ABSTRACT. Nonlinear regression models represent an alternative way to describe plant growth. In this study, we aimed to model the growth of linseed using four methods for data collection (longitudinal, mean, random, and cross-sectional) and fitting the logistic and Von Bertalanffy nonlinear regression models. The data came from experiments conducted between 2014 and 2020 in the municipality of Curitibanos, Santa Catarina, Brazil. The study had a randomized block design, with experimental units consisting of six lines, 5.0 m long and 3.0 m wide, containing the varieties and cultivars of linseed with four replicates. We performed weekly assessments of the number of secondary stems and plant height and measured total dry mass fortnightly. After tabulation, the data were analyzed using the four methods, and the logistic and Von Bertalanffy models were fitted. The logistic model for the plant height variable exhibited the best performance using the longitudinal, mean, and cross-sectional methods. It was an alternative approach that reduced the time and labor required to conduct the experiment. ABSTRACT longitudinal (longitudinal mean random crosssectional cross sectional 201 202 Curitibanos Catarina Brazil design lines 50 5 0 5. 30 3 3. wide replicates fortnightly tabulation fitted experiment 20 2

ABSTRACT This study aimed to evaluate the use of the product of thermal efficiency and photosynthetically active radiation (TEP) to model the growth of tomato seedlings across different growing seasons. The work was conducted in a completely randomized design with four replicates in two seasons (summer/autumn and winter/spring). Height, diameter, the Dickson’s Quality Index (DQI), and total plant mass (TPM) were measured at 15, 20, 25, 30, 35 and 40 days after sowing (DAS). The logistic model was fitted for each measured variable as a function of TEP, and the partial derivatives of the fitted function estimated the critical points. The results demonstrated that the logistic function effectively explained the nonlinear relationships of seedling growth. The fit quality parameters showed high fitted coefficients of determination and low values for the standard error of fit, residual standard deviation, and intrinsic and parametric nonlinearity. It was possible to characterize the growth process of tomato seedlings in both growth periods investigated. The logistic model fitted for the studied variables as a function of TEP becomes an accurate model capable of describing growth aspects of tomato seedlings, such as growth estimation, growth speed, and growth rate, essential parameters for decision-making in tomato cultivation. (TEP summer/autumn summerautumn summer autumn winter/spring. winterspring winter/spring . winter spring winter/spring) Height diameter Dicksons Dickson s DQI, DQI , (DQI) TPM (TPM 15 20 25 30 3 4 DAS. DAS (DAS) points deviation nonlinearity investigated estimation speed rate decisionmaking decision making cultivation (DQI 1 2 (DAS

RESUMO: A cultura da cenoura se destaca no cenário mundial por suas características nutricionais e importância econômica, aspecto que demanda o constante desenvolvimento de pesquisas visando maior produtividade. Assim, o objetivo deste trabalho foi propor um plano experimental, determinando as estimativas de tamanho de parcela, tamanho de amostra e número de repetições, com a finalidade de aumentar a precisão e confiabilidade dos resultados dos experimentos com a cultura da cenoura. Foram conduzidos seis ensaios de uniformidade, utilizando três cultivares em duas safras (Safra: 2019 e 2021). Cada planta foi considerada uma unidade experimental básica e em cada BEU foram medidas as variáveis altura da parte aérea, comprimento da raiz, massa fresca da parte aérea, massa fresca da raiz e diâmetro da raiz. O tamanho da parcela, da amostra e o número de repetições foram estimados pelo método da máxima curvatura do coeficiente de variação. Os resultados recomendam que para experimentos com a cultura da cenoura sejam utilizadas parcelas com doze plantas. Para amostragem de plantas de cenoura na parcela, devem ser utilizadas amostras de onze plantas no sentido da linha, considerando uma semi-amplitude do intervalo de confiança (D%) igual a 20% da média, com nível de confiança de 95%. Para uma diferença mínima significativa no teste de Tukey expressa em porcentagem da média de 50%, recomendam-se parcelas de doze plantas por fileira de cultivo, com oito repetições. RESUMO econômica produtividade Assim parcela uniformidade Safra (Safra 201 2021. 2021 . 2021) aérea variação linha semiamplitude semi amplitude D% D (D% 20 95 95% 50 50% recomendamse cultivo 202 (D 2 9 5

