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Due to its importance for oil production in Brazil and worldwide, the 'Picual' olive trees deserves special attention of to its good climatic adaptation and high yield and stability in the oil produced. However, there is a need to generate more technical information to improve the propagation and production system for nursery plants. The use of slow-release fertilizer (SRF) affects the quality standard of the plants formed in the nursery. The purpose of this study was to evaluate the effect of doses (0, 1.5, 3.0, 6.0, and 12 g L−1) of the SRF, Osmocote® (NPK 14-14-14), on morphological, biochemical and nutritional parameters of 'Picual' olive plants. It was found that the average value of maximum technical efficiency dose (MTED) for several morphological variables (plant height, stem diameter, total plant dry weight and root volume) was 7.18 g L−1. Furthermore, an Osmocote® dose of 8.35 g L−1 resulted in optimal leaf number and area. For the carbohydrate concentration (sucrose, starch and Total Soluble Sugar) in leaves, the best average values were obtained at 4.51, 5.48 and 6.12 g L−1 of Osmocote®, respectively. Additionally, the best growth responses of plants may also be due to increased internal macronutrient concentration such as nitrogen (N), phosphorus (P) and potassium (K) after treatment with 7.87 g L−1 of Osmocote®. The use of SRF (Osmocote®) is a viable alternative in the production of 'Picual' plants, as it promotes good morphological characteristics, synthesis of photosynthetic products as well as satisfactory nutritional status and plant growth. [ABSTRACT FROM AUTHOR]

Question: What conditions drive trait divergence during community assembly through environmental filtering, and why are some communities more trait‐diverse than others? Methods: An individual‐based, stochastic, spatially explicit metacommunity simulation model produced data on species traits, spatially autocorrelated, nested, feedback‐generated environmental factors, and resulting community composition. I quantified environmentally driven alpha trait divergence using the correlation r(RE) to measure the relationship between Rao functional diversity and environmental factors. Environmentally driven beta trait divergence was assessed through the correlation r(VE), involving environmental factors and the squared residuals (V) of a second‐order polynomial regression of community‐weighted means on environmental factors (E). Permutation tests, assuming independence between traits and species composition, were used to establish the significance of r(RE) and r(VE). Additionally, the method was applied to grassland and soil data collected in plots across southern Brazil. Both simulated and real data were analysed at two spatial resolutions. Results: Significant r(VE) correlations were frequent with factor interactions incorporated in community assembly simulations, while r(VE) correlations mostly remained within expected Type I error range when factor interactions were absent. r(VE) was stronger than r(RE) at a finer spatial resolution and weaker than r(RE) when smaller community units were combined into larger units. r(VE) for specific leaf area (SLA) was related to soil variables, likely due to their interacting effects with total vegetation cover. When small plots were aggregated into larger units, r(VE) became non‐significant, while r(RE) increased. Conclusions: Environmentally driven trait divergence emerges during community assembly due to interactions between factors affecting the selection of individuals based on their traits. When the effects of these factors are spatially nested, including hidden, feedback‐generated ones, trait divergence arises at the beta or alpha dimension, depending on the scale of the community units. This suggests that plant‐to‐plant positive or negative interactions, which can feedback on environmental factors and generate heterogeneity, do not necessarily lead to trait divergence if these factors do not interact. [ABSTRACT FROM AUTHOR]

Butia spp. is a palm tree native to southern Brazil and Uruguay. The fruits are consumed fresh and used to make many food products, while the leaves are commonly used to make crafts. In January 2018, severe symptoms of wilt and drying were identified in clusters of Butia odorata occurring on the leaf and the rachis (in a proportion of 50% of leaf area). The pathogen was isolated from a stump extracted from a symptomatic tree. The morphologic characters showed a presence of macroconidia and microconidia with a classic salmon color of some species of the Fusarium genus. The molecular identification of the locus of actin (ACT), calmodulin (CAL), factor elongation 1-alpha (TEF1) and histone (HIS3), confirmed the identity of Fusarium anthophilum. This finding will help growers and agronomists prevent and manage this disease. To the best of our knowledge, this is the first report of Fusarium antophilum causing disease in Butia odorata. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Biological invasions are a major environmental challenge today. Interactions between invasive and native species can significantly shape community structures, influencing coexistence, diversity and functional composition of species. The subtropical Atlantic Forest in southern Brazil, a recognized biodiversity hotspot, provides a unique setting to study these interactions, given its vulnerability to alien tree invasions.Our study sought to elucidate the impacts of such invasions on this fragile ecosystem by addressing key questions: (1) How are tree community diversity patterns affected by the abundance of invading alien tree species? (2) What are the patterns of coexistence between native and alien invasive trees? (3) Is the functional composition of the forests altered by the abundance of invasive trees?To address these questions, we compiled data on the abundance and functional traits of native and invasive trees. We determined the diversity patterns and functional composition of plots with different degrees of invasion. These data were analysed using generalized linear mixed models, principal component analysis and a coexistence index.In plots with a higher abundance of invasive trees, there was a significant decrease in the taxonomic and functional richness (FRic) of native species. Furthermore, we observed that invasive alien trees coexisted with native species, and as the abundance of invasive trees increased, the native community‐weighted mean of the leaf area (LA) and specific leaf area (SLA) decreased.In conclusion, within the subtropical Atlantic Forest areas of southern Brazil, our findings highlight that the abundance of invasive trees adversely affects the taxonomic and FRic of native species. Furthermore, while invasive alien trees were found to coexist with native species, increased invasive abundance corresponded to a reduction in the LA and the SLA of the native community. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fire is an ecological factor that strongly influences plant communities and functional traits. Communities respond differently to fire, either decreasing or increasing in flammability and resource acquisition strategies. This study aimed to investigate the influence of fire over traits associated with flammability and the plant economic spectrum in a stressful and infertile mountainous grassland located in the Espinhaço mountain range in Brazil. Non-graminoid plant species were sampled in 60 5 m × 5 m plots distributed in three fire frequency categories. We measured several traits related to flammability—leaf dry matter content (LDMC), twig dry matter content, leaf area, bark thickness, branching architecture, plant height, leaf toughness (LT), and specific leaf area (SLA). Traits responded differently to the increase in fire frequency. For instance, the LDMC and LT were lower while the SLA was higher at high fire frequencies, indicating a trend towards reduced heat release and fire residence time. This shift resulted in the dominance of plants with a relatively more acquisitive strategy. This study brings evidence that traits respond coordinately towards a reduction of flammability with the increase in fire frequency and are strong indicators of the filtering role that fire plays as a disturbance on rupestrian grassland vegetation. [ABSTRACT FROM AUTHOR]

