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A soja tem apresentado aumento de produtividade nos últimos anos e o manejo adequado das plantas tem melhorado a qualidade fisiológica das sementes. A aplicação com micronutrientes, especialmente molibdênio (Mo) e níquel (Ni) tem importante estratégia para aumentar o rendimento de grãos. Este estudo teve como objetivo avaliar os efeitos da aplicação foliar de Mo e Ni sobre o teor foliar de nitrogênio (N), qualidade da germinação (protrusão radicular, envelhecimento em termos de vigor, germinação e tamanho de plântulas) e tamanho de sementes de soja cultivadas sob duas condições edafoclimáticas. Os tratamentos consistiram em quatro doses de Mo (0, 400, 800 e 1600 g ha-1) e três doses de Ni (0, 60 e 120 g ha-1) aplicadas no início do estádio reprodutivo (R1 e R2). Os plantios foram realizados em Londrina (Brasmax Desafio RR) e Selviria (TMG 7063 IPRO e Brasmax Desafio RR). A protrusão radicular, vigor e tamanho das plântulas foram influenciados pela aplicação foliar de Mo, enquanto a aplicação de Ni em altas doses diminuiu a protrusão radicular. A aplicação de Mo influenciou positivamente o teor de N, tamanho dos grãos e qualidade fisiológica das sementes na dose de 800–1600 g ha-1.

Abstract Background and aims Nano-zinc (Zn) fertilizer is an easily adaptable and environmentally safe alternative option that can effectively improve growth, yield and biofortification of common bean. Plant growth-promoting bacteria (PGPBs) could promote plant growth and nutrients availability in sustainable manner. Therefore, this study aimed to investigate the influence of foliar nano-Zn application in association with seed co-inoculations of PGPBs on growth, yield, biofortification and Zn use efficiencies in common bean cultivation. Two field experiments were performed with seven co-inoculations of PGPBs and three foliar nano-Zn doses applied 50% at R5 and 50% at R8 stages of common bean to determine plant height, shoot dry matter, grain yield, Zn concentration and uptake in shoot and grains, Zn partitioning index, daily Zn intake and Zn use efficiencies for agronomic biofortification. Results The combined foliar nano-Zn application and co-inoculation of R. tropici + B. subtilis enhance grain yield, leaf chlorophyll index, total protein content, grain Zn concentration and uptake, daily Zn intake, Zn use efficiency, applied Zn recovery and Zn utilization efficiency in common beans in 2019 and 2020 cropping seasons. Foliar nano-Zn application at a dose of 1.5 kg ha−1 increased plant height, shoot dry matter, shoot Zn uptake, Zn partitioning and agro-physiological efficiency under co-inoculation with R. tropici + B. subtilis in both cropping years. Conclusions The treatments with foliar nano-Zn application at a dose of 1.5 ha−1 and co-inoculation with R. tropici + B. subtilis improved performance, chlorophyll index, protein content, grain yield, and Zn efficiencies that can lead to better biofortification of common bean in tropical savannah. Therefore, it is recommended that applying nano-Zn via foliar along with co-inoculation of PGPBs could be the better option for productivity and biofortification of common bean. Graphical Abstract

The selection of an appropriate nitrogen (N) source can mitigate the negative effect of root-knot nematodes on the yield of common beans. A greenhouse experiment was conducted to assess the application efficiency of four N sources (urea, ammonium sulfate, ammonium nitrate, and sodium nitrate) and inoculation with Rhizobium tropici on the yield components, chlorophyll, and total nitrogen (N) leaf contents of four common bean cultivars (IDR Curió, IDR Sabiá, IDR Tuiuiú, and IDR Bem-te-vi). These beans were cultivated in substrates both infected and uninfected with Meloidogyne incognita. In the soil containing phytonematodes, the IDR Curió cultivar exhibited the highest shoot and root dry weight yield, resulting in the greatest root volume, total N content, and grain yield. Among the N sources, the application of either urea or ammonium sulfate proved the most effective in enhancing common bean productivity in soil, irrespective of the cultivar or whether the soil was infected with Meloidogyne incognita.

Abstract The objective of this work was to evaluate the application of silicate ultramafic alkaline rock, with different granulometry, as an alternative potassium source on the increase of soil fertility and on the nutritional status and biomass yield of the alfalfa and centrosema crops. The used soil was a Typic Ultisol with 27.4 mg dm-3 K and 733 g kg-1 clay. The experimental design was completely randomized, in a 4 × 2 + 1 factorial arrangement. The treatments consisted of two granulometries (

Micronutrient fertilization is usually neglected by producers, especially for peanut, a crop that is frequently grown in crop rotation systems due to its low perceived nutrient requirements. New peanut cultivars are able to achieve high yields when grown under suitable conditions. However, fertilization recommendation tables are dated and do not consider the need for micronutrients. To support improvements in these recommendations, this study quantified the micronutrient demand (B, Cu, Fe, Mn, and Zn) of three runner peanut cultivars (IAC Runner 886, IAC 505, and IAC OL3) during the biological cycle and the transport of these micronutrients to pods and kernels. The experiment was carried out in a randomized complete block with a split-plot design and nine replications. The whole plots consisted of the three peanut cultivars, and the subplots comprised nine plant samplings (at 14, 28, 42, 56, 70, 84, 105, 126, and 147 days after emergence (DAE)). These modern peanut cultivars exhibited high uptake and accumulation of Fe, but the proportion of Fe removed by pods and kernels was lowest among all analyzed micronutrients. The second-most-accumulated micronutrient was Mn. The maximum requirement for micronutrients of peanut occurred around 84 DAE, and IAC 505 had the highest micronutrient uptake and accumulation among the cultivars (especially at later stages), followed by IAC OL3 and IAC Runner 886. Our results provide new insights into micronutrient requirements for peanut and demonstrate the need for new fertilizer recommendation programs for peanut cultivation.

Abstract: Soybean has shown increasing performance in terms of yield in recent years. However, despite this growth, the lack of quality control and knowledge about the effects of the nutritional status of plants has compromised the germination and vigor of a significant proportion of seeds. The aim of this study was to evaluate the physiological performance of seeds and root growth of soybean cultivated with boron (B) sources with different solubilities incorporated into the soil. The experimental design was completely randomized in a 2×5 factorial arrangement, with two B sources (boric acid and ulexite) and five B rates (0, 2, 4, 8, and 16 mg.kg-1). 100-seed weight (100SW), germination, seedling shoot length (SSL), seedling root length (SRL), accelerated aging (AA), root protrusion (RP), lignin content in the seed coat (LCSC), and root volume (RV) were evaluated. The B sources and rates showed a significant interaction with increases in RV, RP, SSL, SRL, and 100SW, while the LCSC decreased with increasing rates with no interaction effect, indicating a reduction of seed quality with rates up to 8.0 mg.kg-1, regardless of the B source used.

Entre as espécies de fitonematoides que provocam perdas de produção à cultura da soja estão os nematoides da haste verde (Aphelenchoides besseyi) e o das galhas (Meloidogyne incognita). Diante disso, o objetivo deste trabalho foi estudar os efeitos de diferentes níveis populacionais de A. besseyi e M. incognita na soja. O experimento foi realizado com nove combinações de diferentes níveis populacionais dos nematoides (T1 – Controle não inoculado, T2 - A. besseyi 500 indivíduos, T3 - M. incognita 2000 indivíduos, T4 - A. besseyi + M. incognita 250 + 2000 indivíduos, T5 - A. besseyi + M. incognita 500 + 2000 indivíduos, T6 - A. besseyi + M. incognita 250 + 4000 indivíduos, T7 - A. besseyi + M. incognita 500 + 4000 indivíduos, T8 - A. besseyi + M. incognita 250 + 8000 indivíduos, T9 - A. besseyi + M. incognita 500 + 8000 indivíduos e T10 - A. besseyi + M. incognita 1000 + 8000 indivíduos) e seis repetições. As variáveis analisadas foram: altura de planta, massa fresca da parte aérea (MPA), massa fresca de raízes (MR), número de vagens (V), massa fresca de vagens (MV), número de grãos (G), massa fresca de grãos (MG), quantidade de A. besseyi na parte aérea e de M. incognita nas raízes. O mapa de calor indicou que populações iniciais inoculadas de 500 A. besseyi + 8000 M. incognita apresentou maiores danos ao desenvolvimento da soja, reduzindo todas as variáveis analisadas. As variáveis MG, G e V reduziram na presença de diferentes densidades populacionais das espécies de fitonematoides nematoides, influenciando negativamente o desenvolvimento da soja.

In an effort to improve fertility, recover degraded areas and increase support for the capacity of livestock on pasture, new forms of fertilizer are being developed. Polymer-coated monoammonium phosphate (MAP) is an innovative source of phosphorus (P) for maintaining forage grass productivity. The aim this study was to evaluate the agronomic efficiency of P rates with the presence and absence of the polymer on the productivity, development and nutritional value of hybrid signalgrass (Urochloa spp.) cv. Mavuno. The field research was conducted on a dystrophic Ultisol. The experiment was arranged in a randomized complete block design with four replications and treatments applied in a factorial scheme (2 × 4) + 1. The treatments included two P sources (uncoated MAP and polymers-coated MAP) at four rates (20, 40, 80 and 160 kg ha−1 of P2O5), and the control received no P fertilization. The measured variables showed no differences between sources with or without polymer. The maximum production of accumulated shoot dry weight yield (SDWY) of the ‘Mavuno’ grass was 20.2 Mg ha−1 with the dose of 114 kg ha−1 of P2O5. The value of crude protein and in vitro dry matter digestibility showed a quadratic response with maximum production of 76.5% and 15.9% for the P2O5 rates of 37.2 and 91.1 kg ha−1, respectively, while the acid detergent insoluble fiber showed a linear increase up to the rate of 80 kg ha−1 of P2O5. No differences were observed in plant height, number of tillers, or the relative chlorophyll content between treatments.

