ABSTRACT Thinning is a cultural practice that leads to balance between fruit yield and quality. It is carried out in a short period of time and requires qualified workforce, whose shortage ends up increasing costs. This study aimed at evaluating the thinning effect of metamitron on peach trees at different periods of time after bloom. The experiment was carried out in a commercial orchard of ‘Sensação’ peach trees located in Morro Redondo, Rio Grande do Sul (RS) state, Brazil, in 2015-2016 crops. Treatments were the application of 200 mg L-1 metamitron, 20, 30, 40, 50 and 60 days after full bloom (DAFB), and manual thinning 40 DAFB. Fruit abscission, effective fructification, period of manual and chemical thinning, number of fruits and yield per plant, mean fruit mass and fruit caliber were evaluated. When metamitron was applied 40 DAFB, percentages of fruit abscission and fruit set, besides the number of fruits, were similar to the ones found when manual thinning was carried out. The intensity of the thinning effect of metamitron in peach trees depends on the application period.

ABSTRACT Thinning is a cultural practice that leads to balance between fruit yield and quality. It is carried out in a short period of time and requires qualified workforce, whose shortage ends up increasing costs. This study aimed at evaluating the thinning effect of metamitron on peach trees at different periods of time after bloom. The experiment was carried out in a commercial orchard of ‘Sensação’ peach trees located in Morro Redondo, Rio Grande do Sul (RS) state, Brazil, in 2015-2016 crops. Treatments were the application of 200 mg L-1 metamitron, 20, 30, 40, 50 and 60 days after full bloom (DAFB), and manual thinning 40 DAFB. Fruit abscission, effective fructification, period of manual and chemical thinning, number of fruits and yield per plant, mean fruit mass and fruit caliber were evaluated. When metamitron was applied 40 DAFB, percentages of fruit abscission and fruit set, besides the number of fruits, were similar to the ones found when manual thinning was carried out. The intensity of the thinning effect of metamitron in peach trees depends on the application period.

ABSTRACT South American natural grasslands are composed of several species with different growth strategies, with variations in specific leaf area (SLA), leaf dry matter content (LDMC), specific root length (SRL) and specific root area (SRA). The objective of this study was characterizing in grasses cultivated with different levels of phosphorus (P) in the soil if species with higher leaf and root area production per unit of dry matter have higher tissue P concentration, P use efficiency and higher dry matter yield. The plant species were grown in a greenhouse in pots with 5 kg of soil in a completely randomized design with four replicates and two conditions of P availability: addition of 60 mg kg-1 soil and without addition of P. The species with the highest SRA had a higher leaf and root P concentration. The higher production of leaf or root surface area per unit of dry matter did not represent higher tissue P use efficiency. The group formed by species of genre Paspalum had a higher leaf and root P use efficiency, therefore, areas composed of this genre are preferred for P fertilization.

ABSTRACT South American natural grasslands are composed of several species with different growth strategies, with variations in specific leaf area (SLA), leaf dry matter content (LDMC), specific root length (SRL) and specific root area (SRA). The objective of this study was characterizing in grasses cultivated with different levels of phosphorus (P) in the soil if species with higher leaf and root area production per unit of dry matter have higher tissue P concentration, P use efficiency and higher dry matter yield. The plant species were grown in a greenhouse in pots with 5 kg of soil in a completely randomized design with four replicates and two conditions of P availability: addition of 60 mg kg-1 soil and without addition of P. The species with the highest SRA had a higher leaf and root P concentration. The higher production of leaf or root surface area per unit of dry matter did not represent higher tissue P use efficiency. The group formed by species of genre Paspalum had a higher leaf and root P use efficiency, therefore, areas composed of this genre are preferred for P fertilization.