ABSTRACT: The carrotculture stands out on the world stage due to its nutritional characteristics and economic importance, an aspect that demands the constant development of research aiming greater productivity. Thus, this study proposed an experimental plan, determining the estimates of plot size, sample size, and number of repetitions, with the purpose of increasing the precision and reliability of the results of the experiments with the carrot crop. Six uniformity trials were conducted, using three cultivars in two growing seasons (Season: 2019 and 2021).Each plant was considered a basic experimental unit and in each BEU, the variables shoot height, root length, shoot fresh mass, root fresh mass, and root diameter were measured. The size of the plot, sample, and the number of repetitions was estimated by the method of maximum curvature of the coefficient of variation. The results recommend that for experiments with the carrot crop, plots with twelve plants should be used. For a sampling of carrot plants in the plot, samples of eleven plants must be used in the direction of the row, considering a semi-amplitude of the confidence interval (D%) equal to 20% of the mean, with a confidence level of 95%. For a minimum significant difference in the Tukey test expressed as a percentage of the 50% mean, plots of twelve plants per crop row, with eight replicates, are recommended. ABSTRACT importance productivity Thus plan conducted Season (Season 201 2021.Each 2021Each Each 2021 .Each BEU height length mass measured variation row semiamplitude semi amplitude D% D (D% 20 mean 95 95% 50 replicates recommended 202 (D 2 9 5

RESUMO: O estudo foi conduzido com o intuito de analisar as implicações da remoção dos parâmetros do modelo matemático sobre os resultados da análise de trilha, com aveia cultivada em diferentes anos e cenários agrícolas (com e sem fungicida). Para isso, dois ensaios de campo foram conduzidos no sul do Brasil, em cinco anos de cultivo. O delineamento experimental empregado no ensaio I (com aplicação de fungicida) foi o de blocos completos ao acaso, sendo um bifatorial 22 × 4, caracterizado por vinte e duas cultivares de aveia e quatro aplicações de fungicidas. Para o ensaio II (sem aplicação de fungicida) foi empregado o delineamento em blocos completos ao acaso, sendo os tratamentos caracterizados por vinte e duas cultivares de aveia, com três repetições. Os caracteres mensurados foram comprimento da panícula, massa da panícula, número de espiguetas, número de grãos, massa de grãos e rendimento de grãos. Para cada ano, grupo de dados e cenário foram calculados os coeficientes de correlação entre as variáveis explicativas e a produtividade de grãos. O diagnóstico de multicolinearidade indicou a violação do pressuposto estatístico, sendo necessário proceder a análise de trilha sob multicolinearidade (em crista). A remoção dos parâmetros do modelo matemático promoveu alterações nas relações lineares entre os caracteres de rendimento da aveia, sendo verificado a manutenção no padrão dos coeficientes de correlação linear em 3,30% e 20% das situações, para os cenários com e sem aplicação de fungicida, respectivamente. Com relação aos coeficientes de trilha, foi verificado manutenção na direção e magnitude dos efeitos diretos em 3,30% e 30% e os efeitos indiretos em 7,33% e 24,67% das situações, para os cenários com e sem aplicação de fungicida, respectivamente. RESUMO fungicida. fungicida . isso Brasil cultivo acaso 2 4 fungicidas repetições panícula espiguetas ano estatístico crista. crista crista) 330 3 30 3,30 20 situações respectivamente 733 7 33 7,33 2467 24 67 24,67 3,3 73 7,3 246 6 24,6 3, 7, 24,

ABSTRACT: This study was conducted with the aim of analyzing the implications of removing the parameters from the mathematical model on the results of path analysis, with oats grown in different years and agricultural scenarios (with and without fungicide). For this, two field trials were conducted in southern Brazil, in five years of growth. The experimental design used in trial I (with fungicide application) was randomized complete blocks (RCB), in a 22 × 4 bifactorial arrangement, characterized by twenty-two oat cultivars and four fungicide applications. For trial II (without fungicide application) the RCB design was used, and the treatments were characterized by twenty-two oat cultivars, with three replications. The traits measured were panicle length, panicle mass, number of spikelets, number of grains, grain mass, and grain yield. For each year, data group, and scenario, the correlation coefficients between the explanatory variables and grain yield were calculated. The diagnosis of multicollinearity indicated violation of the statistical assumption, so it was necessary to proceed with a path analysis under multicollinearity (ridge). The removal of parameters from the mathematical model caused changes in the linear relationships between the oat yield traits, with the maintenance of the linear correlation coefficients in 3.30% and 20% of the situations, for the scenarios with and without fungicide application, respectively. Regarding the path coefficients, it was observed that the direct effects were maintained in 3.30% and 30% and indirect effects in 7.33% and 24.67% of the situations, for the scenarios with and without fungicide application, respectively. ABSTRACT fungicide. . fungicide) this Brazil growth application RCB, , (RCB) 2 arrangement twentytwo twenty applications replications length mass spikelets grains year group scenario calculated assumption ridge. ridge (ridge) 330 3 30 3.30 20 situations respectively 733 7 33 7.33 2467 24 67 24.67 (RCB (ridge 3.3 73 7.3 246 6 24.6 3. 7. 24.