This study evaluated the combined effect of foliar spray inoculation with plant growth-promoting bacteria (PGPB) and nitrogen doses on the yield, development, and nutritive value of Megathyrsus maximus cv. BRS Zuri. The experimental design was randomized blocks with four replications, with repeated measures in time. Foliar inoculation of two bacteria (Azospirillum brasilense Ab-V5 (CNPSo 2083) and Ab-V6 (CNPSo 2084) and Pseudomonas fluorescens (CNPSo 2799)) and 40 and 80 kg ha−1 N (urea) rates, in addition to the control (without inoculation and N fertilization), were applied. In the rainy season, at the level of 40 kg ha−1 of N, inoculation of both A. brasilense and P. fluorescens increased, respectively, the tiller number by 33% and 25% (22 February), and the N accumulated in tissues by 42% and 25% (22 January), while in the previous year (21 February) the beneficial effects of both bacteria were observed in the percentage of leaf blade and in the true digestibility in vitro. When the foliar spray was inoculated with A. brasilense Ab-V5 and Ab-V6 and P. fluorescens CNPSo 2799, with 80 kg N ha−1, the root system of Zuri grass increased by 61% and 30%, respectively.

Sulfur deficiency in soils has become a worldwide concern for agricultural production. This study aimed to evaluate the concequence of variable sulfur source and dosing on the nutritional status and production of Piatã forage in a dystrophic Ultisol. The experiment was arranged in a completely randomized block design with four replications. The 4 x 5 factorial treatments consisted of four sulfur sources (elemental sulfur pastilles [ESPA], gypsum [GY], gypsite [GI], and elemental sulfur powder [ESPO]) and five sulfur doses (0, 50, 100, 150. and 200 mg kg-1). The sulfur applications resulted in similar maximum shoot dry mass (SDM) production (16.66 to 17.69 g pot-1) with all sources. However, Piatã grass achieved maximum production in the treatments with 112 mg kg-1 of GI, 118 mg kg-1 of GY and ESPA, and 146 mg kg-1 of ESPO. The number of tillers, the leaf:stem ratio, and SPAD increased with increasing sulfur dose. The greatest increments of root dry mass (RDM) and of the tiller number were obtained with the ESPO source. Macronutrient concentrations in shoot dry mass tissue were in the order K > N > Ca > P > S > Mg. Low sulfur supply resulted in decreased Piatã grass growth with all sulfur sources tested. Differential responses were found with applications of different sulfur sources for SDM, RDM, and tillers number. The sources did not alter the leaf:stem ratio or SPAD index.

Mato Grosso do Sul State in Brazil is characterized by the ‘Cerrado’ ecoregion, which is the most biologically rich Savannah globally. In agricultural terms, the region produces several commodities that are exported around the world. This level of productivity has been achieved through the large-scale use of synthetic fertilizers, which has created several economic and environmental concerns. New approaches in soil fertility management are required to avoid environmental degradation, pollution, and socio-environmental damages. A field experiment, lasting two years, was conducted to investigate the composted sewage sludge (CSS) effects on an infertile acidic soil (Oxisol) planted to maize (Zea mays L.). The following complete randomized complete block design with a 4 × 2 + 2 factorial scheme (four replications) was applied: four CSS increasing rates (from 5.0 to 12.5 Mg ha−1, w.b.) following two application methods (whole area and between crop rows). A control, without CSS or synthetic fertilizers, and conventional synthetic fertilization without CSS were also investigated. Evaluated parameters were: (i) soil and leaf micronutrient concentrations; (ii) maize development, yield, and production. The CSS application increased: (i) the concentration of micronutrients in both soil and leaves; and (ii) the crop yield. Both were particularly true at the higher CSS applied rates. Such organic fertilizer can be safely used as a source of micronutrients for crops as an important low-cost and environmentally friendly alternative to mineral fertilizers, thus safeguarding soil health.

A geoestatística é uma das principais técnicas utilizadas para determinar a variabilidade espacial dos atributos do solo. O objetivo deste trabalho foi comparar o uso de semivariogramas elaborados através do acompanhamento paramétrico da geoestatística e seu pressuposto modelo realizado automaticamente por software na confecção dos mapas de fertilidade do solo. Foram comparados os mapas dos valores de pH, fósforo (P), potássio (K+), cálcio (Ca2+), magnésio (Mg2+), enxofre (SO42-) e saturação por bases (V%), provenientes de 60 amostras coletadas de área de Latossolo Vermelho Distrófico coletadas na profundidade 0-20 cm e malha de 300 m de distância entre os pontos. Os mapas foram comparados por matrizes de erro e avaliadas pelos índices Exatidão Global, Kappa e Tau. O uso de semivariogramas parametrizados e seu pressuposto modelo automático do software não apresentaram alta coincidência para os teores de P disponível e Mg2+, sendo necessário ajustes das variáveis dos semivariogramas na análise espacial em função dos outliers, soma dos quadrados dos resíduos, coeficiente de determinação e validação cruzada para melhor representação da variabilidade dos dados e assim, evitar distorções do alcance do ponto amostral para uma boa representatividade dos atributos estudados, o que contraria o modelo automático gerado pelo software.

Improvements in soybean (Glycine max [L.] Merrill) and wheat (Triticum aestivum L.) yields in cropping systems under no-till management (NTM) in the subtropics have been obtained through advances in phosphorus (P) utilization, cultivar selection, and planting and harvesting strategies. This fact, along with the P application in band application in consolidated planting, has resulted in adequate P utilization efficiency and small depleted soil P levels. The aim of this study was to evaluate the efficiency of P2O5 rates and application methods in soybean-wheat cropping under NTM during two growing seasons (2014–2016) in a Typical Eutrorthox. Four P2O5 rates (0, 30, 60, and 120 kg ha−1) of triple superphosphate (45% P2O5) were applied using two application methods (broadcast and band application at sowing) before the soybean and wheat crops were cultivated. Both P application methods resulted in a significant yield response to P2O5 rates for the soybean and wheat crops. Under NTM, broadcast P2O5 application was more effective than band application in soybean, and maximum grain yields were obtained with 129.3 and 88.1 kg P2O5 ha−1, respectively. Maximum wheat grain yields were obtained with 91.8 and 99.7 kg P2O5 ha−1 for broadcast and band application, respectively. Except for total P in leaves, nutrient uptake and yield components were not affected by the P application methods and rates. The results suggested that in soils with adequate available P levels of >15 mg kg−1 (Mehlich 1 extractant), the grain yield is equivalent or superior with broadcast P application as compared with band application for both soybean and wheat crops when cultivated in a Typical Eutrorthox under subtropical conditions. However, broadcast application is considered more effective for large areas of grain cultivation, where it is necessary to sow crops uniformly within the shortest possible time.

ABSTRACT This study evaluated the nutritional quality, yield, and storage protein modulation in soybean grains in response to levels and sources of sulfur (S) in a dystrophic Ultisol. We used five levels of S (0, 50, 100, 150 and 200 mg kg –1 ) and four sources of S (elemental S pastille - ESPA, gypsum - GY, gypsite - GI and elemental S powder - ESPO). Plants treated with 50 mg kg –1 of GY, GI, and ESPO and 200 mg kg –1 of ESPA had the largest grain yield values. Low S supply resulted in lower yields for all S sources tested. Sulfur deficiencies were observed at all levels for ESPA, resulting in lower concentrations of globulin and higher concentration of glutelin and albumin in the grains, possibly because the S content in the leaf was below the range adequate for soybean, leading to in lower yield values. In general, the application of S sources (GY, GI, and ESPO) increased all protein fractions. The results show that proper application of S is essential to optimize soybean yield and increase storage proteins in the grains. The granulometry of ESPA and ESPO fertilizers was a key factor for the availability of S to soybean plants. This study presents relevant information on S fertilization of soybeans, which could provide better grain nutritional quality and increased storage proteins with benefits to animal health.

Plant-growth-promoting bacteria can be used for sustainable forage grass production while increasing nutrition and biomass. Most of the soils under pasture in the tropics have a degradation level that impairs the forage yield potential, especially because of mismanagement and lack of fertilization. The objective of this work was to evaluate the seed inoculation effects of Azospirillum brasilense on the shoot and root dry mass production and nutritional status of Urochloa brizantha cv. ‘Marandu’ under field conditions for two years in a low-fertility soil. The experimental design was a randomized block design with four replications, arranged in a 2 × 3 factorial scheme, comprised of two doses of A. brasilense (0 and 200 mL ha-1) in combination with three doses of N (0, 25 and 50 kg ha-1). Seed inoculation increased shoot dry mass by 13% in the first year and by 6% in the second year, whereas N application increased dry mass by 27% and 35% in the first and second year, respectively. The concentration of nutrients in the shoots did not change due to the inoculation, but N fertilization affected P, Mg, Fe, Mn, and Zn in the first year and N, P and Cu in the second year. Root dry mass increased 36% with fertilization of 25 kg N ha-1 plus inoculation in relation to the other treatments in the first year. In the second year, the inoculation of A. brasilense increased by 17%. Therefore, seed inoculation of Urochloa brizantha cv. ‘Marandu’ with Azospirillum brasilense increased root and shoot dry mass production in some cuts without influencing tiller numbers. Nitrogen fertilization altered N, Mg, P, Fe, Mn, Zn, and Cu concentrations in shoot dry mass.

O sistema de mudas pré-brotadas (MPB) de cana-de-açúcar é uma nova tecnologia de multiplicação que contribui para a rápida produção de mudas, associando elevado padrão de fitossanidade, vigor e uniformidade de plantio, bem como drástica redução na utilização de mudas por área. Por outro lado, a torta de filtro pode ser uma aliada no desenvolvimento dessa tecnologia que necessita de elevada umidade no período inicial de crescimento. Assim, esse trabalho teve como objetivo avaliar o desenvolvimento de mudas pré-brotadas de cana-de-açúcar sob diferentes quantidades de torta de filtro e modos de aplicação. Os tratamentos foram cinco doses de torta de filtro, equivalentes a 0; 7,5; 15; 30; 45 ton. ha-1 e duas formas de aplicação: em profundidade (0,30 m) e em superfície. Após a formação das MPB, essas foram plantadas em Latossolo Vermelho eutroférrico, com os devidos tratamentos. Para as análises de desenvolvimento aéreo foram avaliados em seis períodos: 15, 30, 45, 60, 75, 90 dias após o plantio, a área foliar, comprimento e diâmetro de colmos e massa seca da parte aérea. A torta de filtro influenciou positivamente o desenvolvimento das mudas pré-brotadas promovendo maior área foliar e diâmetro de colmos quando aplicada em superfície. A dose 30 ton. ha-1 em superfície proporcionou produção 54% maior de massa seca de parte aérea e 56% mais massa seca de raízes em comparação ao cultivo sem sua aplicação, podendo ser utilizada para melhor desenvolvimento de mudas pré-brotadas.