ABSTRACT Grafting technique has been presented as an alternative for Araucaria angustifolia propagation. However, vegetative rescuing mature trees and obtaining large numbers of propagules is difficult, because the use of branch grafts has not been indicated due to its plagiotropic and morphogenic characteristic, generally resulting in undesired growth of the graft. So we aimed to describe the unpublished fact occurred in four plants of A. angustifolia grafted with grafts from primary branches that resulted in conversion to trunk. Plant growth and morphology were evaluated ten years after grafting. We verified vertical growth and organization of trunk and persistent branches with defined whorls, same to plants grafted with trunk grafts. Field tests with grafted plants using grafts obtained from the four plants resulted in same development pattern, proving the permanent morphogenic change and opening new perspectives for araucaria vegetative rescue and grafting. We concluded that trunciform shoots can be obtained by A. angustifolia grafting with plagiotropic primary branches. Despite the morphological clarity of trunciform shoots on grafted plagiotropic primary branches, it has not yet been possible to identify the causes of this reversion.

ABSTRACT Grafting technique has been presented as an alternative for Araucaria angustifolia propagation. However, vegetative rescuing mature trees and obtaining large numbers of propagules is difficult, because the use of branch grafts has not been indicated due to its plagiotropic and morphogenic characteristic, generally resulting in undesired growth of the graft. So we aimed to describe the unpublished fact occurred in four plants of A. angustifolia grafted with grafts from primary branches that resulted in conversion to trunk. Plant growth and morphology were evaluated ten years after grafting. We verified vertical growth and organization of trunk and persistent branches with defined whorls, same to plants grafted with trunk grafts. Field tests with grafted plants using grafts obtained from the four plants resulted in same development pattern, proving the permanent morphogenic change and opening new perspectives for araucaria vegetative rescue and grafting. We concluded that trunciform shoots can be obtained by A. angustifolia grafting with plagiotropic primary branches. Despite the morphological clarity of trunciform shoots on grafted plagiotropic primary branches, it has not yet been possible to identify the causes of this reversion.

ABSTRACT Agriculture has caused numerous concerns regarding the preservation of natural resources. In this context, agroforestry systems are emerging as a more sustainable alternative. The present study aimed to evaluate growth characteristics, radiation use efficiency, biomass partition, and yield of soybean grown in two agroforestry systems and full sun. A field experiment was conducted in Southern Brazil during the 2014/2015 crop year, in which transmissivity of solar radiation, leaf area index, radiation use efficiency, and yield of soybean were evaluated. The solar radiation dynamics varied among the study factors, mainly due to the agroforestry arrangements. Shading influenced the leaf area index, radiation use efficiency, biomass partition, and soybean yield. Based on the soybean yield values generated in this study, the use of more spaced agroforestry arrangements and Peltophorum dubium forest species is recommended. However, because the yield values were below the expected levels, it is not yet possible to confirm the full potential of soybean crop in agroforestry systems. Thus, new studies should be conducted in order to generate alternatives that make soybean cultivation feasible in agroforestry systems, such as assessing the use of more spaced agroforestry arrangements, the insertion of the soybean crop in the initial years of cultivation of agroforestry, as well as reduce intraspecific competition by decreasing the plant population of the crop.

ABSTRACT Agriculture has caused numerous concerns regarding the preservation of natural resources. In this context, agroforestry systems are emerging as a more sustainable alternative. The present study aimed to evaluate growth characteristics, radiation use efficiency, biomass partition, and yield of soybean grown in two agroforestry systems and full sun. A field experiment was conducted in Southern Brazil during the 2014/2015 crop year, in which transmissivity of solar radiation, leaf area index, radiation use efficiency, and yield of soybean were evaluated. The solar radiation dynamics varied among the study factors, mainly due to the agroforestry arrangements. Shading influenced the leaf area index, radiation use efficiency, biomass partition, and soybean yield. Based on the soybean yield values generated in this study, the use of more spaced agroforestry arrangements and Peltophorum dubium forest species is recommended. However, because the yield values were below the expected levels, it is not yet possible to confirm the full potential of soybean crop in agroforestry systems. Thus, new studies should be conducted in order to generate alternatives that make soybean cultivation feasible in agroforestry systems, such as assessing the use of more spaced agroforestry arrangements, the insertion of the soybean crop in the initial years of cultivation of agroforestry, as well as reduce intraspecific competition by decreasing the plant population of the crop.