Understanding trait variation along environmental gradients is crucial for assessing the adaptive potential of species. We analysed the intraspecific variation in six morphological traits of Frullania ericoides across environmental gradients (elevation, canopy openness and distance to water sources) in a humid ecological refuge in Brazil's semi-arid region. The traits measured (mean and coefficient of variation) were: leaf lobe area, leaf lobule area, underleaf area, stem width, ratio between leaf lobule area and leaf lobe area, and ratio between the number of laminate lobules and the total number of lobules. Seventy specimens from eleven localities (populations) showed greater intrapopulation than interpopulation mean trait variation. All traits, except for the ratio between leaf lobule area and leaf lobe area, presented interpopulation differences. Two trait strategies emerged: one related to water storage and plant size, and the other linked to proportional increases in leaf lobule area and lobe area. The lower the elevation was, the higher were the mean values of leaf lobe area and leaf lobule area, and the variance of stem width. The species exhibited significant trait variation, which can be decisive in the responses of populations to new selective pressures of establishment and maintenance. [ABSTRACT FROM AUTHOR]

The height, diameter, and leaf area of trees influence the anatomical structures because rapid growth requires maintenance of the water conduction in sapwood, despite environmental variations that may limit water supply. Our objective was to evaluate the influence of water availability conditions on the soil in humid and dry sites, on the percentage of sapwood along the trunk, and on the hydraulic properties of the wood of eucalyptus clones. The experimental plantings were carried out in Brazil in humid and dry sites. Six-year-old E. urophylla and E. grandis × E. camaldulensis clones were evaluated under 100% water (W) at each site considering local precipitation and 33% rainfall exclusion (WE) conditions. The wood was evaluated for heartwood and sapwood percentage, apparent sapwood density, diameter, wall thickness and vessel area, potential hydraulic conductivity, and Huber value. Rainfall exclusion at the dry site promoted an increase of 9% of sapwood when compared to the humid site, with an impact on diameter, area, wall thickness and vessel composition index, and lower Huber value for E. grandis × E. camaldulensis wood. The rainfall exclusion increased the sapwood percentage and reduced the growth of E. urophylla. E. grandis × E. camaldulensis had a higher sapwood apparent density at the dry site, while E. urophylla had a higher density at the humid site. The genetic diversity of the clones was expressed in the tree growth and in the sapwood content and was modified by humid and dry sites, which demonstrates different rusticity levels of the clones. [ABSTRACT FROM AUTHOR]

Coffee is an agricultural commodity with global commercial importance capable of impacting the production chain. The quantification of defoliation at harvest is important for monitoring crop yield because defoliation is one of the main types of damage caused by this agricultural operation in coffee crops. Thus, the objective of this study was to evaluate the relationship between yield and defoliation obtained in the field and obtained through remotely piloted aircraft (RPA) images. The experiment was conducted in a coffee plantation belonging to the Federal University of Lavras (UFLA), Lavras, Minas Gerais state, Brazil. An RPA with a rotary wing containing a multispectral camera was used in autonomous flight mode with a height of 30 m, an image overlap of 80%, and a speed of 3 m s-1. The images were collected before and after the 2020 and 2021 harvest, defoliation data obtained in the field were measured in 2020 and 2021, and the yield was measured from 2019 to 2021. Image processing was performed in the software PhotoScan, postimage processing was performed in QGIS, and statistical analyses were performed using the software R. With the processing of the images in 2020, the crop showed reductions of 17.3% and 18.4% in leaf area and volume, respectively, after harvest. In 2021, the crop showed reductions of 12.8% and 9.8% in leaf area and volume, respectively, after harvest. The leaf area and leaf volume of the coffee plantation after harvest could be quantified by means of images obtained by RPA, which allowed the observation of the loss of area and volume of the coffee plantation. Furthermore, it was possible to analyse the interactions between field data and the yield of the same harvest year, which were directly proportional, and the interaction of image data from one year with the previous yield, which were inversely proportional. In the year 2020, there was a reduction of 17.3% in leaf area after harvest, and a reduction of 18.4% in leaf volume after harvest in the plots under study. In the processing carried out in 2021, there was a 12.8% reduction in leaf area after harvest, and a 9.8% decrease in leaf volume after harvest in the plots under study. [ABSTRACT FROM AUTHOR]