The objective of this study was to evaluate changes in microbiological attributes of soils under different growing systems. Three cropping systems were evaluated (1) no-tillage system (NTS); (2) conventional tillage system (CTS); and (3) newly scarified no-tillage system (SNTS). The three systems were maintained for 20 years. In addition, a primary forest (PF) fragment was used as a reference. Soil samples were collected at depths of 0.0-0.1 m, 0.1-0.2 m, and 0.2-0.3 m. The following variables were measured: microbial biomass carbon (MBC); soil respirometry (RESP) using the fumigation and incubation method; microbial biomass nitrogen (MBN) using fumigation and extraction; metabolic quotient (qCO2) using the RESP-MBC ratio; and number of spores (NS) of mycorrhizal fungi by plate counting of spores extracted from the soil by wet sieving. Treatments were arranged in a completely randomized block design with five replicates. The different management systems affected the soil microbiota, especially in the superficial layer of 0.0-0.1 m. At a depth of 0.0-0.2 m, the PF presented significantly higher values for all analyzed attributes, except for NS. There were no significant differences in the studied characteristics between the NTS and SNTS at the three depths, indicating that scarification performed only once in the NTS was not sufficient to produce changes in soil microbiological attributes. However, the adoption of the CTS for 20 years promoted a decrease in MBC and MBN. RESP and NS were not significantly different between the cropping systems. Principal component analysis indicated a significant difference in microbiological characteristics between the PF and the areas under management. Therefore, different growing systems change the soil microbiota, and the lower the degree of tilling (NTS and SNTS), the smaller the changes in soil microbiological attributes. Soil preparation practices used in conventional tilling negatively affect soil microbial biomass, decreasing the levels of MBC and MBN.

Environmental constraints, labour shortages and the search for greater efficiency have induced the mechanisation of sugarcane harvesting, providing a large amount of straw in the system, which provides benefits to the soil, the crop and the environment. The objective of this work was to evaluate the effect of the removal of different amounts of straw from the soil surface on the development and productivity of sugarcane in eutrophic Red Latosol. The experiment was conducted in an area belonging to the Usina in Bandeirantes, PR, using a randomised block design with four replications. The effects of six treatments (0, 25%, 50%, 75%, 100% of straw and sugarcane) were evaluated after four years of cultivation on the LAI (leaf area index), tillering, diameter, length and fresh mass of the stalks, in five periods: 60, 120, 180, 240 and 370 days after harvest (DAC). The results were submitted to analysis of variance and the means compared by Tukey’s test. The straw on the soil surface provided benefits to the development and productivity of sugarcane. The management of sugarcane burning, total removal of the straw (0% of soil cover) or 75% of straw resulted in a lower IAF and stalk diameter and a 37% decrease in final yield under conditions of water deficiency. The maintenance of 50% of straw is sufficient to favour the development and to provide greater productivity of the sugarcane, as it is possible to use the 50% surplus of the field for the production of ethanol of second generation or electric energy, without damage to the productivity of the culture.

Abstract: The objective of this work was to evaluate the effect of copper use efficiency in soybean cultivars, grown on a typical Ultisol with a high organic matter content, on soil chemical properties and on plant grain yield, nutritional state, and physiological components. The experiment was carried out in greenhouse conditions, in a 5×4 factorial arrangement, with five soybean cultivars (TMG 1066RR, BRS 360RR, NA 6262RR, BMX Turbo RR, and BRS 359RR) and four Cu rates (0, 2, 4, and 8 mg kg-1). Under the studied soil conditions, the DTPA-TEA and Mehlich-1 extractants were efficient in determining available Cu in the soil. Regardless of the cultivars, Cu application increased grain yield (GY), shoot dry weight yield (SDWY), number of pods per pot, GY/SDWY ratio, photosynthetic rate, stomatal conductance, internal CO2 concentration, transpiration rate, and chlorophyll content. However, Cu use efficiency varied significantly among the different soybean genotypes. Except for Cu, soil chemical attributes and foliar and grain nutrient contents are not influenced by Cu rates nor by soybean cultivars.

O Brasil é considerado um dos maiores produtores de frutas exóticas do mundo e o cultivo da pitaya amarela (Hylocereus megalanthus) tem se destacado, apesar de estudos relacionados ao manejo dessa cultura serem incipientes O presente estudo teve por objetivo avaliar os efeitos de doses do formulado N-P2O5-K2O (NPK) na concentração 08-20-20 em mudas de pitaya amarela conduzidas em condições de casa de vegetação, contendo como substrato areia e composto orgânico (3:2, v:v). O delineamento experimental foi o de blocos ao acaso com seis tratamentos e cinco repetições. Os tratamentos consistiram na aplicação das seguintes doses do formulado NPK (08-20-20): 0, 200, 250, 300, 350 e 400 g por vaso de 5 L. As variáveis avaliadas foram taxa de enraizamento, altura, diâmetro, massa fresca (MF), massa seca (MS) da parte aérea e teor dos nutrientes dos cladódios. Apesar da aplicação de 300 g por vaso ter resultado em maior concentração de N, P, K, Ca, Mg, S, Fe e Zn nos cladódios de pitaya, a utilização de apenas adubo orgânico e areia mostrou-se suficiente para o incremento da MS e MF dos cladódios.

Some silicate rocks are a rich source of potassium (K), with the possibility for use in agriculture. The present study aimed to evaluate the agronomic efficiency index (AEI) of nepheline syenite (NS) and phonolite (PN) rocks in comparison with potassium chloride (KCl) as a K source in maize production. An experiment was conducted in a greenhouse in Ilha Solteira, São Paulo, Brazil. A maize hybrid was grown in 8 L pots filled with 6 kg of soil with a low K concentration and contrasting physical attributes (medium and sandy texture). A completely randomized design in a 3 × 6 factorial scheme was used, consisting of three K sources (NS, PN, and KCl) and six rates (0, 50, 100, 150, 200, and 400 mg kg−1) with four replications. All plants were harvested 45 days after emergence to evaluate biomass production, macronutrient (N, P, K, Ca, Mg, and S) concentration and uptake, stem diameter, and leaf chlorophyll index. After crop harvest, soil was collected for further chemical evaluation, which included organic matter (OM), pH, cation exchange capacity (CEC), H+Al, Al, sum of bases (SB), base saturation (BS), P, K, Ca, Mg, and S. In addition, AEI of NS and PN were also verified in relation to KCl. The application of NS and PN had a similar effect on soil chemical attributes (MO, pH, SB, CEC, and BS) as well as on the concentrations of K, Ca, Mg, and S, in both soils. The increase in NS and PN rates provided linear growth of shoot dry matter. Leaf macronutrient concentrations were similar for NS and PN compared to KCl. All three K sources (NS, PN, and KCl) increased K accumulation in maize plants. Maize treated with KCl had the largest AEI, followed by PN and NS. However, the results indicated similar AEI with both rocks as a K source for maize, especially with application of the highest K rates. This research demonstrated the efficiency of NS and PN as alternative K sources for maize.

The objective of this work was to evaluate the effects of the application of phosphogypsum and vinasse on soil chemical properties and productivity and nutritional characteristics of alfalfa (Medicago sativa). The experiment was conducted in a randomized block design, using a 3×5 factorial arrangement, with three vinasse rates (0, 150 and 300 m3 ha-1) and five phosphogypsum rates (0, 3, 6, 9 and 12 Mg ha-1). The alfalfa chemical composition and shoot dry matter (SDW) and soil chemical properties (in the layers 0.0-0.2 and 0.21-0.4 m) were evaluated. The vinasse rates increased the soil potassium contents, while the phosphogypsum rates promoted linear increases in soil calcium and sulfur contents. The base saturation was increased and the magnesium content showed a quadratic response on the layer 0.21-0.4 m with the increase in phosphogypsum rates. The calcium, magnesium and phosphorus contents in the alfalfa leaves were lower with vinasse application. The phosphogypsum rates promoted linear increases in alfalfa SDW. Vinasse rated 150 m3 ha-1 was been enough to SDW increase. Calcium and magnesium contents in the leaves fitted a quadratic model, with maximum calcium content in the phosphogypsum rate of 9.5 Mg ha-1 and the minimum magnesium content in the phosphogypsum rate of 8.7 Mg ha-1. The leaf sulfur contents in all vinasse rates and leaf potassium contents in the highest vinasse rate showed maximum accumulation at near 9 Mg ha-1 of phosphogypsum.

Resumo O objetivo deste trabalho foi quantificar os efeitos da substituição da floresta primária por seringal (Hevea spp.), quanto aos atributos físicos, químicos e biológicos de um Latossolo Amarelo distrófico na Amazônia Central. Amostras de solo foram coletadas na profundidade de 0,0-0,1 m, em área de floresta primária e em seringais de 2,0 ha com idades de plantio de 6, 16, 18, 19, 20 e 45 anos. O reflorestamento das áreas por seringais não minimiza os efeitos negativos da retirada da floresta primária, com aumento do quociente metabólico e redução nos teores de carbono orgânico, carbono da biomassa microbiana (CBM), nitrogênio da biomassa microbiana (NBM), porosidade, enzimas (arilsulfatase, β-glucosidase e β-galactosidase) e substâncias húmicas (ácidos húmicos e fúlvicos e humina) do solo. O CBM e o NBM variaram de 291,97 a 615,27 µg g-1 e de 65,76 a 98,58 µg g-1, e mostram-se como os atributos mais sensíveis às alterações decorrentes da substituição da floresta primária por seringais.

