1.0 mg mL-1, it was 60.78% and for 5.0 mg mL-1, it was 51.14%. The evaluation of root development also showed differences between the two concentrations and the negative control, and differences in mitotic index were observed between the concentrations and the negative control; the concentration of 1.0 mg mL-1 showed an index of 4.1%, and for 5.0 mg mL-1 it was 3.7%. An index of chromosomal changes of 0.1% was observed for a concentration of 5.0 mg mL-1. The A. cepa test therefore showed that the studied concentrations did not cause deformations in cells, cell death or mutagenic alterations.

Pepper trees have great ornamental value due to the varied colors of their fruits. Thus, the objective was to evaluate the Pyramid cultivar's production in different cultivation environments using benches with reflective material. The experiment was carried out in two protected environments: a) agricultural greenhouse with 42-50% shade screen under the plastic film and b) agricultural screen with black monofilament screen with 18% shade. Inside the environments, the production system was tested with and without reflective material on the cultivation bench. The experiments were conducted in a completely randomized design, with four replicates and six plants per plot. Joint analysis was used to compare environments. At 45, 60, and 75 days after transplantation, plant height, stem diameter, number of leaves, canopy area, and number of fruits were evaluated. The agricultural greenhouse with a 42/50% shade screen under the plastic film provided the formation of higher plants with greater stem diameter, greater number of leaves and fruits, and greater top diameter than the screen with 18% shading. The reflective mirror material showed positive results only for plant height.

The plant environment in the production of Achachairu (Garcinia humilis) seedlings aims to obtain quality plants for orchards' formation. The present study aimed to evaluate reflective materials on benches and fruit seeds harvested from different plant positions to produce Achachairu seedlings. The reflective materials used under the cultivation benches were aluminum foil, "fake sequin" fabric, mirror, and tetra pak®. The fruit collection positions in the plants were at the top, median and bottom. The largest seedlings were obtained on the bench with reflective material of Tetra Pak®; however, in this material, there was a greater relationship between the height and diameter of the seedlings' neck, which is not desired for quality seedlings. The largest number of sheets was observed on the benches with reflective material of Tetra Pak® and "false sequin" fabric. The lowest dry masses of the root system and the lowest Dickson quality indexes were obtained from seedlings grown on the bench with reflective mirror material, forming lesser quality seedlings. The fruit collection place in the matrix plant did not influence the seedlings' quality. The use of reflective material on the bench is not recommended for the cultivation of Achachairu seedlings.

Forage seeds often have a low germination percentage due to their seeds' dormancy, such as seeds of the genus Urochloa. Chemical scarification is chosen to overcome the dormancy, yet the seed's vigor level is not taken into account. On this wise, the method can harm the seed's quality. In this context, the study aimed to investigate the appropriate scarification period in brachiaria seeds and how the lot's thermal stress can affect this result. The experimental design was completely randomized, arranged in a 3x4 factorial scheme, designated by thermal stress (0, 24, and 48 hours) and periods of chemical scarification with concentrated sulfuric acid (0, 5, 10, and 15 minutes), with four repetitions. After scarification of the treatments, the seeds were evaluated for germination and vigor criteria. Scarification for 5 minutes is enough to express the quality of Urochloa brizantha cv. MG-5. This technique is not recommended after the seeds are severely stressed by temperature and humidity.