Copyright of Biotropica is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Pecan farming is a long-term investment which needs quality seedlings to establish an orchard. Pecan rootstocks must have a vigorous radicular system to form quality seedlings. Liquid humus, which acts as an agent that promotes their growth and development, is a bioinput that is specially used in organic production systems. This study aimed at evaluating effects of different frequencies of liquid humus application on pecan rootstock growth and development in an organic system. Liquid humus at 30% was applied every 7, 14, 21 and 28 days. The control treatment consisted of water application. The experiment was carried out with 'Barton' rootstocks in a greenhouse at the Embrapa Clima Temperado located in Pelotas, RS, Brazil. The following variables were evaluated 280 and 480 days after transplantation: plant height; stem diameter; leaf area; fresh and dry masses of the aerial part; main and secondary root lengths; fresh and dry masses of roots; fresh and dry masses of the main root; fresh and dry masses of secondary roots; and the Dickson Quality Index. Liquid humus increased secondary root length of pecan rootstocks, mainly when it was applied every seven days. Thus, the bioinput may be used for this purpose. [ABSTRACT FROM AUTHOR]

Bell pepper is one of the vegetables that most contributes to the horticultural economy of the state of Para, Brazil, although the state has a low production of this vegetable. The objective of this study was to evaluate the adaptability of bell pepper (Capsicum annuum L.) cultivars grown in protected cultivation under the edaphoclimatic conditions of southeastern state of Para. The experiment was conducted at the Federal Rural University of Amazonia. A randomized block experimental design was used, with four replications. The treatments consisted of 9 bell pepper cultivars: Itapua 501, Yolo Wonder, Chapeu de Bispo Cambuci, Proveito, Amarelo SF 134, Rubi Gigante, Amarelo Alegria, All Big, and Amarelo Satrapo Sais. The parameters analyzed were: plant height (cm); number of fruits per plant; fruit weight (g); transversal (mm) and longitudinal diameters of fruits (mm); leaf area (cm²), width (cm), length (cm), perimeter (cm), and ratio (cm); and chlorophyll a, chlorophyll b, and total chlorophyll. The cultivar Amarelo Satrapo showed greater adaptability to cultivation in the studied region, presenting higher fruit weight, yield, and transversal diameter, leaf area and length, and good morphophysiological development. The cultivars Itapua 501, Amarelo SF 134, and Rubi Gigante showed good performances for morphophysiological parameters. The cultivars that presented the highest chlorophyll indices were Proveito, Itapua 501, All Big, and Amarelo Satrapo. The cultivar Amarelo Satrapo presented the highest adaptation to the climate conditions of southeastern Para. [ABSTRACT FROM AUTHOR]

Greenhouse experiments were carried out aiming to characterize—morphologically and biochemically—resistant and susceptible plants of C. sumatrensis. Two experiments were carried out to evaluate the behavior of morphological variables such as leaf area, height, and dry biomass weight, without application of paraquat (1,1'-dimethyl-4,4'-bipyridinium dichloride). Other experiments were conducted with two rates of paraquat application (0 and 800 g a.i ha−1); physiological variables were assessed at 2, 4, and 24 h after application (HAA), and plants were collected at 4 HAA for biochemical analyses of antioxidant enzymes and cell membrane peroxidation level. Without herbicide application, paraquat-resistant populations had higher dry biomass, leaf area, liquid photosynthetic rate, carboxylation efficiency, and stomatal conductance. The recovery of the photosynthetic apparatus by resistant plants after paraquat application is rapid (16 HAA) and, in general, presents physiological improvements in terms of photosynthetic rate and carboxylation efficiency. After paraquat treatment, the antioxidant system enzymes of resistant plants showed increased activity and decreased membrane peroxidation, indicating that these enzymes play an important role in the resistance mechanism of these plants. [ABSTRACT FROM AUTHOR]

The phyllochron is an indispensable parameter associated with the potential production of sorghum. Accordingly, management practices applied directly in the sorghum (Sorghum bicolor (L.) Moench) crop, such as the cutting technique, provide the ability of plants to regrowth and reestablish the performance of vegetative and reproductive development based on the stimulation of growth in the photosynthetically active area. Appropriately, the aim of this study was to evaluate the alterations in phyllochron and leaf emission rate expressed by the implementation of cutting management practices in sorghum plants from high and low-quality seeds. The study was performed in the experimental and didactic area of the Federal Institute of Rio Grande do Sul (IFRS) - Ibirubá, Rio Grande do Sul, Brazil. The experimental design was completely randomized and the treatments were plants from higher (HQS) and lower (LQS) quality seeds and two season crops (2015/16 and 2016/17) with eight replications. The mean phyllochron (°C day leaf-1), height (cm), main stem diameter (cm), number of nodes, dry mass (kg ha-1), and number of tillers were evaluated as a strategy to verify the performance of each treatment. Furthermore, meteorological data obtained from an automatic station was required to calculate phyllochron and the evapotranspiration (ETc). Finally, this study indicated that the diameter of the stem and tillers is directly associated to the accumulation of a dry mass of the crop, based on the results of biomass productivity. Moreover, it was demonstrated that forage sorghum plants derived from HQS indicated a higher capacity to accumulate photoassimilates, stimulating the production of dry mass. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the efficiency of organic compost produced through composting in the development of Moringa oleifera seedlings. The experiment was carried out in a greenhouse in Feira de Santana-BA, Brazil. The design was randomized blocks (RBD), with seven treatments per block and four replicates. The following treatments were tested: commercial substrate; sand (S); S/organic compost (OC) 80/20; S/OC 60/40; S/OC 40/60; S/OC 20/80; S/OC 0/100. The organic compost was formed by pruning residues and vegetable remains that were not cooked. The addition of organic compost promoted the highest means for the parameters height, number of leaves, height/collar diameter ratio, root dry mass and shoot dry mass. For leaf area, height/shoot dry mass ratio and collar diameter, the proportions of the compost had no influence. Higher means of parameters such as tuberous root length and diameter and tuberous structure dry mass were observed in the commercial substrate, which may indicate stress in seedlings of this treatment. Substrates with a lower proportion of organic compost are more suitable for the production of M. oleifera seedlings. [ABSTRACT FROM AUTHOR]