A sigatoka-negra (Mycosphaerella fijiensis Morelet) é a principal doença da bananeira e pode causar 100% de perdas na produção. O conhecimento do progresso da doença é importante para definir as estratégias de controle a serem adotadas. O objetivo deste trabalho foi estudar o comportamento da sigatoka-negra em bananeiras na região Centro-Sul do Estado do Mato Grosso. O experimento foi realizado com as cultivares ‘Maçã’, ‘Farta Velhaco’ e ‘Grande Naine’. A severidade da doença foi avaliada a cada 15 dias, em todas as folhas de 10 plantas de cada cultivar. A precipitação pluvial, temperatura e a umidade relativa do ar (UR%) foram registradas diariamente. Os dados da severidade da doença na folha número 8, número de folhas viáveis e a folha mais jovem com sintomas foram correlacionados com os dados climáticos. Constatou-se que as condições climáticas da região favoreceu a ocorrência da doença durante o ano todo. Dessa forma, o plantio de cultivares resistentes é a medida de controle mais indicada para a região.

Naturally infertile soils require large amounts of mineral fertilizers to obtain the desired crop yield. In the Cerrado region of Brazil, there is a need to investigate the potential of organic fertilizers to sustainably increase crop productivity and food security. A field study was conducted over two experimental seasons to evaluate the agronomic effectiveness of composted sewage sludge (CSS) as a fertilizer for soybean cultivation in infertile tropical soils. A 4 × 2 + 2 factorial randomized complete block design was applied with the following treatments: (i) CSS: 5.0, 7.5, 10.0, and 12.5 Mg ha−1 on a wet basis applied according to two different methods: whole area (WA) or between rows (BR); (ii) comparison with two alternative treatments: a control with no CSS and mineral fertilizer application, and an area treated with conventional fertilizers only. All the treatments were compared in terms of micronutrient concentrations in surface soil and plant leaves, plant development, crop productivity, and yield. Bi- (ANOVA, correlation matrix, and polynomial regression analysis) and multivariate (PCA, principal factor analysis) statistics were applied to determine statistical differences and relationships/observed variability among the treatments. Results showed that at higher CSS-WA rates: (i) soil and leaf micronutrient concentrations increased; (ii) there was an increase in soybean yield by 12 and 20%, respectively, as compared to control and conventional fertilization; (iii) soybean yield was 67% higher than the mean soybean yields for Brazil. Research outcomes confirm the benefits of CSS application on infertile agricultural soils in the Cerrado region, representing a strong alternative source of micronutrients in the CSS with respect to conventional fertilizers.

O objetivo deste trabalho foi avaliar alterações nos atributos microbiológicos do solo em diferentes sistemas de manejo. Avaliou-se três tipos de manejo de solo (1) sistema de plantio direto -SPD; (2) plantio convencional - PC, ambos estabelecidos a 20 anos e (3) sistema de plantio direto de 20 anos recém escarificado - SPDE. Além desses, um fragmento de floresta primária (FP) foi usado como referência. Amostras de solo foram coletadas nas profundidades de 0,0 - 0,1; 0,1 - 0,2 e 0,2 - 0,3 m e determinados o carbono da biomassa microbiana (CBM) e a respirometria do solo (RESP) pelo método da fumigação e incubação, o nitrogênio da biomassa microbiana (NBM) determinado por fumigação e extração, o quociente metabólico (qCO2) pela razão entre RESP/CBM, e o número de esporos de fungos micorrízicos (nESP) por contagem em placa sob microscópio dos esporos extraídos do solo por peneiramento úmido. Os dados foram analisados como delineamento inteiramente ao acaso com cinco repetições. Os diferentes manejos influenciaram a microbiota do solo, destacadamente na camada superficial de solo 0,0 - 0,1 m. Na profundidade de 0,0 - 0,2 m a FP observou-se valores significativamente maiores para todos os atributos analisados, exceto nESP. O SPD e SPDE não diferiram nas profundidades para nenhum dos atributos, mostrando que a escarificação realizada apenas uma vez no SPD, não foi suficiente para produzir alterações sobre os atributos microbiológicos do solo. Entretanto, o manejo do solo em PC por 20 anos promoveu reduções no CBM e NBM. A RESP não se diferenciou entre os manejos, assim como o nESP. Na análise de componentes principais houve evidente distância, em termos de atributos microbiológicos, entre a FP e as áreas sob manejo. Conclui-se que os diferentes manejos de solo alteram a microbiota, sendo que, quanto menor a intensidade do manejo (SPD e SPDE) menores são as alterações nos atributos microbiológicos do solo. As práticas de preparo do solo usadas no plantio convencional alteram negativamente a biomassa microbiana do solo, causando reduções no CBM e NBM.

As restrições ambientais, a falta de mão-de-obra e a busca por maior eficiência induzem a mecanização da colheita de cana-de-açúcar, disponibilizando grande quantidade de palhada no sistema, que proporciona benefícios ao solo, à cultura e ao meio ambiente. O objetivo desse trabalho foi avaliar o efeito da retirada de diferentes quantidades de palhada da superfície do solo sobre o desenvolvimento e a produtividade da cana-de-açúcar em Latossolo Vermelho eutroférrico. O experimento foi instalado em área pertencente a Usina em Bandeirantes, PR, utilizando delineamento em blocos casualizados com quatro repetições. Foram avaliados os efeitos de seis tratamentos (0, 25%, 50%, 75%, 100% de palhada e cana-queimada), após quatro anos de cultivo, sobre o IAF (Índice de área foliar), perfilhamento, diâmetro, comprimento médio e massa fresca dos colmos, em cinco períodos: 60, 120, 180, 240 e 370 dias após a colheita (DAC). Os resultados foram submetidos à análise de variância e as médias comparadas pelo teste Tukey. A palhada sobre a superfície do solo proporcionou benefícios ao desenvolvimento e a produtividade da cana-de-açúcar. Os manejos queima da cana-de-açúcar, retirada total da palhada (0% de cobertura do solo) ou de 75% de palhada resultaram em menor índice de área foliar, diâmetro de colmos e diminuição de 37% na produtividade final, em condições de deficiência hídrica. A manutenção de 50% de palhada é suficiente para favorecer o desenvolvimento e proporcionar maior produtividade da cana-de-açúcar, sendo possível utilizar os 50% excedente do campo para produção de etanol de segunda geração ou energia elétrica, sem prejuízos à produtividade da cultura.

The guava tree (Psidium guajava L.), considered a rustic plant, can be found growing naturally in low-fertility soils. However, when commercially cultivated it needs considerable amounts of fertilizers and soil correctives to attain good yields. These special measures for cultivation start with choice of a suitable substrate to grow good-quality seedlings, allowing them to reach their full productive potential. The aim of this work was to study the effect of different substrates (S1 – soil, S2 – vermiculite+soil+fine sand, S3 – cattle manure+soil+fine sand, S4 – commercial substrate+soil+fine sand, S5 – urban compost+soil+fine sand, S6 – sewage sludge+soil+fine sand, S7 – earthworm compost+soil+fine sand, S8 – chopped sugarcane bagasse+soil+fine sand, and S9 – sugarcane filter cake+soil+fine sand) in completely randomized design with four replicates on the development and nutritional state of guava seedlings. The result showed that the best substrates were vermiculite+soil+fine sand; earthworm compost+soil+fine sand; sugarcane bagasse+soil+fine sand, and filter cake+soil+fine sand. The use of sewage sludge and urban trash compost should be further studied for the composition of substrates.

O objetivo deste trabalho foi avaliar o desempenho de 12 combinações de três clones de painel (PB 311, PB 314 e RRIM 600) com quatro clones de copa (F 4512, MDF 180, IAN 6158 e IAN 6543) de seringueira cultivados no sudoeste do Estado do Mato Grosso. Utilizou-se o delineamento experimental de blocos ao acaso, com quatro repetições. Foram avaliados: produção de borracha seca, percentagem de plantas aptas à sangria, secamento de painel, estado nutricional, teor de borracha seca, plasticidade Wallace (P0 e P30), índice de retenção de plasticidade e viscosidade Mooney. As combinações das copas IAN 6543 e MDF 180 com os painéis PB 311, RRIM 600 e PB 314 apresentaram estado nutricional adequado, com produtividade de borracha seca acima de 1,41 Mg ha-1 por ano. O clone de copa IAN 6158 propiciou, em oito anos, as maiores quantidades de plantas aptas à sangria. As combinações painel/copa apresentaram baixa incidência de secamento de painel, exceto PB 311 x IAN 6158. As borrachas das 12 combinações painel/copa apresentam boa resistência à degradação térmica e alta retenção de plasticidade.

A fenologia foliar tem sido utilizada como uma característica importante na seleção dos clones de Hevea spp., enquanto o teor de nutrientes na serapilheira é um bom indicador da ciclagem de nutrientes. O objetivo deste trabalho foi verificar o efeito da periodicidade de emissão de fluxos foliares na floração de copa de Hevea pauciflora, estado nutricional e qualidade da serapilheira. Foram avaliadas 15 plantas de 10 anos de idade dos clones de copa CNS G 112, CNS G 124 e CBA 2. Nas condições edafoclimáticas da Amazônia tropical úmida, a emissão de folhas e de floração de H. pauciflora ocorre com maior intensidade no segundo semestre (início do período chuvoso). A H. pauciflora apresenta maior acúmulo de serapilheira que a floresta primária e os teores foliares de 22,18 g kg-1 de N, 1,47 g kg-1 de P, 5,77 g kg-1 de K, 3,79 g kg-1 de Ca, 2,09 g kg-1 de Mg, 16,15 mg kg-1 de B, 6,14 mg kg-1 de Cu, 53,87 mg kg-1 de Fe, 66,20 mg kg-1 de Mn e 48,44 mg kg-1 de Zn podem ser utilizados como referência para essa espécie de seringueira.The leaf phenology has been used as an important characteristic in the selection of Hevea spp. clones, while the nutrient content in litter is a good indicator of nutrient cycling. The objective of this study was to verify the effect of frequency of emission of fluxes of leaves and flowers in crown of Hevea pauciflora, nutritional status and quality of litter. Fifteen plants of ten-year-old of each clones (CNS G 112, CNS G 124 and CBA 2) were evaluated. In tropical Amazonia edaphoclimatic conditions, the leaf emergence and flowering of H. pauciflora occurs with higher intensity in the second semester (beginning of rainy season). The H. pauciflora has higher quantity of litter than the primary forest, and the foliar concentrations of 22.18 g kg-1 of N, 1.47 g kg-1 of P, 5.77 g kg-1 of K, 3.79 g kg-1 de Ca, 2.09 g kg-1 of Mg, 16.15 mg kg-1 of B, 6.14 mg kg-1 of Cu, 53.87 mg kg-1 of Fe, 66.20 mg kg-1 of Mn e 48.44 mg kg-1 of Zn can be utilized as reference for this specie of rubber tree.