As substâncias químicas utilizadas no condicionamento fisiológico pode ser uma das técnicas utilizadas para reduzir os estresses causados pelas adversidades que acometem as sementes de milhos durante a emergência e o estabelecimento da cultura. Objetivou-se avaliar diferentes substâncias utilizadas no condicionamento fisiológico de sementes de milho para a superação de estresses abióticos no momento da germinação e emergência. O delineamento experimental foi inteiramente casualizado em esquema fatorial 2 x 5, sendo constituído de dois lotes de sementes, e quatro agentes químicos utilizados no condicionamento fisiológico, mais a testemunha. As sementes foram submetidas a diferentes estresse abióticos: baixa temperatura, hipóxia, estresse salino e restrição hídrica. O condicionamento fisiológico de sementes através da imersão direta, no período de 18 horas e com ambas as substâncias se mostrou de modo geral, um método promissor para superar efeitos deletérios abióticos encontrados a campo no momento da germinação. A utilização de nitratos via condicionamento fisiológico é uma alternativa para promover efeitos benéficos perante a situações de estresse. O condicionamento fisiológico proporciona maior velocidade de emergência, independente da substância utilizada, sem interferir no desenvolvimento inicial de plântulas.

Campomanesia adamantium (Cambess.) Berg O. is a native of Savanna, popularly known as gabiroba, guavira, or gabiroba-do-campo, and has many uses, with its fruit being consumed fresh or processed. This study aimed to evaluate different doses of phosphorus and nitrogen in the initial development of gabiroba (Campomanesia adamantium) cultivated in pots. Five doses of phosphorus (0, 100, 200, 300, and 400kg ha-1 of P2O5) and three doses of nitrogen (0, 100, and 200 kg ha-1of N) were tested. The experimental design used was completely randomized in a 5x3 factorial scheme with six replications. The evaluations were carried out 120 days after plant emergence, and the variables analyzed were stem diameter, plant height, and number of leaves. Data were subjected to analysis of variance and F-test. The means were compared by the Tukey test at p<0.05. Regression analyzes were adjusted for phosphorus doses. The gabiroba responds significantly to the addition of phosphorus, with the dose of 400 kg ha-1 of P2O5 providing the highest height and the dose of 300 kg ha-1 of P2O5 providing the greatest stem diameter and the number of leaves. Up to 120 days old, gabiroba seedlings do not respond significantly to nitrogen fertilization.

This study aimed to evaluate the effect of nitrate salts and a growth regulator on seed conditioning. Subsequently, the responses of the influence of the leaf application of paclobutrazol (PBZ) and nitrogen on the quality of seedlings of Capsicum frutescens L. were evaluated. Two experiments were carried out. The first experiment was conducted in a completely randomized design to evaluate priming, as follows: T1 – control, T2 – control (water), T3 – 0.2% calcium nitrate, T4 – 0.2% potassium nitrate, T5 – 0.1% calcium nitrate + 0.1% potassium nitrate, T6 – PBZ, and T7 – PBZ + 0.1% calcium nitrate + 0.1% potassium nitrate. The second experiment was carried out in a completely randomized design in a 2×5 factorial scheme consisting of priming (absence and presence of calcium nitrate) and leaf application of growth regulator, as follows: control (water), PBZ, PBZ + 1% nitrogen (calcium nitrate), PBZ + 1% nitrogen (urea), and PBZ + nitrogen (0.5% calcium nitrate + 0.5% urea). Physiological conditioning with a solution of 0.1% calcium nitrate increased the germination and seedling emergence rate and resulted in seedlings with a higher shoot length at 33 days after sowing (DAS), but seedlings at 50 DAS showed no differences in growth with its use. Leaf application of 0.1% paclobutrazol provided pepper (C. frutescens L.) seedlings with better distribution in growth according to the Dickson quality index.

Lettuce cultivation is an activity of great economic importance; therefore, the use of techniques for better use of space and better-growing conditions should be evaluated. The objective of this study was to evaluate the development and yield of garden lettuce grown under different soil coverings and plant spacing. The study was conducted in an experimental area located at the School of Agronomy of the Federal University of Goiás, in the city of Goiânia, Goiás. The experiment was conducted in a randomized block design with subdivided plots in four replications. The plots consisted of three soil coverings (soil without cover, straw, and plastic cover) and the subplots in three planting spacing (PS1 = 25 x 20; PS2 = 25 x 25; PS3 = 25 x 30 cm), totaling nine treatments. The evaluations occurred when the plants presented their complete development, being evaluated: plant diameter, fresh head mass, stem mass, number of leaves, stem height; stem diameter; relative chlorophyll index; yield; and utilization, corresponding to the percentage of fresh marketable mass. It was found that the use of soil cover can favor the densification of lettuce cultivation. For cultivation on soil without cover or with the use of plastic as a cover, the cultivation spacing must be greater.