RESUMO O conhecimento das interações planta-atmosfera é essencial para compreender o crescimento e desenvolvimento das culturas. Assim, o ajuste de curvas de crescimento é metodologia importante para modelar o crescimento das plantas e seus estágios fenológicos. O estudo teve por objetivo descrever o crescimento de quatro materiais de linhaça cultivados em seis anos agrícolas e em diferentes épocas de semeadura por meio do modelo logístico. Nove experimentos foram conduzidos em Curitibanos, SC, Brasil, entre 2014 e 2020, considerando diferentes épocas de semeadura. Durante o ciclo da cultura, foram avaliados número de folhas, número de caules secundários, altura da planta e massa seca total. O modelo logístico foi ajustado considerando as variáveis de crescimento como dependentes e a soma térmica acumulada como independente. O ajuste do modelo e estimação dos parâmetros foram obtidos pelo método dos mínimos quadrados ordinários. A qualidade do ajuste foi mensurada por não linearidade intrínseca e paramétrica, coeficiente de determinação ajustado, erro padrão aleatório, desvio padrão do ajuste, critério de informação de Akaike e critério de informação Bayesiano. O desempenho do modelo logístico divergiu entre as variedades e cultivares, em diferentes anos e épocas de semeadura. Contudo, o uso do modelo logístico melhora as inferências sobre o crescimento da linhaça e, as estimativas de seus parâmetros e pontos críticos permitem uma interpretação biológica e prática a fim de auxiliar no planejamento da cultura. Ainda, o estudo sugere que o ciclo da linhaça está relacionado às interações genótipo× ambiente, sendo que em semeaduras tardias, os ciclos tendem a encurtar. plantaatmosfera atmosfera culturas Assim fenológicos Curitibanos SC Brasil 201 2020 cultura folhas secundários total independente ordinários paramétrica aleatório Bayesiano cultivares Contudo Ainda genótipo ambiente tardias encurtar 20 202 2

ABSTRACT Knowledge on plant-atmosphere interactions is essential to understand the growth and development of agricultural crops. Thus, fitting growth curves is an important methodology to model plant growth and phenological stages. The study aimed to describe the growth of four oilseed flax materials cultivated in six agricultural years and with different sowing dates through the nonlinear logistic model. Nine experiments were carried out in Curitibanos, SC, Brazil, between 2014 and 2020, considering different sowing dates. Throughout the crop cycle, the number of leaves, number of secondary stems, plant height and total dry mass were measured. Nonlinear logistic model was fitted to the data, with the growth variables as the dependent variables and the accumulated thermal sum as the independent variable. Model fit and parameter estimation were obtained by ordinary least method, using a Gauss-Newton algorithm. The goodness of fit was measured by intrinsic and parametric nonlinearity, adjusted coefficient of determination, random standard error, standard deviation of fit, Akaike information criterion, and Bayesian information criterion. The performance of the nonlinear logistic model differed between the varieties and cultivars studied, in different years and sowing times. However, the use of the nonlinear logistic model improves inferences about the growth of oilseed flax, and the estimates of its parameters and critical points allow a biological and practical interpretation to assist in crop planning. Furthermore, the study suggests that the oilseed flax cycle is directly related to genotype × environment interactions, and when sown at later times, the materials tend to shorten their cycle. plantatmosphere atmosphere crops Thus stages Curitibanos SC Brazil 201 2020 leaves stems data variable method GaussNewton Gauss Newton algorithm nonlinearity determination error criterion studied times However planning Furthermore 20 202 2