The objective of this work was to assess the possible transport of cyanogenic glycosides from leaves of rubber tree crown clones (Hevea spp.) resistant to South American leaf blight to the trunk of the panel clones in which they are grafted. The cyanogenic potential (HCNp) of the crown clones was determined in the trunk bark, at different distances from the cambium, and its gradient was evaluated along the trunk. The correlation between the HCNp of the crown leaves and that of the trunk bark was also evaluated. HCNp determined in leaves showed a wide range variation in the species studied as crown clones, with the lowest values registered in H. nitida clones, and the highest ones in H. rigidifolia. In the trunk bark, the tissue layer nearer the cambium showed higher HCNp values. A positive basipetal gradient was observed along the trunk, i.e., there was an increase in HCNp from the apex toward the base. Although the grafted crowns influence the cyanogenic potential of the trunk bark of panel clones, the absence of correlation between the HCNp of the leaves and trunk bark indicates that the crown is not the main source of the cyanogenic glycosides found in the trunk.

The objective of this work was to assess the performance of panel clones under crowns resistant to South American leaf blight (Microcyclus ulei). The experiment was carried out with 18 panel clones crown-budded with Hevea pauciflora x H. guianensis, in a Xanthic Ferralsol (Oxisol) in Manaus, AM, Brazil. The following parameters were evaluated: dry rubber yield, plant nutritional status, and anatomical and physiological characteristics of the latex vessels. In the first three years of evaluation, the panel clones IAN 2878, IAN 2903, CNS AM 7905, CNS AM 7905 P1, and PB 28/59 showed the highest dry rubber yield potential, while the clones IAN 6158, IAN 6590, and IAN 6515 should not be recommended for crown budding. Higher potassium and copper foliar content in panel clones were associated to an increase in dry rubber yield. The simultaneous evaluation of anatomical and physiological characteristics of latex is fundamental for the selection of panel clones in the Amazon region. Crown budding is an efficient technology for South American leaf blight management in endemic regions.

Most studies in the literature regarding the uptake of micronutrients [zinc (Zn), manganese (Mn), iron (Fe), copper (Cu) and boron (B) accumulation] by sunflower are old. For this reason, this work is aimed to establish curves of sunflower micronutrient accumulation in tropical edaphoclimatic conditions. The experiment was conducted in field on Rhodic Eutrudox, located at the experimental farm of Embrapa Soja in Londrina-PR, using the commercial hybrid BRS 191. The experimental design was completely randomized, with four replicates. The experimental units consisted of 14 lines with a spacing of 0.70 meter between lines and 25.0 meters in length, with final density of 42,858 plants per hectare. Plants samples were collected every 14 days after emergence. After each collection, plants were divided into petiole, leaf, stem, capitulum and achenes. They were dried until reaching constant weight. Then, dry matter was weighed and the concentrations of Zn, Mn, Fe, Cu, and B were determined in the vegetal tissue. Micronutrient uptake occurred faster in the phase initiated 42 days after emergence (DAE). Iron was the most absorbed micronutrient, accumulating higher amounts in the achenes as well as in relation to the total absorbed. Fe, Mn, Zn, B and Cu concentrations were 38.06, 19.68, 9.20, 8,62 and 4.27 mg plant-1, respectively.Devido ao fato de a maioria dos trabalhos encontrados na literatura a respeito do acúmulo dos micronutrientes [zinco (Zn), manganês (Mn), ferro (Fe), cobre (Cu) e boro (B)] no girassol serem antigos, objetiva-se, com este trabalho estabelecer curvas de acúmulo de micronutrientes em um híbrido de girassol na condição edafoclimática dos trópicos. O experimento foi instalado no campo sobre Latossolo Vermelho distroférrico de textura argilosa, localizado na fazenda experimental da Embrapa Soja, em Londrina-PR, utilizando o híbrido comercial BRS 191. O delineamento experimental utilizado foi o inteiramente casualizado, com quatro repetições. As unidades experimentais foram constituídas de 14 linhas, com espaçamento de 0,70 m entre linhas e 25 m de comprimento, com densidade final de 42.858 plantas ha-1. As amostras das plantas foram coletadas em intervalos de 14 dias após a emergência. Após cada coleta, dividiram-se as plantas em pecíolo, folha, caule, capítulo e aquênios, sendo que as mesmas foram secas até peso constante, quando foram tomados os pesos da matéria seca e determinados os teores de Zn, Mn, Fe, Cu e B no tecido vegetal. A absorção de micronutrientes ocorreu em maior velocidade a partir dos 42 dias após a emergência (DAE). O Fe foi o micronutriente mais absorvido, acumulando maior quantidade tanto nos aquênios como em relação ao total absorvido. O acúmulo total de Fe, Mn, Zn, B e Cu foram 38,06, 19,68, 9,20, 8,62 e 4,27 mg planta-1, respectivamente.

A utilização de calcário em plantio direto é um dos problemas na adoção desse método de manejo do solo. O trabalho teve por objetivo avaliar as alterações nas propriedades químicas do solo cultivado nos sistemas de plantio convencional (SCC) e plantio direto (SPD),em função da granulometria e de doses de calcário dolomítico aplicado em superfície. Os experimentos foram realizados por três anos agrícolas em Latossolo Vermelho distrófico, em área de pastagem de Urochloa decumbens, com cultivo de milho em sucessão com aveia preta e triticale. O delineamento experimental utilizado foi os blocos casualizados em parcelas sub-subdivididas, com quatro repetições. Foram realizadas análises químicas (pH, Ca, Mg, H+Al e saturação porbases) do solo coletado nas camadas de 0-5 cm, 5-10 cm, 10-20 cm e 20-40 cm aos 12, 24 e 36 meses após a implantação dos experimentos. Os resultados evidenciaram alterações nas propriedades químicas do solo, com aumento significativo do pH, Ca e Mg trocáveis, saturaçãopor bases e redução da acidez potencial até 10 cm de profundidade no SPD, com diferenças significativas em relação ao SCC. Nas profundidades de 10-20 cm e 20-40 cm, houve inversão, e os efeitos na neutralização da acidez do solo foram mais pronunciados no SCCque no SPD. A utilização de calcário com PRNT de 95% proporcionou melhor neutralização da acidez do solo até 10 cm de profundidade. A aplicação em superfície do corretivo da acidez antes da implantação do SPD não foi suficiente para elevar a saturação por bases em nível almejado para a cultura do milho.The use of limestone in no-tillage system usually causes great problems in soil management. The objective of this work was to evaluate the changes in the chemical properties of the soil under no-tillage (NTS) and conventional tillage system (CTS) due to granulometric fraction [Effective Calcium Carbonate (ECC) = 95% and 56%] and three rates (95% ECC = 1.2, 2.4 and 3.6 t ha-1 and 56% ECC = 2, 4 and 6 t ha-1) of dolomite lime applied in surface two months prior to system implantation. The experiment was carried out in a split-plot design with four replications in a dystrophic Red Latosol (Oxisol) during three years, in area of pasture of Urochloa decumbens using a succession of corn and black oat. The soil chemical characteristics (pH, Ca, Mg, H+Al and base saturation) were analyzed in 12, 24 and 36 months before each sowing in the depths 0-5 cm, 5-10 cm, 10-20 cm and 20-40 cm. The results evidenced alterations in soilchemical properties with pH increase, exchangeable calcium and magnesium, base saturation, and reduction of potential acidity up to 10 cm of depth in NTS, with significant differences in relation to CTS. In the depths of 10-20 cm and 20-40 cm, there was an inversion, and the effects in the neutralization of soil acidity were more pronounced in the CTS than the NTS. The application of lime with 95% ECC showed better neutralization of soil acidity up to 10 cm ofdepth. The use of lime with 95% ECC provided better neutralization of the acidity of the soil up to 10 cm of depth. The corrective application in surface before the implantation of SPD was enough to elevate the base saturation for levels adapted for the corn yield.

In the Amazon region, there is no information on the fertilization of banana plants with boron (B). Besides this, the extractant (hot water) currently used to test B concentrations has many limitations. The aim of this work was to study the effect of B on the fruit yield and quality of banana plants of the Cavendish (AAA) sub-group, grown in dystrophic Yellow Latosol (Oxisol or Xanthic Ferralsol), in the Amazonas State, Brazil. The experimental design was completely randomized split plot in a 4 x 2 factorial scheme, composed of four B rates (0, 4, 8 and 12 kg ha-1) and two harvest cycles (sub-treatments), with four replicates. The B availability in the soil was determined by three extractants: Mehlich 3, hot water and KCl 1.0 mol L-1. The application of B influences the fruit yield, pulp/peel ratio, pulp resistance and B content in the leaves and fruits. The KCl 1.0 mol L-1 extractant was similar to the hot water in the evaluation of available B. To obtain maximum yield, it is necessary to apply 4.1 and 6.1 kg ha-1 of B in the first and second cycles, respectively.Na Amazônia não existem informações sobre adubação com boro (B) na bananeira, além disso, o extrator água quente, que é atualmente o mais utilizado, apresenta inúmeras limitações. O objetivo deste trabalho foi estudar o efeito do B sobre a produção e qualidade dos frutos da bananeira do subgrupo Cavendish (AAA), cultivada em Latossolo Amarelo distrófico, no Estado do Amazonas, Brasil. O delineamento experimental utilizado foi o inteiramente casualizado em parcela subdividida em esquema fatorial 4 x 2, constituído por quatro doses de B (0, 4, 8 e 12 kg ha-1) e dois ciclos de colheita - sub-parcelas (primeiro e segundo ciclo), com quatro repetições. A disponibilidade de B no solo foi determinada pelos extratores Mehlich 3, água quente e KCl 1,0 mol L-1. A aplicação de B influenciou a produção, relação polpa e casca, resistência da polpa e o teor de B nas folhas e nos frutos. O extrator KCl 1,0 mol L-1 foi semelhante ao água quente na avaliação do B disponível. Para obtenção do máximo potencial de produção é necessário aplicar 4,1 e 6,1 kg ha-1 de B no primeiro e no segundo ciclo, respectivamente.