The objective was to evaluate the effect of stocking density on productive performance, carcass characteristics, productivity, bone development, and profitability of Ross 308 broilers. A completely randomized experimental design with four stocking densities (10, 12, 14, and 16 birds m-2) and four replicates, and the subplots the bone collection ages (7, 14, 21, 28, 35, and 42 days old). The variables analyzed were live weight at 21 and 42 days, weight gain, feed intake, and conversion in the accumulated periods from 1 to 21 and 1 to 42 days. Weights of carcasses, commercial cuts, edible viscera, abdominal fat, productivity, production efficiency index, viability, and profitability were evaluated. The length, thickness, weight, and Seedor index of long bones (tibiotarsus and femur) were also evaluated. The yield was higher for densities of 14 and 16 birds m-2. The thickness of the tibiotarsus was lower in the density of 12 birds m-2. The increase in the stocking density of 10 or 12 birds m-2, to 14 birds m-2 allows greater productivity per area, without compromising the productive performance, such as carcass characteristics and the animal's bone development, besides being the breeding density with the highest profitability, considering the welfare of Ross 308 broilers.

This study aimed to evaluate the in vitro interference of different culture media, Czapek Dox Agar, Nutrient Agar, Starch Casein agar, Malt Extract Broth Base, Nutrient Broth, and the medium containing Peptone, Malt, Agar and crushed peach palm pulp (Bactris gasipaes) and tucumã (Astrocaryum aculeatum) on the fungus Leucoagaricus gongylophorus and the parasitic fungus Escovopsis sp. growth. The fungi were inoculated in different culture media and then kept in acclimatized chambers at 28 ºC in the dark for 42 days, being analyzed at weekly intervals, totaling six evaluations. Fungal colonies were evaluated considering the factor "f" (cm), obtained from the product between the width (W) and length (L) of the diameter of the colonies (f = W x L). The results showed that the symbiotic fungus and the leafcutter ant parasitic fungus showed a growth increase compared to the media provided in the plates, and the media added with tucumã peel, tucumã peel+pulp, fresh peach palm, and cooked peach palm had a significant effect in the L. gongylophorus fungus development. However, these treatments were not promising for the Escovopsis sp. fungus compared to other culture media.

The competition between soybean and weeds affects crop development due to reduced resources such as water, light, and nutrients, leading to yield losses. Thus, the study aimed to evaluate quantitatively and qualitatively, through phytosociology and seed bank, the weed presence in a soybean cultivation area with different predecessor cover crops. The experiment was installed under no-till system conditions using a randomized block design with nine treatments and three replications. The treatments were composed of the following cover crops, sorghum (Sorghum bicolor), crotalaria (Crotalaria ochroleuca), millet (Pennisetum americanum), Urochloa ruziziensis, U. brizantha cv. Piatã, fodder radish (Raphanus sativus L.), U. brizantha cv. Xaraés, millet + fodder radish, and fallow. The soybean crop was established on the cover crops in the 2019/20 harvest. Soybean characteristics, the seed bank, and weed phytosociology were evaluated. The highest soybean yield was obtained with U. ruziziensis as predecessor cover crop, reaching 4530 kg ha-1. It was concluded that the following cover crops, sorghum, crotalaria, and millet, were the ones that most suppressed the soil weed seed bank. Contrarily, the fallow provided the greatest viable seed number. The weed species Eleusine indica, Digitaria insularis, and Cenchrus echinatus had higher phytosociological values in all treatments.