RESUMO Pisum sativum L. é uma cultura multiuso, cuja duração de seu período vegetativo e reprodutivo é determinada pela combinação de temperatura, umidade e resposta do genótipo a essas condições. Diante do exposto, visando minimizar as perdas de produtividade por condições adversas em períodos sensíveis da cultura, o objetivo foi avaliar o desenvolvimento fenológico e a produção de Pisum sativum L. em diferentes épocas de cultivo. Utilizou-se o delineamento em blocos casualizados, com cinco estações de cultivo, quatro repetições e oito plantas por unidade experimental. As variáveis analisadas foram: plastocrono, número de dias para início da floração, plena floração e início da colheita, soma térmica acumulada para início da floração, plena floração e início da colheita, número de vagens, massa de vagens e produtividade total por unidade de área. A análise de variância foi realizada e as médias comparadas pelo teste de Scott Knott. Também foi realizada a análise de componentes principais da matriz de correlação de Pearson’s das variáveis fenológicas e de produção. Nas estações 1, 4 e 5, as plantas atingiram a plena floração mais cedo e a massa de vagens foi consideravelmente menor, resultando em menores rendimentos. As estações 2 e 3 foram as mais produtivas e apresentaram menores resultados para o plastocrono, menor soma térmica até a plena floração e fotoperíodo mais curto, o que aliado às baixas temperaturas durante o ciclo vegetativo, resultou em um ciclo de cultivo mais longo. L multiuso temperatura exposto Utilizouse Utilizou se casualizados experimental plastocrono colheita área Knott Pearsons Pearson s 1 5 rendimentos curto longo

ABSTRACT Pisum sativum L. is a multi-purpose crop. The duration of its vegetative and reproductive periods is determined by a combination of temperature and humidity and genotype response to these conditions. To minimize the loss of productivity due to adverse conditions in sensitive periods of the crop, we evaluated the phenological development and production of Pisum sativum L. in different growing seasons. We used a randomized block design, and the experiments were conducted across five growing seasons, with four replications and eight plants per experimental unit. The variables analyzed were as follows: plastochron, number of days to start flowering, full flowering, and beginning of harvest, the accumulated thermal sum to start flowering, full flowering, and beginning of harvest, and the number of pods, pod mass, and total productivity per unit area. The analysis of variance was performed, and the mean values of the data were compared using the Scott-Knott test. Principal component analysis was also performed from Pearson’s correlation matrix of phenological and production variables. In seasons 1, 4, and 5, the plants reached full flowering earlier, and the pod mass was considerably lower, resulting in lower yields. Seasons 2 and 3 were the most productive and showed lower results for plastochron, less thermal sum until full flowering, and a shorter photoperiod, which, combined with low temperatures during the growing season, resulted in a longer cultivation cycle. L multipurpose multi purpose crop design follows plastochron harvest pods area ScottKnott Scott Knott test Pearsons Pearson s 1 4 5 earlier yields photoperiod which season cycle

RESUMO O manejo do nitrogênio analisando indicadores agronômicos e ambientais garante produtividade satisfatória com maior qualidade ambiental. O objetivo neste estudo é propor um manejo mais sustentável de uso do nitrogênio em trigo, considerando o fornecimento em dose cheia e fracionada com estimativa da eficiência técnica, econômica e de expectativa de produtividade. Dois experimentos foram conduzidos, um para quantificar a produtividade de biomassa e outro, para avaliação do rendimento de grãos. O delineamento experimental foi o de blocos casualizados com quatro repetições em fatorial 5 × 3, para doses de N-fertilizante (0, 30, 60, 90 e 120 kg ha-1) e forma de fornecimento do nutriente [condição cheia (100%) no estádio fenológico V3 (terceira folha expandida); fracionada (70/30%) no estádio fenológico V3/V6 (terceira e sexta folha expandida) e; fracionada (70/30%) no estádio fenológico V3/R1 (início da antese)], respectivamente. O manejo mais sustentável do nitrogênio em trigo é obtido com a dose de expectativa de produtividade de 3 t ha-1 pela adubação manual, com o nutriente fornecido em dose cheia no estádio fenológico V3.

ABSTRACT The management of nitrogen by the assessment of agronomic and environmental indicators ensures satisfactory productivity with higher environmental quality. The objective of this study was to propose more sustainable management of nitrogen use in wheat, considering the supply of full and fractioned doses with an estimate of technical, economic efficiency, and expected productivity. Two experiments were conducted, one to quantify biomass productivity and the other to evaluate grain yield. The experimental design consisted of a randomized block with four repetitions in a 5 × 3 factorial, for N-fertilizer doses (0, 30, 60, 90, and 120 kg ha-1) and nutrient supply form [full condition (100%) in the phenological stage V3 (the third leaf expanded); fractionated (70/30%) in the phenological stage V3/V6 (third and sixth leaf expanded) and; fractionated (70/30%) in the phenological stage V3/R1 (beginning of anthesis)], respectively. The most sustainable management of nitrogen in wheat was obtained with the expected yield rate of 3 t ha-1 by manual fertilization, with nitrogen supplied in full dose at the V3 phenological stage.