Foram estimados os coeficientes de repetibilidade das características de produção de matéria seca (PMS), altura das plantas no momento do corte (APC), tolerância a doenças (TD) e altura no florescimento (AF), em genótipos de alfafa. As características foram avaliadas em 92 genótipos nos anos 2004 e 2005, durante 11 cortes, feitos nos períodos das águas (novembro a março, cinco cortes) e da seca (abril a setembro, seis cortes). O experimento foi conduzido em blocos ao acaso, com duas repetições. As estimativas dos coeficientes de repetibilidade foram obtidas por diferentes métodos de análises. Também realizou-se estudo da estabilização genotípica. Todas as análises estatísticas foram realizadas com auxílio do aplicativo computacional GENES. No período da seca, apenas dois cortes foram suficientes para se ter certeza de 85% na previsão do valor real para a PMS, sendo necessários cinco cortes para se obter a mesma confiabilidade nesta característica no período das águas. De maneira geral, no período das águas foi necessário maior número de avaliações para obter igual veracidade da comprovação genotípica. Pela estabilização genotípica, observouse aumento da confiabilidade com a eliminação de alguns cortes, chegando a até 97% com apenas três cortes, excluindose dois cortes iniciais e um final. As variáveis PMS e APC, no período das águas, apresentaram maiores estimativas do coeficiente de repetibilidade do que TD e AF.

The objective of this work was to evaluate the effects of cattle manure, reactive natural phosphate and biotite schist on the soil fertility, yield and nutritional status of Megathyrsus spp. cv. Massai. The experiment was conducted under field conditions, in a dystrophic Red Yellow Latosol (Oxisol). It was used a randomized block experimental design with the following treatments: three natural reactive rock phosphate from Algeria (Djebel-Onk) doses (0, 100 and 200 kg ha-1 of P2O5), three biotite schist doses (0, 150 and 300 kg ha-1 of K2O) and three cattle manure doses (0, 20 and 40 t ha-1). The application of natural phosphate increased dry matter yield, however, application of cattle manure and biotite schist did not influence this variable. Foliar levels of nitrogen, potassium and magnesium (cattle manure), phosphorous and boron (natural rock phosphate) and potassium (biotite schist) were influenced by the applied fertilizer doses. Only the levels of phosphorous in the soil and in the plant and levels of magnesium and boron in the plant show interaction with dry matter yield of Massai cultivar.Objetivou-se avaliar os efeitos de esterco bovino, fosfato natural reativo e biotita xisto sobre a fertilidade do solo, a produção e o estado nutricional de Megathyrsus spp. cv. Massai. O experimento foi realizado em condições de campo, em Latossolo Vermelho Amarelo distrófico (Oxisol). O delineamento experimental utilizado foi o de blocos casualizados, com os seguintes tratamentos: três doses de fosfato natural reativo da Argélia, Djebel-Onk (0, 100 e 200 kg ha-1 de P2O5), três doses de biotita xisto (0, 150 e 300 kg ha-1 de K2O) e três doses de esterco bovino (0, 20 e 40 t ha-1). A aplicação de fosfato natural aumentou a produção de matéria seca, enquanto as aplicações de esterco bovino e a biotita xisto não influenciaram esta variável. Os teores de nitrogênio, potássio e magnésio (esterco bovino), fósforo e boro (fosfato natural) e potássio (biotita xisto) nas folhas foram influenciados pelas doses de fertilizante aplicadas. Somente os níveis de fósforo no solo e na planta e os de magnésio e boro na planta apresentam interação com a produção de matéria seca da cultivar Massai.

Alfalfa is an important forage crop with high nutritive value, although highly susceptible to soil acidity. Liming is one of the most efficient and prevailing practices to correct soil acidity and improve alfalfa yield. The objective of this study was to evaluate response to liming of alfalfa grown in a greenhouse on a Typic Quartzipsamment soil. The treatments consisted of four lime rates (0, 3.8, 6.6 and 10.3 Mg ha-1) and two cuts. Alfalfa dry matter increased quadratically with increasing lime rates. In general, dry matter yield was maximized by a lime rate of 8.0 Mg ha-1. Except for the control, the dry matter nutrient contents in the treatments were adequate. The positive linear correlation between root and nodule dry matter with lime rates indicated improvement of these plant traits with decreasing soil acidity. The soil acidity indices pH, base saturation, Ca2+ concentration, Mg2+ concentration, and H + Al were relevant factors in the assessment of alfalfa yield. The magnitude of influence of these soil acidity indices on yield as determined by the coefficient of determination (R²) varied and decreased in the order: base saturation, H + Al, pH, Ca and Mg concentrations. Optimum values of selected soil chemical properties were defined for maximum shoot dry matter; these values can serve as a guideline for alfalfa liming to improve the yield of this forage on acid soils.A alfafa é uma importante forrageira com alto valor nutritivo, porém é altamente suscetível à acidez do solo. A calagem é uma das mais eficientes práticas para corrigir esse problema e melhorar a produtividade da alfafa. O objetivo deste trabalho foi avaliar a resposta à calagem da alfafa cultivada em Neossolo Quartzarênico em casa de vegetação. Os tratamentos consistiram de quatro doses de calcário (0; 3,8; 6,6 e 10,3 Mg ha-1) e duas épocas de corte. A produção de matéria seca foi significativamente aumentada com a adição de calcário, com o máximo rendimento estimado obtido com a adição de 8,0 Mg ha-1. Exceto na testemunha, o teor de nutrientes na matéria seca foi adequado. A matéria seca de raízes e de nódulos foi significativamente aumentada com a aplicação de calcário. Os índices de acidez do solo, como pH, saturação por bases, concentração de Ca2+ e de Mg2+ e H + Al, foram importantes na avaliação do rendimento da alfafa. Magnitudes de influência da acidez do solo desses índices no rendimento variaram, conforme determinado pelo coeficiente de determinação (R²) obedeceram a seguinte ordem decrescente: saturação por bases, H + Al, pH, concentração de Ca2+ e de Mg2+ . Os valores considerados ótimos das propriedades químicas do solo selecionados para obtenção da máxima produção estimada podem servir como referência e melhorar o rendimento de culturas forrageiras em solos ácidos.

A colonização radicular com fungos micorrízicos arbusculares (FMA) pode aumentar a eficiência no crescimento e absorção de nutrientes pelas plantas. Com o objetivo de verificar esse efeito, foram avaliados o grau de colonização em seringais adultos cultivados em Latossolo Amarelo distrófico e a eficiência de seis FMAs na colonização, crescimento e estado nutricional de mudas de seringueira com três e seis meses de transplantio. Os resultados indicaram baixo grau de colonização micorrízica e número de esporos em seringal adulto. Seis meses depois do transplantio das mudas de seringueira foram suficientes para ocorrer colonização de FMAs detectável. Não houve aumento no incremento em altura, diâmetro e emissão de folhas, independentemente do inóculo utilizado. Os teores foliares de nutrientes (N, P, K, Ca, Mg, Cu, Fe, Mn e Zn) também não foram influenciados pelo número de esporos e grau de colonização, havendo diferenças apenas em função da idade das plantas.The infection roots with arbuscular mycorrhizal fungi (AMF) can increase the efficiency in growth and nutrients uptake of plants. With the objective to verify this effect, the degree of colonization in rubber tree plantation cultivated in a Xanthic Ferralsol (dystrophic Yellow Latosol) and the efficiency of six AMF in colonization, growth and nutritional status of rubber tree seedlings were evaluated, with three and six months of transplanting. The results showed a low level of mycorrhizal infection and number of spores in adult rubber tree. Six months of transplanting of rubber tree seedlings were sufficient detectable AMFs infection. There was no increase in height, diameter and number of leaves. The foliar nutrients concentration (N, P, K, Ca, Mg, Cu, Fe, Mn and Zn) were also not influenced by the number of spores and infection degree, with only differences by age of the plants (three and six months of transplanting).

