ESTUDOS DA MARCHA DE ABSORÇÃO DE NUTRIENTES PARA RECOMENDAÇÃO DE ADUBAÇÃO NO CULTIVO DA CEBOLA

O objetivo deste trabalho foi estabelecer uma recomendação mais precisa de adubação, considerando a fenologia e a exigência nutricional das plantas. A recomendação foi elaborada com base em pesquisas científicas recentes, que abordam a curva ou marcha de absorção de nutrientes, realizados em campo aberto nas condições edafoclimáticas do estado de São Paulo. Os critérios de recomendação foram: valores atuais de produtividade da cultura da cebola, população de plantas por hectare e métodos utilizados para extração dos nutrientes analisados. As quantidades dos adubos foram calculadas a partir da recomendação de cada nutriente, determinada em função da curva de acúmulo de nutrientes da cultura. Além disso, foi considerada a eficiência de aproveitamento dos nutrientes pelas plantas de acordo com o tipo de solo e o sistema de cultivo. Verificou-se que a maior exigência nutricional da cultura da cebola ocorre durante a bulbificação. É importante destacar que a quantidade de cada nutriente a ser aplicada depende das condições climáticas, do tipo de solo, do sistema de irrigação e do manejo cultural

CARACTERÍSTICAS FÍSICO-QUÍMICAS DE FRUTOS DE TOMATEIRO EM FUNÇÃO DE DOSES DE FÓSFORO NA FASE DE MUDAS

Objetivou-se avaliar as características físico-químicas de frutos de tomateiroem função de doses de fósforo na fase de produção de mudas. Utilizou-se o delineamento experimental em blocos casualizados, em esquema de parcelas subdivididas, sendo as parcelas as doses de fósforo e as datas de colheita dos frutos as subparcelas. Foram aplicados avaliados seis tratamentos (doses de P): 0, 15, 30, 45, 60 e 75 mg de P L-1 , utilizando-se fosfato monoamônio. Avaliaram-se características físico-químicas dos frutos em quatro colheitas: pH, acidez titulável, sólidos solúveis, açúcares redutores, ácido ascórbico, índice de maturação, clorofila a e b, licopeno e β-caroteno. Os resultados encontrados permitem concluir que doses de fósforo aplicado durante a fase de mudas não afetam as características físico-químicas dos frutos de tomateiro. Observa-se redução no pH e acidez titulável, e aumento no teor de sólidos solúveis, índice de maturação, ácido ascórbico e licopeno com o avanço das colheitas

Nitrogen doses and splitting in top dressing in the production and macronutrient content in fruits of zucchini

Nitrogen fertilization in cucurbits must be splitted, one part being supplied before planting and the rest applied in top dressing. However, there is a lack of research about this splitting throughout the cycle. The objective of this study was to evaluate the effect of nitrogen doses and splitting of this fertilization in top dressing on production and macronutrient content in fruits of zucchini. Two experiments were carried out, with thirteen treatments, in the factorial scheme 4x3+1, with four nitrogen doses in top dressing (62.5, 125.0, 187.5, 250.0 kg ha-1 of N), three splitting forms (1/6+1/3+1/2; 1/4+1/2+1/4; 1/3+1/3+1/3 of total dose in each application) and one treatment without fertilization in top dressing (control = dose zero), with four replicates. Experiment 1 and 2 were conducted in 2014 and 2015, respectively. Total and commercial fruit production (g), total and commercial fruit number per plant, length, diameter and average commercial fruit weight were evaluated. Only in experiment 2 the macronutrient content in the fruits were evaluated. In experiment 1, the 1/4+1/2+1/4 splitting provided greater number of total and commercial fruits per plant. In experiment 2, the increasing of the doses in the 1/6+1/3+1/2 and 1/3+1/3+1/3 splitting resulted in a linear increase in total and commercial fruit production. The decreasing order of macronutrient content in fruits was K>N>P>Ca>Mg>S

Desempeño productivo y cualitativo de plantas de tomate en relación con la aplicación de reguladores de crecimiento y nutrientes minerales