Nitrogen (N) is the element supplied by the soil that limits the development of irrigated rice. The hypothesis of the present is that to meet higher demand for N by the plant due to the higher potential yield, it is not necessary to apply a higher dose of N fertilizer. This studyevaluated the efficiency of N utilization, the rate of growth and accumulations of N by plants and the grain yield of two rice cultivars, short cycle and medium cycle, with and without N fertilization. A field experiment was installed in the Rio Grande do Sul, southern Brazil. The treatment factors evaluated were cultivar, with medium and short cycles, with doses of 0 and 150 kg N ha-1. Growth curves, absorption rate, N content and leaf area index over time, root area and grain yield were analyzed. The medium cycle cultivar has a greater potential to explore the environment when compared to the short cycle rice cultivar, both for greater leaf area and root area per cultivation area, as well as for longer exploration times. Thus, the medium cycle cultivar has greater N utilization efficiency and higher grain yield. [ABSTRACT FROM AUTHOR]

Late sowings anticipate flowering and decrease the soybean vegetative plasticity. These changes may limit the ability of plants to tolerate leaf area losses. The objective of this research was to evaluate the sowing date effect on soybean tolerance to defoliation at the beginning of pod formation. The experiment was set in Lages (Santa Catarina State, Brazil) during the 2016/2017 growing season. Two sowing dates were tested: November 2, 2016 (preferential) and December 15, 2016 (late). Five levels of defoliation (0%, 17%, 33%, 50% and 67%) of cultivar NA 5909 RG were imposed at the R3 growth stage. Grain yield showed a quadratic response to defoliation, ranging from 4,313 to 6,478 kg ha-1 in the preferential sowing date and from 3,374 to 4,443 kg ha-1 in the late sowing date. The plants tolerated up to 45.6% of defoliation in early sowing and 55.8% in late sowing, without yield losses, in comparison to the control. The highest level of defoliation reduced grain yield by 26.9% and 13.4% in early and late sowings, respectively, compared to the control. The delay of sowing date did not increase the sensitivity of cultivar NA 5909 RG to defoliation at the beginning of pod formation. [ABSTRACT FROM AUTHOR]

Brazil is the largest Coffea arabica L. producer and exporter in the world market. In view of the need for nitrogen fertilization, the objective of this work was to evaluate the use of digital images of coffee leaves as a function of nitrogen concentration and cultivars, as well as to evaluate the most adequate sampling of this technique to predict leaf nitrogen. The experiment was set in a greenhouse, at UNESP - Experimental Campus of Registro-SP, using 12L pots with medium sand. A completely randomized design was adopted, in a 4 x 2 factorial scheme, with four concentrations of N (0, 50, 100 and 200 mg dm-3), and two coffee cultivars (Mundo Novo and Obatã), with ten replications. The variables evaluated were: hue, dark green color index (DGCI), leaf area and leaf nitrogen content. The hue and DGCI were influenced by N concentration, cultivar and are dependent on the day after treatment application and the number of leaves used. The use of five leaves per replication was more adequate to estimate leaf N content. Hue, DGCI and leaf area were higher in Obatã depending on the day after application of the treatment and N concentration. [ABSTRACT FROM AUTHOR]

Mini-cutting is the most common commercially used clonal propagation method in Brazil. However, several environmental interferences can impact this process, hindering the production of propagules. Mini-tunnel have been used to overcome these difficulties, allowing for an increase in the productivity of mini-stumps and the rooting of mini-cuttings. This study aimed to evaluate the effect of minitunnel models on the mini-stump productivity of two hybrid eucalyptus clones over two seasons. The study was conducted in the seedling nursery of a forestry company located in Alto Vale do Jequitinhonha, Minas Gerais, Brazil. Three models of the mini-tunnel were used: mini-tunnel 35 cm, 55 cm, 55 cm tubular, and without cover (control) over two seasons (cold and hot). The total and effective productivity of mini-cuttings were evaluated and the levels of chlorophyll A and B, total chlorophyll, height, leaf area, and dry matter of the mini-cuttings were determined. Together, season and use of the mini-tunnel influenced the productivity of the minicuttings of both clones. Use of the mini-tunnel resulted in high productivity, especially in the cold period. Mini-cuttings produced during the hot season showed greater growth, dry matter, and leaf area than those collected during the cold season. The use of minitunnels is an effective method to increase the productivity of clonal eucalyptus mini-gardens, as shown here by its overall positive influence on mini-cuttings of both genotypes. [ABSTRACT FROM AUTHOR]

Austropuccinia psidii, the causal agent of myrtle rust, was, for many years, restricted to the Americas, but since reaching Hawaii in 2005, the pathogen has expanded its global range exponentially. In Brazil, myrtle rust is the main fungal disease in guava plants. Despite this, there are few studies on guava rust epidemiology. The objectives of this study were to quantify the monocyclic components of rust and to evaluate the photosynthetic damage caused by A. psidii in young and old leaves of 'Paluma' guava. The monocyclic components of guava rust and gas exchange in healthy or inoculated (lO3 ml- urediniospores of A psidii) leaves were quantified over time. Additionally, young leaves were inoculated with varying concentrations of A. psidii inoculum, and leaf gas exchange and chlorophyll fluorescence were measured at 25 days postinoculation. The relationship between the relative C02 0assimilation of a diseased leaf (Px) and a healthy leaf (Pa) is related to disease severity (x) by PJPa = (1 - x). The density of lesions, disease severity, and urediniospore production were high in young leaves, averaging 58 lesions cm, 50% leaf area diseased, and 2.5 x 104 urediniospores per lesion, respectively. Rust symptoms were not observed in old leaves, and resistance to infection did not cause any photosynthetic cost to these leaves. On young leaves, 3 was 2.13, indicating a reduction on C02 assimilation at green tissues from symptomatic leaves. Our data revealed that photosynthesis reduction in diseased guava leaves was caused by biochemical and photochemical damage rather than by stomatal limitation. [ABSTRACT FROM AUTHOR]