Neste trabalho, objetivou-se avaliar a eficiência de seis extratores de B e o efeito de doses sobre os teores de B e produção de matéria seca da soja cultivada em condições de casa de vegetação com LATOSSOLO VERMELHO Eutroférrico coletados em Mauá da Serra e Londrina (PR) e NEOSSOLO QUARTZARÊNICO Órtico de Alto Garças (MT). O delineamento experimental utilizado foi o inteiramente casualizado, constituído por seis doses de B (0, 0,25, 0,5, 1, 2 e 4 kg ha-1), com três repetições. O B disponível foi determinado por seis soluções extratoras: Mehlich 1, Mehlich 3, água quente, HCl 0,05 mol L-1, Ca(H2PO4)2.H2 O 0,01 mol L-1 e KCl 1,0 mol L-1. Nas condições estudadas, os resultados mostraram que o B extraído por água quente acarretou as melhores correlações com a produção de matéria seca e conteúdo de B na planta, enquanto o extrator KCl 1,0 mol L-1 foi o mais eficiente na determinação do teor de B no tecido vegetal. Altas concentrações de B diminuíram a eficiência do extrator água quente em determinar o B disponível do solo. As maiores correlações foram obtidas entre os extratores Mehlich 1 e Ca(H2PO4)2.H2 O 0,01 mol L-1, KCl 1,0 mol L-1 e HCl 0,05 mol L-1, KCl 1,0 mol L-1 e Ca(H2PO4)2.H2 O 0,01 mol L-1 e água quente e Ca(H2PO4)2.H2 O 0,01 mol L-1.The objective of this work was to evaluate the efficiency of six extractants and the effect of boron concentration and dry matter yield, cultivated in greenhouse conditions with two Rhodic Hapludox in Mauá da Serra and Londrina, in the State of Paraná, and one Ustoxix Quatzipsamment in Alto Garças, State of Mato Grosso, Brazil. The experiment was conducted in a completely randomized design with six boron rates (0, 0.25, 0.5, 1, 2 and 4 kg ha-1), and three replicates. The available boron was determined with six extractant solutions: Mehlich 1, Mehlich 3, hot water, HCl 0.05 mol L-1, Ca(H2PO4)2.H2 O 0.01 mol L-1 and KCl 1.0 mol L-1. The results showed that the B extracted by hot water had the best correlation with the dry matter yield and B content in the plant, whereas the KCl 1.0 mol L-1 was the most efficient in the determination of B level in dry matter. High concentrations of B diminished the efficiency of the hot water extractant in determining the B available in soil. The highest correlations were obtained between the extractant Mehlich 1 and Ca(H2PO4)2.H2 O 0.01 mol L-1, KCl 1.0 mol L-1 and HCl 0.05 mol L-1, KCl 1.0 mol L-1 and Ca(H2PO4 )2.H2O 0.01 mol L-1, and hot water and Ca(H2PO4)2.H2 O 0.01 mol L-1.

Este estudo foi desenvolvido objetivando comparar diferentes critérios de seleção, indicar o método de seleção que propicia maiores estimativas de ganho genético e identificar genótipos superiores de alfafa quanto a características produtivas, morfológicas e bromatológicas. Foram avaliadas a produção de matéria seca, altura de planta, tolerância a doenças, aceitação fenotípica pelos animais, proteína bruta, digestibilidade in vitro da matéria seca, fibra em detergente neutro e relação caule/folha de 92 acessos provenientes do INTA-Argentina, tendo como testemunha o Crioula. Os Índices de Mulamba & Mock, distância do genótipo ao ideótipo e Elston foram os mais adequados a esse tipo de estudo. Os genótipos Sequel, CUF 101, Siriver 2, Florida 77, Diamond, Sequel 2, LE N 2, Medina, Kern, Rio Grande, DK 166, DK 181, Perla SP INTA, WL 516, Rocio, LE Semit 711 e LE N 3 foram os indicados à seleção pelos maiores índices de Mulamba e Mock, distância do genótipo ao ideótipo e índice de Elston.

A bananeira demanda grandes quantidades de corretivos e fertilizantes para manter suas exigências nutricionais e obter alta produtividade, porém grande porcentagem aplicada não é disponibilizada, sendo perdida, principalmente, por fixação, lixiviação e volatilização. O objetivo deste trabalho foi verificar a taxa de remobilização e repartição de nutrientes na bananeira cultivar Thap Maeo, cultivada na Amazônia Ocidental. Os resultados mostraram que as maiores proporções de K, Na, Mg, S, B, Cu, Fe e Zn se encontram contidas no pseudocaule. Os restos florais da bananeira constituem forte dreno temporário de nutrientes. A biomassa proveniente dos restos de cultura representa fonte significativa de nutrientes para as plantas. O N e K apresentam o maior índice relativo de remobilização, sendo o inverso observado com o Mn e Fe.The banana tree demands large quantities of fertilizers to maintain its nutritional requirements and achieve high productivity, but large percentage applied are not available, since it gets lost mainly by fixation, leaching and volatilization. The objective of this study was to evaluate the rate of remobilization and repartition of nutrients in banana tree, cultivar Thap Maeo, cultivated in the Western Amazon. The results showed that the highest proportion of K, Na, Mg, S, B, Cu, Fe and Zn was found in the pseudostem. The remaining flowers represent a strong drain of nutrients. The biomass that comes from the culture residues represents a significant source of nutrients. The nutrient remobilization index was higher with N and K. The inverse was observed with Fe and Mn.

O objetivo deste trabalho foi avaliar a disponibilidade de B, Cu, Fe, Mn e Zn em solos com horizonte A antrópico (Terra Preta do Índio - TPI) da Amazônia Central com as soluções extratoras Mehlich 1 (M1), Mehlich 3 (M3) e DTPA-TEA. Foram utilizadas dezesseis amostras de terra preta de diferentes profundidades provenientes de dez sítios arqueológicos e de cinco classes de solos representativas da região (Espodossolo, Neossolo, Latossolo, Argissolo e Cambissolo). Na Terra Preta de Índio, o extrator DTPA-TEA extraiu as maiores quantidades de Cu e Fe disponível, enquanto o Mehlich 1 extraiu mais Mn e Zn. Nas condições edafoclimáticas estudadas, o extrator Mehlich 1 mostrou, na média, maior sensibilidade quando comparado com os extratores Mehlich 3 e o DTPA-TEA. Os melhores coeficientes de correlação entre os extratores foram obtidos com: Cu disponível (Mehlich 3 e DTPA-TEA), Fe disponível (Mehlich 1 e DTPATEA), Mn e Zn disponível (Mehlich 1 e Mehlich 3). As faixas alta, média e baixa originárias de outras regiões pode levar a erros de interpretação na diagnose da disponibilidade de micronutrientes nas terras pretas de índio. O Espodossolo apresentou a maior concentração de B disponível.The objective of this work was to compare extractants solutions (Mehlich 1, Mehlich 3 and DTPA-TEA) evaluating the availability of B, Cu, Fe, Mn and Zn in Amazonian Dark Earth (ADE) soils with higher fertility occurring in scattered patches throughout the Amazon, called Terra Preta do Índio (TPI). Sixteen samples of different depths were taken from ten archeology sites, and five representative soil classes of the region (Oxisol, Inceptsol, Ultisol, Entisol and Spodsol) were used. The DTPA-TEA solution extracted more Cu and Fe available, while Mehlich 1 solution extracted more Mn and Zn. At the edaphoclimatic conditions studied, the Mehlich 1 extractant showed better sensibility than Mehlich 3 and DTPA-TEA extractants. The best coefficients between extractants were observed with: Cu available (Mehlich 3 and DTPA-TEA), Fe available (Mehlich 1 and DTPA-TEA), Mn and Zn available (Mehlich 1 and Mehlich 3). The use of ranges higher, middle and lower originary in others regions can lead to incorrect interpretation of diagnoses on availability of the micronutrients in ADE soils. The Spodsol showed higher concentration of available B than others soils studieds.

Apesar da importância econômica do guaranazeiro (Paullinia cupana H.B.K. var. sorbilis (Mart.) Ducke) em algumas regiões do Brasil, existem poucas informações sobre sua caracterização fenológica. Assim, realizou-se um estudo cujo objetivo foi de quantificar a produção de fitomassa e sua distribuição, em uma população de guaranazeiros, originadas de propagação sexuada. Foram avaliadas cinco plantas adultas, que lançaram mais de 100 ramos por planta ano-1, dos quais apenas 50 % produziram frutos. As plantas lançaram entre 445 e 1294 inflorescências por ano, porém, de 67 % a 98 % produziram apenas um fruto. A produção de matéria seca total foi estimada em 15,8 kg por planta ao ano, o que corresponde 6350 kg ha ano-1. Nas plantas, o maior acúmulo de matéria seca apresentou a seguinte ordem: folhas>ramos>sementes>ráquis>casca dos frutos+arilo> pecíolos.The commerce of guarana seeds (Paullinia cupana H.B.K. var. sorbilis (Mart.) Ducke) is economically important in some regions of Brazil. However, few studies are found about its phenological characteristics. The aim of this paper was to study the production and distribution of organic matter in adult plants of guarana. Five individuals, which had more than 100 branches per plant/year, were evaluated. One found out that only 50% of the branches had fruits. The guarana plants had between 445 and 1294 inflorescences but of these, 67% to 98% had only one fruit. The total organic matter was evaluated in 15.8 kg per plant year-1 which means around 6350 kg ha year-1. The organic matter storage in guarana plant had the following sequence: leaves>branches>seeds>rachis> fruit peel+aril> petiole.

Objetivou-se utilizar técnicas de análises exploratórias em dados da produção de matéria seca (PMS) de 16 cortes de 92 cultivares de alfafa (Medicago sativa L.). A produção de matéria seca variou entre e dentro de cortes, uma vez que os coeficientes de variação oscilaram de 17,7% (corte 2) a 51,7% (corte 9). De modo geral, os dados de produção obtidos nos 16 cortes não se ajustaram à distribuição normal. Os coeficientes de simetria foram negativos nos cortes 1 a 4, 10 a 12, 14 a 16, enquanto os coeficientes de curtose foram negativos nos cortes 1, 9, 10, 12 e 16. As estimativas robustas do desvio-padrão obtidas por quatro métodos diferiram do desvio-padrão clássico (S) em todos os cortes, indicando que a estimativa S deve ser substituída por estimadores robustos.The objective was to utilize exploratory data analysis techniques for evaluating dry matter production (DMP) obtained from 16 cuts of 92 accessions of alfalfa (Medicago sativa L.). A significant effect on DMP was observed both within and among cuts; the coefficient of variation ranged from 17.7% (cut 2) to 51.7% (cut 9). The DMP data obtained from 16 cuts of 92 accessions of alfalfa did not fit to the normal distribution. The skewness coefficients were negative for dry matter production data in cuts 1 to 4, 10 to 12, and 14 to 16, while kurtosis coefficients were negative in cuts 1, 9, 10, 12, and 16. Robust estimates of standard deviation obtained from four different methods were different from the traditional standard (S) in all cuts, showing that estimate S should be replaced by these robust estimators in statistical analysis.