ABSTRACT Cerrado biome is responsible for part of Brazilian food production. However, due to inadequate soil management practices, large areas of crop and forage are degraded, leading to environmental and economic losses. A crop-livestock-forest system (CLFS) is a sustainable production strategy that integrates different cultivations. This objective of this study was to evaluate agronomic characteristics and maize (Zea mayz L.) yield when consorciated with Panicum maximum cv. Tamani, cultivated between rows of eucalypts clones. The statistical design used was randomized blocks, constituted by the following treatments: Maize + AEC 043; Maize + AEC 007; Maize + AEC 2111; and Maize + AEC 2034. The analyzed variables included: spikes length, number of rows, number of grains per row, number of grains per spike, and grain yield. Based on the obtained data, it is possible to conclude that trees did not affect maize yield in a CLFS. Considering that only 66% of the area was used for agriculture, maize yield was higher than when it is planted in total area.

ABSTRACT Cerrado biome is responsible for part of Brazilian food production. However, due to inadequate soil management practices, large areas of crop and forage are degraded, leading to environmental and economic losses. A crop-livestock-forest system (CLFS) is a sustainable production strategy that integrates different cultivations. This objective of this study was to evaluate agronomic characteristics and maize (Zea mayz L.) yield when consorciated with Panicum maximum cv. Tamani, cultivated between rows of eucalypts clones. The statistical design used was randomized blocks, constituted by the following treatments: Maize + AEC 043; Maize + AEC 007; Maize + AEC 2111; and Maize + AEC 2034. The analyzed variables included: spikes length, number of rows, number of grains per row, number of grains per spike, and grain yield. Based on the obtained data, it is possible to conclude that trees did not affect maize yield in a CLFS. Considering that only 66% of the area was used for agriculture, maize yield was higher than when it is planted in total area.

ABSTRACT Extraction of olive oil gives rise to large quantities of pomace and liquid effluents, since on average only 21% of the weight of the olive corresponds to oil, the remaining 79% consists of water, bark, pulp and stone. With the intention to make available new forms of use of this residue, this research was proposed, with aimed to optimize the extraction of phenolic compounds from olive pomace resulting from oil extraction using methanolic extracts. The analysis of phenolic compounds (TPC) and the evaluation of the antioxidant activity (AA) were performed by spectrophotometry, and the individual phenols were carried out by LC-ESI-qTOF-MS. The data were evaluated by the application of the response surface methodology (RSM). The condition that promoted the highest TPC in an extract was using 40% methanol, 70 °C and 180 minutes (extract 7). The highest AA was in the extract obtained with 40% methanol, 45 °C and 180 minutes (extract 5). The highest individual phenol sum (IPS) was in the extract with 80% methanol, 45 ºC and 180 minutes (extract 6). Therefore, it is possible to conclude that the RSM was an interesting tool to measure the best conditions for extraction of phenolic compounds from olive pomace.

ABSTRACT Extraction of olive oil gives rise to large quantities of pomace and liquid effluents, since on average only 21% of the weight of the olive corresponds to oil, the remaining 79% consists of water, bark, pulp and stone. With the intention to make available new forms of use of this residue, this research was proposed, with aimed to optimize the extraction of phenolic compounds from olive pomace resulting from oil extraction using methanolic extracts. The analysis of phenolic compounds (TPC) and the evaluation of the antioxidant activity (AA) were performed by spectrophotometry, and the individual phenols were carried out by LC-ESI-qTOF-MS. The data were evaluated by the application of the response surface methodology (RSM). The condition that promoted the highest TPC in an extract was using 40% methanol, 70 °C and 180 minutes (extract 7). The highest AA was in the extract obtained with 40% methanol, 45 °C and 180 minutes (extract 5). The highest individual phenol sum (IPS) was in the extract with 80% methanol, 45 ºC and 180 minutes (extract 6). Therefore, it is possible to conclude that the RSM was an interesting tool to measure the best conditions for extraction of phenolic compounds from olive pomace.