1 recurso en línea (páginas 416-424).The tomato fruit is rich in antioxidant compounds and has great nutritional and economic importance, annually promoting research on the nutritional and productive characteristics. The present study aimed to evaluate whether foliar application of commercial products based on growth regulators [auxin, cytokinin and gibberellin (Ax+CK+GA)], micronutrients [cobalt and molybdenum (Mi)] and mixtures of macro and micronutrients [nitrogen, boron, copper, molybdenum and zinc (Ma+Mi)], isolated and in combination, increase productivity and improve the post-harvest quality of tomato fruits (Predador F1). The experiment design used randomized blocks, with seven treatments and four repetitions, which were (T1) control; (T2) Ax+CK+GA; (T3) Ma+Mi; (T4) Mi; (T5) Ax+CK+GA + (Ma+Mi); (T6) Ax+CK+GA + Mi; and (T7) Ax+CK+GA + Mi + (Ma+Mi). The variables production, precocity, soluble solids content (SS), titratable acidity (TA), ratio (SS/TA), pH, total soluble sugars, ascorbic acid and weight loss were evaluated. The Ax+CK+GA application, isolated or in combination with Ma+Mi, promoted the precocity, and the use of isolated Ax+CK+GA and Mi improved the tomato plant productivity. The growth regulators, macro and micronutrients, isolated or in combination, increased the ascorbic acid content in the fruits.El tomate es un fruto rico en compuestos antioxidantes y tiene gran importancia nutricional y económica; anualmente se promueve investigaciones relacionadas con las características nutricionales y productivas. El objetivo de este estudio fue evaluar si la aplicación foliar de productos comerciales a base de reguladores vegetales [auxina, citocinina y giberelina (Ax+CK+GA)], micronutrientes [cobalto y molibdeno (Mi)] y mezcla de macro y micronutrientes [nitrógeno, boro, cobre, molibdeno y zinc (Ma+Mi)], de forma individual y combinada, sobre el aumento de la productividad y mejora de la calidad poscosecha de los frutos de tomate (Predador F1). El diseño experimental consistió en bloques al azar, con siete tratamientos y cuatro repeticiones, siendo (T1) control; (T2) Ax+CK+GA; (T3) Ma+Mi; (T4) Mi; (T5) Ax+CK+GA + (Ma+Mi); (T6) Ax+CK+GA + Mi; (T7) Ax+CK+GA + Mi + (Ma+Mi). Se evaluaron las variables producción, precocidad, contenido de sólidos solubles (SS), acidez titulable (AT), relación SS/AT, pH, azúcares solubles totales, ácido ascórbico y pérdida de peso. La aplicación de Ax+CK+GA de forma individual o combinada con Ma+Mi promovió la precocidad, mientras el uso de Ax+CK+GA y Mi, de forma separada, mejoró la productividad del tomate. Los reguladores de crecimiento y los macro y micronutrientes, separados o combinados, proporcionaron un aumento en el contenido de ácido ascórbico en los frutos.Bibliografía y webgrafía: páginas 422-42

Observation of the Rare Decay of the η Meson to Four Muons

A search for the rare η→μ+μ−μ+μ− double-Dalitz decay is performed using a sample of proton-proton collisions, collected by the CMS experiment at the CERN LHC with high-rate muon triggers during 2017 and 2018 and corresponding to an integrated luminosity of 101  fb−1. A signal having a statistical significance well in excess of 5 standard deviations is observed. Using the η→μ+μ− decay as normalization, the branching fraction B(η→μ+μ−μ+μ−)=[5.0±0.8(stat)±0.7(syst)±0.7(B2μ)]×10−9 is measured, where the last term is the uncertainty in the normalization channel branching fraction. This work achieves an improved precision of over 5 orders of magnitude compared to previous results, leading to the first measurement of this branching fraction, which is found to agree with theoretical predictions

Search for new physics in multijet events with at least one photon and large missing transverse momentum in proton-proton collisions at 13 TeV

A search for new physics in final states consisting of at least one photon, multiple jets, and large missing transverse momentum is presented, using proton-proton collision events at a center-of-mass energy of 13 TeV. The data correspond to an integrated luminosity of 137 fb−1, recorded by the CMS experiment at the CERN LHC from 2016 to 2018. The events are divided into mutually exclusive bins characterized by the missing transverse momentum, the number of jets, the number of b-tagged jets, and jets consistent with the presence of hadronically decaying W, Z, or Higgs bosons. The observed data are found to be consistent with the prediction from standard model processes. The results are interpreted in the context of simplified models of pair production of supersymmetric particles via strong and electroweak interactions. Depending on the details of the signal models, gluinos and squarks of masses up to 2.35 and 1.43 TeV, respectively, and electroweakinos of masses up to 1.23 TeV are excluded at 95% confidence level

Search for Scalar Leptoquarks Produced via τ-Lepton-Quark Scattering in pppp Collisions at s=13TeV\sqrt{s}=13 TeV

The first search for scalar leptoquarks produced in τ-lepton–quark collisions is presented. It is based on a set of proton-proton collision data recorded with the CMS detector at the LHC at a center-of-mass energy of 13 TeV corresponding to an integrated luminosity of 138  fb$^{−1}$. The reconstructed final state consists of a jet, significant missing transverse momentum, and a τ lepton reconstructed through its hadronic or leptonic decays. Limits are set on the product of the leptoquark production cross section and branching fraction and interpreted as exclusions in the plane of the leptoquark mass and the leptoquark-τ-quark coupling strength

Search for new physics in high-mass diphoton events from proton-proton collisions at √s = 13 TeV

Results are presented from a search for new physics in high-mass diphoton events from proton-proton collisions at sqrt(s) = 13 TeV. The data set was collected in 2016–2018 with the CMS detector at the LHC and corresponds to an integrated luminosity of 138 fb−1 . Events with a diphoton invariant mass greater than 500 GeV are considered. Two diferent techniques are used to predict the standard model backgrounds: parametric fts to the smoothly-falling background and a frst-principles calculation of the standard model diphoton spectrum at next-to-next-to-leading order in perturbative quantum chromodynamics calculations. The frst technique is sensitive to resonant excesses while the second technique can identify broad diferences in the invariant mass shape. The data are used to constrain the production of heavy Higgs bosons, Randall-Sundrum gravitons, the large extra dimensions model of Arkani-Hamed, Dimopoulos, and Dvali (ADD), and the continuum clockwork mechanism. No statistically signifcant excess is observed. The present results are the strongest limits to date on ADD extra dimensions and RS gravitons with a coupling parameter greater than 0.1