O feijão (Phaseolus vulgaris L.) constitui a base alimentar da população brasileira. Muitos fatores determinam a baixa produtividade do feijoeiro, desde problemas políticos até fatores técnicos, dentre eles a adubação e nutrição. O objetivo foi avaliar os atributos químicos do solo e produção do feijoeiro (cv. Pérola) de acordo com a aplicação de calagem e Mn. O experimento foi realizado em vasos com Latossolo Vermelho-Amarelo distrófico típico fase cerrado, em delineamento inteiramente casualizado com três repetições, em esquema fatorial 2 x 6, envolvendo duas doses de uma mistura de CaCO3 e MgCO3, na relação molar 3:1 (de calcário, calculadas) para elevar a saturação por base para 50 % e para 70 % e seis doses de Mn (0, 20, 40, 60, 80 e 100 mg dm-3). Na análise dos resultados, verificou-se decréscimo no teor foliar de Mn de acordo com o aumento da saturação por base, não sendo observado o mesmo efeito no solo após o cultivo. O teor de Mn no solo para produção máxima de grãos mostrou-se semelhante para saturação por base de 50 e 70 %; no entanto, a dose do micronutriente aplicada para essa produção foi de 28 mg dm-3 e 57 mg dm-3, respectivamente.Common bean is one of the most important staples in Brazil. The objective of this study was to evaluate the common bean cv. Pérola yield and changes in soil chemical attributes as influenced by liming and manganese rates. The experiment was carried out in pots containing dystrophic Red Yellow Latosol (Oxisol). Treatments consisted of a 2 x 6 factorial combination of two limestone (CO3 and MgCO3 in a 3:1 molar ratio) rates, calculated to increase base saturation to 50 and 70 %, respectively, and six Mn rates (0, 20, 40, 60, 80 and 100 mg kg-1), using MnSO4.H2O as source. There were three repetitions. Results showed that a higher base saturation reduced leaf Mn concentration, but soil Mn concentration after harvest was not altered. The soil Mn concentration sufficient to reach the maximum grain yield was similar for both 50 and 70 % base saturation, but the doses to reach such critical soil concentration were 28 and 57 mg dm-3, respectively.

Com o objetivo de avaliar a influência da relação P:Mg na fertilidade do solo, no estado nutricional e na produção de matéria seca da alfafa, foi realizado um experimento em vasos com Latossolo Vermelho Amarelo distrófico, segundo delineamento inteiramente casualizado, em esquema de parcelas subdivididas, com três repetições. Os tratamentos foram constituídos de combinações de P (doses: 0, 100, 200 e 400 mg kg-1, fonte: superfosfato triplo) e Mg (doses: 0, 100 e 200 mg kg-1, fonte: cloreto de magnésio), nas proporções de 0, 0,5, 1, 2 e 4. No período experimental, foram realizados três cortes, com intervalo de 30 dias (subparcelas). Os resultados demonstraram que o incremento da relação P:Mg e das doses de P e de Mg aumenta a produção de matéria seca. O teor de P e as combinações de P:Mg no tecido vegetal apresentaram estreita relação com a proporção desses nutrientes no solo. A relação 2:1 acarretou maior teor de clorofila e N na matéria seca, enquanto altas quantidades de P no solo diminuíram a absorção de K.A greenhouse experiment was carried out to evaluate the effect of P:Mg ratios on soil fertility and on mineral composition and yield of alfalfa cultivated in a dystrophic Red Yellow Latosol (Oxisol). It was used a split-plot in a complete randomized design, with three replicates. Treatments were combinations of P (rates: 0, 100, 200, and 400 mg kg-1, source: triple superphosphate) and Mg (rates: 0, 100, and 200 mg kg-1, source: magnesium chlorite) at the following P:Mg ratios: 0, 0.5, 1, 2, and 4. Three harvest were performed (subplots), with 30-d intervals. Results showed that dry matter yield increased with the increment of P:Mg ratios and P and Mg rates. Phosphorus concentrations and P:Mg ratios in tissue showed close relationship with the proportion of the nutrients in the soil. The 2:1 ratio caused higher chlorophyll and N concentrations in tissue, while elevating quantity of P in soil decreased K uptake.

Objetivou-se com este trabalho avaliar o efeito do ensacamento de cachos sobre a produção e qualidade dos frutos de quatro cultivares de bananeira [Thap Maeo (AAB), FHIA 18 (AAAB), Nanicão 2001 (AAA) e Prata Zulu (AAB)]. Empregou-se o delineamento experimental inteiramente casualizado em esquema fatorial 4x2, sendo os fatores: quatro cultivares e dois modos de condução (cachos ensacados e cachos não ensacados), com quatro repetições. O ensacamento foi efetuado com sacos de polietileno impregnados com inseticida organofosforado. As variáveis avaliadas foram: peso do cacho, comprimento do cacho, número de pencas, peso da segunda penca, número de frutos por penca, comprimento do fruto, espessura da casca e diâmetro da polpa. Nas condições edafoclimáticas locais, a proteção dos cachos com saco de polietileno diminuiu a produção e o diâmetro da polpa da cultivar Prata Zulu. Na cultivar Nanicão 2001, a prática do ensacamento de cachos propiciou maior comprimento dos frutos. O número de pencas, peso da segunda penca, espessura da casca, número de frutos por penca e comprimento do cacho não foram afetados pela prática do ensacamento, havendo diferenças somente entre as cultivares. O intervalo entre a inflorescência e a colheita apresentou correlação significativa somente com a produção dos cachos ensacados.The purpose of this work was to evaluate the effect of bunch protection on yield, ripening period and fruit quality of four banana cultivars [Thap Maeo (AAB), FHIA 18 (AAAB), Nanicão 2001 (AAA) and Prata Zulu (AAB)]. A randomized experimental design was employed in a 4x2 factorial comprising the four cultivars and two procedures (bagged and not bagged bunches), with four replicates. Bunches were conditioned in bags impregnated with organophosphorated insecticide. Variables analyzed were bunch weight, number of bands per bunch, bunch size, band weight, number of fruits per band, fruit length, pulp diameter, and fruit rind thickness. In local edaphoclimatic conditions, results showed that bag enclosure reduce bunch yield and pulp diameter on Prata Zulu cultivar. Protection of bunches on Nanicão 2001 increased fruit length. Number of bands per bunch, band weight, fruit thickness, number of fruits per band, and bunch size were not influenced by bag enclosure, and differences were detected only among cultivars. Time elapsed between emergence of inflorescence and fruit harvest showed significative correlation with bagged bunch yield only.

Com objetivo de induzir a brotação apical de mudas de mangostãozeiro, foi realizado um experimento que consistiu na aplicação de dois reguladores de crescimento: cinetina (0, 100 e 400 mg L-1) e giberelina (50 mg L-1), e outros dois experimentos para obtenção de estacas enraizadas: a) aplicação de ácido-indol-3-butírico nas concentrações de 0, 100, 500 e 1000 mg L-1 e b) aplicação de ácido a naftaleno acético na concentração de 6000 mg L-1. Nesses ensaios foram utilizadas estacas maduras provenientes de ramosortotrópicos. Os resultados indicaram a possibilidade do uso de reguladores para a obtenção de porta-enxertos mais uniformes e com menor tempo de formação, e apesar da baixa taxa de enraizamento, a obtenção de mudas de estacas enraizadas de mangostãozeiro obtida comfitormônios apresenta grande potencial, equivalendo em tamanho a uma muda de um ano proveniente de sementes apomíticas.With the objective to induce apical bud sprouting in youngmangosteen seedlings an experiment was carried out with the application of the plant growth regulators kinetin (0, 100 and 400 mg L-1) and gibberellin GA4+7 (50 mg L-1). To obtain rooted cuttings two other experiments were performed: a) application of indolbutyric acid at the concentrations of 0, 100, 500 and 1000 mg L-1 and b) application of a naphtaleneacetic acid, at 6000 mg L-1. In these trials cutting from orthotropic branches were utilized. The results indicated the possibility of using plant growth regulators to obtainmore uniform root stocks in a shorter nursery stage and, despite the low percentage of rooting the planting material obtained from cuttings has a great practical potential, since the size of the rooting cuttings is equivalent to that of one year old seedlings.

A utilização de sementes na propagação do guaranazeiro propicia alta variabilidade na produtividade e suscetibilidade a doenças, por isto, no Amazonas, recomenda-se a propagação do guaranazeiro por meio do enraizamento de estacas herbáceas de materiais selecionados. Objetivou-se com este trabalho, avaliar o enraizamento, em tubetes, de estacas herbáceas de doze clones de guaranazeiro submetidas a três diferentes substratos. Os clones avaliados foram o BRS 300, BRS 871, BRS 372, BRS 648, BRS 189, BRS 505, BRS 610, BRS 612, BRS 850, BRS 882, BRS 608, BRS 611. Os substratos testados foram uma mistura com base em volume de 50 % de solo + 50 % de esterco de galinha (v/v); 50 % de esterco de galinha + 50 % de carvão moído passado em peneira de 10 mm (v/v) e substrato comercial para hortaliças (Plantmax®). O substrato comercial e o esterco de galinha + carvão proporcionaram a maior porcentagem de enraizamento das estacas. O clone BRS Amazonas obteve o maior percentual de enraizamento (88,2 %), enquanto o clone BRS 372, o menor (15 %).The propagation of the guarana plants using seeds is nowadays not recommended because the high variability in the productivity and susceptibility to diseases. The cuttings propagation of a select guarana plant clones is recommended for Amazonas State. The objective of this study was to evaluate the survival rate of cuttings of twelve clones of guaraná in three substrates with three replicates. The evaluated clones were: BRS 300, BRS 871, BRS 372, BRS 648, BRS 189, BRS 505, BRS 610, BRS 612, BRS 850, BRS 882, BRS 608, BRS 611. The growing media tested were 50% of soil + 50% of chicken manure (v/v); 50% chicken manure + 50% sieved powdered charcoal (v/v) and a comercial growing media for vegetables (Plantmax®). The comercial growing media and the misture of chicken manure + sieved powdered charcoal substrate produced the higher cuttings survival rate. The clone BRS Amazonas showed the highest percentage of survival (88.2%) and clone BRS 372 the lowest (15%).