Planting a peach orchard is highly expensive and may be influenced by variables such as attack by pathogens and diseases. Cultivar is one of the most important items within the production system and it is one of the few that may be modified without changes in costs. Current research evaluates the adaptability of peach cultivars 'Chimarrita', 'Eragil', 'Charme', 'Ouro', 'Seleção 01/08', 'FLA 8-1' and 'Della Nona' in the region of Campos Gerais PR Brazil. Experiment was conducted by randomized blocks, with seven treatments (cultivars) and eight replications. Variables analyzed comprised specific leaf area (cm² g-1), stalk diameter (mm), length of main stem (cm), volume of canopy (m³), incidence and severity of rust and early fruit, and percentage of attack by Grapholita molesta (Busck) (%). Cultivars Chimarrita and Ouro were more susceptible to the attack of grapholite (95.5% and 98%, respectively) and rust, with AACPS of 14.65 for Chimarrita and 15.67 for Ouro. Cultivars Charme, Seleção 01/08 and Eragil were more adapted for Campos Gerais, had little effect on growth variables such as the length of main stem, specific leaf area, stalk diameter and volume of canopy, even with the occurrence of diseases and pests which affect the culture. [ABSTRACT FROM AUTHOR]

Copyright of Revista Caatinga is the property of Revista Caatinga and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Soybean tolerance to defoliation may be affected by population density, as the plant population interferes with the crop leaf area index . This study aimed to evaluate the effect of defoliation at the beginning of pod formation on the agronomic performance of soybean at different plant densities. The experiment was conducted under field conditions in Campos Novos, SC, Brazil, during 2016/2017 and 2017/2018 growing season. The experimental design was a randomized block in a split-plot arrangement. The main plot consisted of three densities (100,000, 300,000, and 500,000 plants ha-1), whereas the subplots consisted of the cultivar NA 5909 RG submitted to five defoliation levels (0, 16.6, 33.3, 50, and 66.6%). Grain yield ranged from 4,219 to 5,356 kg ha-1 in the 2016/2017 growing season and 3,732 to 5,186 kg ha-1 in the 2017/2018 growing season. Plant density did not interfere with the grain yield response to defoliation performed at the beginning of pod formation. The 16.6% defoliation increase grain yield by 7.5 and 5.6% relative to the control in 2016/ 2017 and 2017/2018 growing seasons, respectively. The soybean tolerate defoliation of up to 33.3% at R3 with no significant decrease in grain yield, regardless of the plant density. [ABSTRACT FROM AUTHOR]

The rupture of Fundão dam was the biggest environmental disaster of the worlds' mining industry, dumping tons of iron ore tailings into the environment. Studies have shown that the Fundão dam's tailings are poor in nutrients and have high Fe and Mn concentration. In this context, our objective was to evaluate the growth performance of two native tree species (Bowdichia virgilioides and Dictyoloma vandellianum) in two treatments: fertilized soil and fertilized tailings. We hypothesize that the high concentrations of iron and manganese in the tailings can impair the growth performance of plants by interfering with the absorption of nutrients made available through fertilization. Soil and tailings samples were collected in the municipality of Barra Longa (MG, Brazil), and then fertilized with mixed mineral fertilizer ("Osmocote Plus 15–9-12" at 7.5 g L−1). The experiment was conducted for 75 days in a greenhouse using 180 cm3 tubes. We evaluate chlorophyll content, maximal PSII quantum yield, root length, shoot length, root:shoot ratio, leaf area, specific leaf area and leaf area ratio, dry mass, macro- and micronutrients concentration in the tissues, and metal translocation factor. Although assuring the adequate levels of the main nutrients to plant growth (N, P, K, Ca, and Mg), the fertilization did not reverse the negative effect of tailing on these species. The high concentration of Fe in the tissues associated with less biomass production, lower plant height, smaller leaf area, bigger specific leaf area, and reduced chlorophyll content indicates a probable phytotoxic effect of iron present in the tailings for D. vandellianum. Our results base further field evaluations and longer experiments, which will facilitate the understanding of the performance of tree species submitted to tailings with fertilization. So far, this study suggests that B. virgilioides are more tolerant to excess Fe from the tailings of Fundão dam than D. vandellianum. [ABSTRACT FROM AUTHOR]

Papaya is among the main fruit species produced in Brazil, representing high socioeconomic importance in productive regions. Changes in production methodologies aim to meet market demands and sector sustainability. In this sense, the use of organic compounds has been successfully used in the production of seedlings. The objective of the study was to evaluate the potential use of different sources of organic material for the composition of substrates used in the production of papaya seedlings, identifying the effects on the emergence and development of plants. Therefore, the treatments were composed of different substrates, namely: T1 - Soil; T2 - 75% soil and 25% chicken litter; T3 - 75% soil and 25% earthworm humus; T4 - 75% soil and 25% tanned cattle manure. When evaluating the characteristics, it was found that substrates composed of the fractions of earthworm humus and cattle manure allowed increases in the characteristics of shoot length, number of leaves, leaf area and stem circumference, while the presence of chicken litter interfered negatively on all the variables studied. It was concluded that organic compounds have the potential to favor the production of papaya seedlings. In this sense, the composition of the substrate alters the emergence and development of papaya seedlings, and the use of a fraction of 25% of earthworm humus allows the formation of seedlings with greater vigor, while the use of chicken litter in this same proportion should be avoided. [ABSTRACT FROM AUTHOR]