Nitrogen (N) is a nutrient associated with the development of plant shoots, which makes it a vitally important element for the maintenance and sustainability of pasture. The goal of this study was to evaluate the effects of nitrogen fertilization on the productive and nutritional traits of Urochloa brizantha Paiaguás, as well as the efficiency of digital imaging and the use of a chlorophyll meter in obtaining green color indices. The experiment was conducted in the field on the Escola farm at the State University of Goiás, located in São Luís de Montes Belos, GO. A randomized-block design with five treatments and four replicates was adopted. Treatments consisted of four N rates (0, 75, 150, 300, and 600 kg ha‒1) in the form of ammonium sulfate. The grass responded up to the N rate of 374 kg ha‒1 for production-related traits, such as plant height, number of tillers, and shoot dry matter. Maximum dry matter yields were 21,225 and 13,710 kg ha‒1 yr‒1 for the first and second cycles, respectively. Both the chlorophyll meter and digital imaging were efficient in indicating plant N nutritional status. Paiaguás grass responds to N similarly to other Urochloa brizantha cultivars.

The choice of the cultivation environment interferes with the whole vegetable development because of the micro-meteorological conditions in which the plants are cultivated, and the use of technologies with reflective material aims to complement the production in both quantity and quality. In this sense, the objective was to analyze the growth and productivity of Biquinho pepper (Capsicum chinese) plants cultivated in two types of protected environments and benches with reflective material. The experiment was conducted in a completely randomized design, with five repetitions. A plastic greenhouse with 42% shading and agricultural screen with 30% shading, inside these environments, there were benches with and without reflective material of the type Aluminet® with 50% shading. The plastic greenhouse presented lower temperature and relative air moisture, besides lower global solar radiation and photosynthetically active radiation. The benches with reflective material, independently of the environment, have promoted higher photosynthetic reflected radiation. Plants produced in the greenhouse had larger sizes, diameters, and leaves in their initial growth stage. As of 56 DAT, the plants in the agricultural screen presented greater heights and promoted greater pepper production. The reflective benches have favored the growth in diameter and at 14 and 28 DAT, and greater fruit production. It is concluded that the agricultural screen with 30% shading and reflective benches favor the Biquinho pepper fruit production.

Beans are one of the most important crops in Brazil but still have a low yield. The use of technologies such as the application of biostimulants can provide greater yield for the crop. Thus, the work aimed to evaluate the effect of using Azospirillum brasilense and phytohormones on Jalo Precoce beans. The experiment was carried out in randomized blocks with nine treatments and four replications. The treatments consisted of a control, Stimulate (compound of phytohormones), and A. brasilense applied isolated or associated to the seeds or in a furrow. The plant height, stem diameter, shoot dry matter, number of pods per plant, number of grains per pod, the weight of grains per pod, and 100-grain weight were favored by A. brasilense and compound of phytohormones. The highest yield of Jalo Precoce beans (2218 kg ha-1) was obtained using the A. brasilense + phytohormone compound applied in the sowing furrow. The grain yield of Jalo Precoce beans showed a high positive correlation with the number of pods per plant and medium correlation with stem diameter and shoot dry matter.

Brazil stands out among the world's largest soy producers. The uniformity in the deposition of seeds and the correct distribution of plants are important factors for the crop to express its maximum productive potential. The present study aimed to evaluate the influence of the lubricant agent “graphite”, applied during and after the chemical treatment of soybean seeds in function of its longitudinal distribution at different operating speeds. For this purpose, a seeder with mechanical type feeder was used, at three working speeds: 4, 6 and 8 km h-1 and conducted in a strip design, organized in a 2x3 factorial scheme, with two different modes of application of graphite and 3 operating speeds. The results presented showed that the addition of graphite concomitantly with the seed treatment, increases the unevenness of sowing, the same occurs in relation to the increase in the speed of operation. Graphite loses lubricating action when added to the seed treatment, increasing the number of failures. 