Abstract The objective of this work was to evaluate the influence of colored shade mesh and plant density on the morphological characteristics of Corymbia citriodora seedlings. The highest radiation efficiency was found in the blue mesh, 7.01 g MJ-1 and 5.72 g MJ-1 for average and high density respectively. For dry matter and leaf area index at high density, the treatment without mesh followed by the red mesh was the best. The chlorophyll index did not differ between treatments, with mean values of 206.4, 59.1 and 262.0 for chlorophyll a, b and total, respectively. Using principal component analysis, we found the total variance to be 70%. The use of colored shade mesh and plant density altered the radiation use efficiency and dry matter accumulation. Leaf area index was affected only by plant density. The red mesh resulted in the most similar values to the treatment without mesh.

RESUMO: O objetivo deste trabalho foi determinar a variável meteorológica com maior contribuição na produtividade de colmos de cana-de-açúcar na região noroeste e central do Rio Grande do Sul. Os genótipos de cana-de-açúcar utilizados foram: UFSM XIKA FW, UFSM LUCI FW, UFSM PRETA FW, UFSM DINA FW, UFSM MARI FW, IAC87-3396. As cultivares UFSM são provenientes do processo de mutação do programa de melhoramento da Universidade Federal de Santa Maria, campus de Frederico Westphalen, e possuem tolerância a baixas temperaturas. Os caracteres morfológicos responsáveis pela produtividade utilizados nos modelos foram diâmetro médio de colmo, número médio de colmos por metro de sulco e estatura média de colmos. As variáveis meteorológicas utilizadas foram a temperatura mínima do ar, precipitação pluviométrica, radiação solar incidente e soma térmica acumulada. Foi realizada a correlação de Pearson, correlações canônicas e regressão de Stepwise entre os caracteres morfológicos e as variáveis meteorológicas, nos quais foi constado que a temperatura mínima do ar é a variável com maior influência na produtividade da cana-de-açúcar nas regiões estudadas e, que a soma térmica acumulada é a variável com maior correlação e contribuição no diâmetro de colmo e estatura média dos colmos. Desse modo, os modelos indicam que o crescimento da cana-de-açúcar responde de forma positiva a soma térmica acumulada, e as regiões em estudo apresentam potencial para o cultivo da cana-de-açúcar.

ABSTRACT: This study determined the meteorological variable that most contribute to the productivity of sugarcane stalks in the northwest and central regions of Rio Grande do Sul. The following sugarcane genotypes were used: UFSM XIKA FW, UFSM LUCI FW, UFSM PRETA FW, UFSM DINA FW, UFSM MARI FW, and IAC87-3396. The UFSM cultivars originate from a mutation process in the breeding program conducted at the Federal University of Santa Maria, Frederico Westphalen campus, and have low temperature tolerance. The productivity-associated morphological characters included in the models were average stem diameter, average stem number per meter of furrow, and average stem height. The following meteorological variables were used: minimum air temperature, precipitation, incident solar radiation, and accumulated thermal sum. Pearson’s correlation, canonical correlations, and Stepwise regression were performed between morphological characters and meteorological variables: minimum air temperature had the greatest influence on sugarcane productivity in the studied regions, and accumulated thermal sum showed the highest correlation and contributed most to stem diameter and average stem height. Thus, the models indicated that the growth of sugarcane is positively associated with the accumulated thermal sum, and sugarcane can be cultivated at the studied regions.

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 Aloysia triphylla is an aromatic plant used in several industrial sectors, owing to the chemical properties of its essential oil. Biosynthesis of organic compounds is influenced by the growth conditions. As such, temporal and spatial variation affect the chemical composition of essential oils. We hypothesized that: i) the chemical composition of A. triphylla essential oil is influenced by differences in irrigation and season; and ii) the major components of A. triphylla essential oil do not vary between treatment conditions. To test these hypotheses, we determined the chemical composition of A. triphylla essential oil as a function of four seasons crossed with four irrigation levels. A completely randomized experimental design with a randomized block in a 4 × 4 factorial scheme, representing the four seasons of the year (summer, autumn, winter, and spring) and four irrigation levels (50%, 75%, 100%, and 125% of the reference evapotranspiration), was used with four replicates. Our results show that the chemical composition of A. triphylla essential oil varied with the two study factors, of which season was the major factor. The highest concentrations of constituents classified as monoterpene and sesquiterpene were observed in the summer season, and the highest constituents of the other group of compounds were observed in winter. In addition, the major components of the essential oil were α-citral, limonene, and β-citral, and their levels were the highest during winter.