A culture is an activity that stands out in the semi-arid region of the Northeast of Brazil for the management of entrepreneurship and income. However, in this region, agricultural production has been affected by excess salts in water and soil. Therefore, the search for strategies that reduce the problems caused by salinity in cashew cultivation is of great importance, with organic fertilization being a promising alternative. Therefore, the objective of this work was to evaluate the growth of the precocious dwarf cashew tree 'BRS 226 Planalto' under irrigation with saline water and fertilization with cattle manure. The experiment was carried out in drainage lysimeters, in a greenhouse. The experimental design used was a randomized block design, in a 5 × 4 factorial scheme with three replications, with five levels of electrical conductivity of the irrigation water (0.7; 1.4; 2.1; 2.8 and 3.5 dS m-1) and four fertilization rates with cattle manure (2.5, 3.5, 4.5 and 5.5% based on soil volume). The growth of precocious dwarf cashew was measured by the diameter of the stem of the rootstock and of the scion, the plant height, the leaf area and the number of leaves, at the 122 days after transplantation. The salinity of irrigation water from 0.7 dS m-1 inhibited the initial growth of the precocious dwarf cashew tree 'BRS 226 Planalto', at 122 days after transplanting. Fertilization with high doses of cattle manure reduced the growth variables of the precocious dwarf cashew tree 'BRS 226 Planalto'. [ABSTRACT FROM AUTHOR]

Although cabbage is one of the most important vegetables in Brazil, seedling production is carried out empirically by producers, given that there are no literature reports on the optimal start time and management strategy for seedling fertigation. The present study aimed to assess the influence of fertigation management on the development of cabbage seedlings, in order to determine the best start time and application intervals for nutrient supply. The study consisted of two experiments conducted in a randomized block design, with six repetitions each. The first involved six fertigation start times (0, 3, 6, 9, 12 and 15 days after emergence) and the second consisted of five treatments, that is, five fertigation application frequencies (every 3, 4, 5, 6 and 7 days after the first application). Biometric, physiological and nutrient characteristics were assessed when the seedlings reached the ideal (commercial) transplanting stage. Fertigation start times had a significant effect on the number of leaves, shoot and root dry weight, leaf area and macronutrient accumulation. The best results were obtained for a start time of 0 to 6 days after emergence (DAE). Application intervals had a significant effect only on calcium and sulfur accumulation. It was concluded that cabbage seedling fertigation should start three days after emergence, adopting a four-day application interval. [ABSTRACT FROM AUTHOR]

This study investigated the foliar plasticity in Schwartzia brasiliensis in restinga formations (shrub and shrub-tree restinga) in southern Brazil. In each area, 10 individuals were selected and leaves in sunlight were collected for an analysis of functional leaf traits, including: fresh and dry leaf mass, leaf area, specific leaf area, succulence, stem diameter, plant height and tissue thickness. Environmental variables were measured considering soil mineral nutrition, water availability and photosynthetically active radiation. Phenotypic plasticity index was calculated for studied attribute. We compared means with a Student's t-test and the weight of environmental variables with a PCA. Results showed that the main leaf traits that differentiated the populations were leaf dry mass, specific leaf area, lamina thickness and plant height, while the main predictor environmental variables were gravimetric humidity, solar radiation, soil CEC, phosphorus content and salinity. In the shrub restinga, there is greater investment in mechanical support as a water saving strategy due to greater exposure to solar radiation. In the shrub-tree restinga, there is greater investment in photosynthetic production, since the shade provided by the treetops of other species attenuates the radiation effect. Despite the low plastic potential, the populations present structural adjustments that respond to the environmental heterogeneity. [ABSTRACT FROM AUTHOR]

Optimization in the use of inputs in the production of seedlings of Corymbia citriodora and Eucalyptus dunnii. Corymbia citriodora and Eucalyptus dunnii are species of relevant importance due to the quality of the wood and growth potential in Southern Brazil. Therefore, we aimed to identify containers and doses of controlledrelease fertilizer capable of enhancing the morphophysiological quality and growth of these species in the nursery, aiming for the proper management of these inputs. The seedlings were produced in two volumes of containers (50 e 110 cm³), filled with Sphagnum peat-based substrate, mixed with different doses of controlledrelease fertilizer (CRF) NPK 15-09-12 (0, 3, 6, 9 e 12 g L-1 of substrates). In addition, the morphological (height, stem diameter, leaf area, dry weight of shoot, root, and total) and physiological (chlorophyll a and b index and quantum yield of the photosystem II) attributes were evaluated. The morphological attributes proved to be suitable indicators of the quality of C. citriodora and E. dunnii seedlings, allowing to recommend the container of 50 cm³ and the doses of 9.0 g L-1 of controlled-release fertilizer for both species. At the same time, the physiological variables evaluated were not responsive to the effect of the treatments. [ABSTRACT FROM AUTHOR]

Experiments were conducted to examine the effect of time of planting on the performance of 'Albion' and 'Camarosa' strawberry plants in a greenhouse in Brazil. New transplants were planted in March, April, May or June in the first year, and in March, April or May in the second year. Information was collected on crown production, leaf area expansion, shoot dry weight, marketable yield and average fruit fresh weight. Vegetative growth and marketable yields were higher in 'Camarosa' than in 'Albion', while the reverse was true for average fruit fresh weight. The number of crowns/plant, leaf area/plant and shoot dry weight generally decreased as planting was delayed. Yields were highly variable with no clear pattern across years, except for lower yields with the plantings in June. Mean yields (± SE) were 766 ± 72 g/plant for March, 876 ± 135 g/plant for April, 723 ± 169 g/plant for May and 533 ± 209 g/plant for June. Average fruit fresh weight decreased as yield increased and was lower in the earlier plantings. The results of these experiments suggest that the new transplants can be planted from March to May for commercial production in this area. [ABSTRACT FROM AUTHOR]