The fruits of Hymenaea stigonocarpa have a sweet, starchy fibrous structure used as food among wild animals and man in the field. In the present study, the physical, physicochemical, optical, microstructural, and antibacterial properties of aryl (H. stigonocarpa) film were investigated. The amylaceous solution was obtained from the aryl of H. stigonocarpa, the biodegradable film was prepared according to the casting technique. The physicochemical characteristics for thickness (mm), humidity (%), water solubility (%), biodegradability time, and transmittance (T%) were evaluated. Morphology by optical micrographic, and scanning electron, mathematical modeling in 3D, and for the mechanical parameters of tensile strength, maximum tension, elongation, and elasticity module, and biological properties on antibacterial activity (Staphylococcus aureus, Escherichia coli and Enterococcus faecalis). The results obtained for the biodegradable film were a brown-yellow color, aroma, and homogeneity, thickness 0.27 mm, humidity 12.45%, solubility in water 57.48%, the biodegradability of 100%, maximum and minimum transmittance 82.25, and 1.32 (T%), in the optical micrograph small imperfections were observed, and in the scanning electron micrograph small cracks. The mathematical modeling in 3D presented a surprising result, which is an important device in the aid of imaging. The mechanical characteristics for maximum tension 3.17 N, rupture stress 1.34 MPa, elongation 2.99% and elasticity with 90.07 MPa presented satisfactory results comparable to other biodegradable films of native starch. The bioactive film of the aryl (H. stigonocarpa) showed antibacterial activity against Staphylococcus aureus 7 mm, Escherichia coli 5 mm, and Enterococcus faecalis 8 mm. Biodegradable packaging from Hymenaea stigonocarpa aryl has great potential for use as a food packaging.

Brazil is the largest beans producer, and this legume is one of the primary sources of plant-based proteins. Some minerals, such asmanganese, are essential for this crop development. From the socio-economic importance of the beans crop, this study aims to evaluate theagronomic performance of irrigated common beans grown under different doses of manganese on two application periods. The experiment was conducted in the experimental area of the Instituto Federal Goiano, Campus Ceres (GO), adopting an experimental design arranged in a 2x4 factorial scheme with four replications, comprising two periods of application (V4 and R5 phenological stages) and four Mn doses (0, 150, 300, 450 g ha-1). The variables evaluated were plant height (m), number of pods per plant (NPP), number of grains per pod, 1000-grain weight (g), and yield (kg ha-1). The dose of 450 g ha-1 of Mn provided the highest yield regardless of the application period.  The higher NPP was obtained with the dose of 150 g ha-1 in V4. Also, the dose of 450 g ha-1 of Mn in V4 provided the most significant 1000-grain weight.

The application of magnetically treated water is a valuable technique for crop irrigation to enhance the yield and quality of agricultural products. This study aims to evaluate the effect of irrigation water depths and the application of water with and without magnetic treatment on the yield and quality of bell pepper fruits in a controlled environment, verifying the effect of magnetically treated water on soil water retention. Two experiments were conducted in the Irrigation Technical Center of the Universidade Estadual de Maringá, Maringá/PR; the first on Summer 2017-2018, and the second on Winter-Spring 2018. A randomized block design with a factorial scheme 3 x 2 with four repetitions was used for the first experiment and a 2 x 2 scheme with six repetitions for the second. The first factor was the water replacement levels (based on the crop evapotranspiration), and the second the irrigation water treatment, with or without magnetic treatment. The yield and number of fruits were determined after six and four harvests in the first and second experiments. Quality characteristics (soluble solids level, pH, and titratable acidity) were evaluated from three fruits of each plant. The data was submitted to the Tukey test (p ≤ 0.05). It was verified that the application of magnetically treated water did not influence yield. However, it increased the levels of soluble solids and pH. To evaluate the effect of applying magnetically treated water on soil retention, 12 pots filled with soil and without plants were used. An increase in the gravimetric soil moisture using magnetically treated water was perceived, demonstrating higher water retention when using the irrigation method.