Abstract: Despite its economic importance, the microclimate in soybean canopies has not yet been studied in detail. Such a study can yield valuable information regarding the interaction of a crop with its environment. In this context, the aim of this study was to evaluate the solar radiation dynamic and yield responses for each canopy strata for two soybean cultivars with determined and undetermined growth habits. A field study was conducted during the 2013/2014 and 2014/2015 growing seasons in the city of Frederico Westphalen, Rio Grande do Sul, Brazil. The cultivar NA6411, with a determinate growth habit, presented a greater interception of radiation in the middle and lower canopies strata which results in higher soybean yield when compared to the cultivar TEC6029, and thus, can be recommended for cultivation in crop production systems. The contribution of the middle and upper canopy strata to the total yield formation was greater than that observed in the lower canopy strata due to the greater interception of solar radiation by these strata. To increase soybean yields, new studies regarding the microclimatic conditions of the soybean canopy should be developed to improve the maximum potential yield of the new soybean cultivars.

Abstract: The objective of the study was to evaluate the growth and production efficiency of forage-grain dual-purpose wheat in two arrangements and four agroforestry systems (Intercrop-I and Intercrop-II), as well as to evaluate crop management for the wheat crops in two planting seasons (Crop Season I-2014 and Crop Season II-2015. The experiment was conducted in a randomized complete block design, factorial scheme 7x2x2, with seven cultivation systems Eucalyptus urophylla x Eucalyptus grandis Intercrop-II and Intercrop-I; Peltophorum dubium Intercrop-II and Intercrop-I; P. rigida Intercrop-I; S. parahyba Intercrop-I; a wheat monoculture with no tree species present; and two harvest management techniques (with and without harvesting of the forage species). Agroforestry systems generated shading for wheat plants, with a higher phyllochron and lower values of leaf area index of those individuals kept under trees with higher crown shading (non-deciduous trees) due to the lower transmissivity of solar radiation. The systems composed with Schizolobium parahyba in Intercrop-I and Parapiptadenia rigida in Intercrop-I provide a minor phyllochron to the wheat, resulting in a higher leaf area index and dry matter yield. Thus, the cultivation of tree species and dual-skilled agricultural crops, such as wheat, provides promising alternatives for the future use of land in tropical countries.

Abstract Sugarcane (Sacharum officinarum L.) monocropping has had a great socio-economic and environmental impact in Brazil, and agroforestry systems have been considered as an alternative for more sustainable production; however, there is a lack of field research under such conditions. The aim of this study was to evaluate the growth rates, radiation use efficiency and yield traits in sugarcane cultivated in the understory of Aleurites fordii, in two agroforestry arrangements and monocropping systems. A field experiment was conducted from July 2015 to June 2016 in the city of Frederico Westphalen, Rio Grande do Sul, Brazil. The radiation use efficiency, assimilate partitioning, leaf area index, absolute growth rate, net assimilation rate, number of tillers, plant height, % of intercepted solar radiation, extinction coefficient, and yield in each system was evaluated. In agroforestry systems, the dynamic interactions between multiple plant species change with the time and can result in unique microclimates. The use of agroforestry systems in 12 x 12m arrangements should be prioritized because it enables greater yields and radiation availability in the understory. This study sought to provide new sustainable alternatives for farmers in order to increase the diversification of the rural property and maintain the preservation of existing agroecosystems.

Abstract Soybean (Glycine max L.) monocropping have had a great socio-economic and environmental impact on the world and agroforestry systems has been considered an alternative for more sustainable production. The aim of this study was to evaluate the effect of different arrangements of agroforestry systems of the species E. urophylla x E. grandis and P. dubium and the pruning of the trees on the dynamics of solar radiation and soybean yield. A field experiment was conducted in Southern Brazil. In order to achieve the objective of the study, the solar radiation transmissivity and the productive performance of the soybean were evaluated. In this study, the soybean yield was determined by the arrangement of the agroforestry system and forest species utilized. The soybean crop cultivated in the understory of the P. dubium trees showed the highest yield response. The use of silvicultural practices for the management of forest species should be considered to generate the balance of the productive system. In this context, tree pruning is a viable side for agroforestry systems, as it promotes an increase in the incidence of solar radiation in the understory, resulting in an increase in soybean yield, especially when integrated with P. dubium.