Plants adapted to different habitats exhibit differences in functional traits and these characteristics are influenced by soil properties. We tested the hypothesis that soil resource availability influences the functional traits of plants, affecting therefore herbivory levels. We examined three Byrsonima plant species with different life forms that occurred across a distinct edaphic habitat along the Doce River Basin, South-eastern Brazil. We characterized habitats according to soil nutrient concentration and measured functional characteristics of crown architecture, leaf nutrients, sclerophylly, leaf area and leaf density. In addition, we evaluated how these variables influenced herbivory levels of congeneric plants. Our data show that species along a gradient of soil nutrients have functional characteristics influenced by habitat, which in turn affect herbivory levels. By comparing congeners with different life forms found along a stress-gradient of continuous habitats, we describe a corresponding gradient of plant functional traits and tissue consumption by herbivorous insects. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Basil is a medicinal and spice plant widely used in the Northeast region of Brazil. However, its production can be affected by the soil salinity and water used for irrigation. For the development of plants in saline conditions to occur, it is necessary that their nutritional status is adequate. Thus, the objective was to evaluate the effect of nitrogen fertilization on growth and gas exchange of purple basil submitted to salinity. The experiment was performed at the Federal University of Paraíba, adopting a randomized block design in an incomplete 5 x 5 factorial scheme, with five electrical conductivities (ECw = 0.0, 0.81, 2.75, 4.69 and 5.50 dS m−1) and five doses of nitrogen (N = 0.00, 58.58, 200.00, 341.42 and 400.00 mg L−1), generated through the central composite design. Plant height, number of leaves, stem diameter, leaf area and root length were evaluated at 45 days. Stomatal conductance, net CO2 assimilation rate, transpiration, water use efficiency, intrinsic water use efficiency, intrinsic efficiency of carboxylation and leaf temperature were evaluated. The data were analyzed through analysis of variance and regression. Foliar N fertilization attenuated the harmful effect of salt stress, increasing stem diameter, net CO2 assimilation rate, intrinsic efficiency of carboxylation and leaf temperature. Salinity reduced the growth of basil plants as the ECw rised. Gas exchange was stimulated by salinity and reduced by the foliar N fertilization. The number of leaves and leaf area increased with nitrogen fertilization. [ABSTRACT FROM AUTHOR]

There is currently a lack of information regarding the performance of cover crops grown in the Coastal Tablelands region in the North of the Brazilian state of Espírito Santo, where zero tillage is increasingly being adopted. The objective of this study was to evaluate the agronomic performance of six cover crops (ruzi grass, jack bean, and the millets ADR 300, ADR 500, ADRf 6010, and BRS 1501) under two irrigation regimes. A field experiment setup was based on randomized blocks with split plots and four repetitions. Shoot dry matter content, plant height, leaf area, chlorophyll fluorescence, and root growth of the cover crops were evaluated. The irrigation regime influences the agronomic performance of most of the cover crops, with the exception of jack bean and ADRf 6010 millet, which were tolerant to water deficiency, based on our evaluations of the variables shoot dry matter, plant height, and leaf area. In terms of biomass production, ADRf 6010 millet is the most suitable crop for use in conservation systems under conditions of water stress in this region. [ABSTRACT FROM AUTHOR]

Many issues involving leaf areas (LA) allometry, such as the possibility of adjusting morphometric models based on the leaves of different species and the influence model performance on intraspecific variability, are still unclear. In this work, we described allometric equations for 14 different woody tropical species. This study's novelty is to show how a generalised allometric equation accurately estimates LAs of different species with similar leaf morphologies [oblong: Ŷ = 0.6356(LW)1.0260, and elliptical: Ŷ = 0.6552(LW)1.0094]. Natural variation that occurs in the leaf development does not represent an obstacle to the implementation of generalised models. In general, simple linear models are considered ineffective to describe the full range of leaf variation. Extrapolation of these equations to other woody species of similar leaf morphology can be compared with models developed for oblong and elliptical leaves, based on the principle that in potential models, the variation of the intercept coefficient (β0) tended to 0.5 for leaves more elongated to 0.7 in less elongated leaves. While the angular coefficient (β1) tended to vary from 0.97 for less elongated leaves, up to 1 when the relationship between LA is remarkably close to a rectangle. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Simultaneous cultivation of agricultural and forest species may result in changes in plant community interactions, generating microclimatic changes within the understory and then modifying growth and yield characteristics of the intercropping systems. Thus, this study aimed to assess the radiation use efficiency, growth and yield of bean and soybean cultivated in succession under two arrangements of agroforestry and full sun. To these ends, two field experiments were conducted in Southern Brazil: bean in‐season and soybean off‐season. Absolute and relative growth rates, net assimilation rate, leaf weight ratio, leaf area ratio, specific leaf area, radiation use efficiency and yield of bean and soybean were assessed. The solar radiation flux was modified by plant arrangement and tree canopy characteristics. Shading affected growth and yield characteristics and the radiation use efficiency of the studied crops. From the results obtained in this study, it is possible to recommend crop bean cultivation in agroforestry systems. However, for soybean, due to the reduced yields obtained in agroforestry systems, further research should be conducted in order to study more spaced arrangements and crop insertion in the early years of agroforestry, in order to enable its insertion in agroforestry systems in Southern Brazil. [ABSTRACT FROM AUTHOR]

Copyright of Biotropica is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Some plants do not demand a lot of chilling hours, but methods to overcome dormancy promote more vigorous and productive plant. This study aimed to assess hydrogen cyanamide and nitrogen fertilizer with different concentration to growth and production in 'Roxo de Valinhos' fig tree. Two crop cycles (2015/2016 and 2016/2017) was performed in São Manuel city, São Paulo State, Brazil. Phenological and productive data was evaluated in a 2 x 5 factorial (Product x Concentration), organized in randomized complete block design, with three trees by plot. The factor products had as level hydrogen cyanamide and nitrogen fertilizer and the factor concentrations was constituted by 0, 1, 2, 3, and 4%. Furthermore, the following data was evaluated: number of days for budbreak, number of buds per plant, harvest period, branch length and diameter, leaf number, leaf area, number of fruits per plant, fruit mass, production and yield. Results indicated that both products anticipated the sprouting and promoted a higher number of buds overcome the dormancy. Plant production was higher in both cycles when the products were used (2.1 and 2.7, respectively). At last, hydrogen cyanamide showed better outcomes due to the higher number of fruits and production. [ABSTRACT FROM AUTHOR]

Leaf area is an important growth variable in agricultural crops and the leaf is the main variable of interest in the tobacco industry. So, the aim of this scientific research was to estimate the Burley tobacco leaf area by linear dimensions of the leaves and to determine which mathematical model is more adequate for this purpose. Two experiments were carried out with Burley tobacco, cultivar DBH 2252, in 2016/2017 and 2018/2019 agricultural years, respectively, in the municipalities of Itaqui and Vanini - RS - Brazil. In 600 leaves were measured length (L), width (W), length×width product (LW), length/width ratio (L/W) and determined the real leaf area (LA). Four hundred and fifty leaves were separated to generate models of the leaf area as a function of linear dimension and the other 150 leaves were used for model's validation. The power model LA = 0.5037LW1.04435 (R² = 0.9960) is the most adequate for Burley tobacco 'DBH 2252' leaf area estimation. Alternatively, the models LA=2.0369W1.8619 (R²=0.9796) and LA=0.1222L2.2771 (R²=0.9738) based on width and length, respectively, can be used when only one leaf dimension is measured. [ABSTRACT FROM AUTHOR]

Copyright of Revista Caatinga is the property of Revista Caatinga and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sugarcane production in Brazil for the 2019/20 harvest is estimated at approximately 615 million tons. However, in the state of Rio Grande do Sul, it is estimated at only 42.5 thousand tons. It is assumed that the use of diazotrophic bacteria can contribute to the expansion of sugarcane cultivation in the state through increased productivity; hence, this study aimed to evaluate the effects of diazotrophs on the growth of sugarcane. The study was conducted using sugarcane varieties: RB867515, RB92579, RB966928, and RB975932 that were either treated with diazotrophic bacteria or left as a control. The application of diazotrophic bacteria resulted in increased leaf area and stem number in variety RB867515 (cane plant cultivation cycle), and an increase in the relative chlorophyll content of all the varieties of sugarcane except of RB92579. Furthermore, most varieties responded positively in terms of biomass, dry matter, total nitrogen, and soluble solids. These results suggest that the application of diazotrophs assists in the growth and development of sugarcane varieties in Rio Grande do Sul. [ABSTRACT FROM AUTHOR]

Copyright of Revista Caatinga is the property of Revista Caatinga and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Brasileira de Agricultura Irrigada - RBAI is the property of Revista Brasileira de Agricultura Irrigada - RBAI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aims Plants have limited resources for defenses and species that invest in biotic defenses might exhibit leaves that invest less in other types of defenses. We have investigated whether plants that have few mechanical defenses, but have extrafloral nectaries (EFNs) patrolled by ants, are less prone to herbivory, compared with plants without EFNs that have tougher leaves. Methods Data from the literature were extracted to examine the reported levels of herbivory in plants with or without EFNs. In a savanna vegetation in southern Brazil, field data were collected in leaves from six tropical species and herbivory and specific leaf area (SLA) levels were measured. We further evaluated differences in herbivory and SLA among species and between plants with or without EFNs. In order to test the relationship between herbivory and leaf toughness we regressed average herbivory and average SLA per plant. Important Findings Plants exhibited variable levels of leaf damage, but plants without ant defenses experienced the highest levels of leaf area loss to herbivory. Levels of mechanical defenses were also variable among the plant species. Plants without EFNs were tougher, exhibiting lower values of SLA. Although plants without EFNs had more sclerophyllous leaves, this mechanical defense was not sufficient to impair and/or reduce herbivore feeding, suggesting that the biotic defenses performed by patrolling ants might be more effective than investment in mechanical defenses associated with leaf palatability. [ABSTRACT FROM AUTHOR]

Arugula is a crop of fast vegetative growth and short cycle, widely accepted worldwide. In Brazil, its production generates jobs and income for family farming. However, the use of saline water in the cultivation of this plant is one of the main factors that limit production. Given this situation, the objective of this study was to evaluate the growth of Apreciatta arugula cultivated under conditions of shading and salinity levels of irrigation water. The experiment was conducted in a greenhouse in the experimental area of the Agricultural Sciences Center of the Federal University of Alagoas, in the city of Rio Largo, AL. The treatments were obtained from the combination of two shading conditions (with shading and without shading) and five levels of electrical conductivity of the irrigation water (0.5; 2.0; 3.5; 5.0 and 6.5 dS m-1). The experimental design used was completely randomized in a 2 x 5 factorial scheme. Combined, the factors resulted in 10 treatments with four replications and one plant per plot, totaling 40 experimental units. Arugula plants were evaluated for leaf number, plant height, leaf area and dry matter of the aerial part. Increasing levels of salinity in the irrigation water, lead to a reduction in the number of leaves, plant height and dry mass of the aerial part of arugula plants cultivar Apreciatta. However, the use of shading together with the salinity of irrigation water up to 1.4 dS m-1 does not affect the leaf area of arugula plants, being possible to cultivate without considerable losses. [ABSTRACT FROM AUTHOR]