Morphogenic parameters and productivity of grass-Pioneer subjected to nitrogen

Objective of this work by evaluating the effect of nitrogen on forage yield and morphogenesis of elephant grass cv. Pioneer. The experimental design was randomized blocks with five replications, totaling 20 experimental units. Treatments consisted of four nitrogen levels (100, 200, 300 and 400 kg ha(-1) yr(-1)). The experiment was conducted under irrigated conditions. Evaluative cuts were made at 50 cm soil with values of light interception (95%) without pre-defined intervals. It was observed that N fertilization increased significantly (P<0.05) the production of dry matter per hectare, leaf appearance rate (leaves days(-1)tiller(-1)), leaf elongation rate (cm tiller(-1) day(-1)) and stem elongation rate (cm day(-1)). The process of this forage senescence is accelerated with increasing doses of nitrogen and leaf appearance rate, thereby reducing the phyllochron. It required a study on the economic viability of higher doses of nitrogen in grazed elephant grass cv. Pioneer.

Regeneração natural do componente arbóreo após a mortalidade de um maciço de taquara em um fragmento de floresta ombrófila mista em Lages - SC

The present study aimed to analyze the floristic and structural descriptors of tree species natural regeneration in a forest sector with synchronized bamboo (Merostachys multiramea Hackel) die-off (CT) and an adjacent area with continuous canopy cover (ST) in an araucaria forest fragment in the municipality of Lages, Santa Catarina state. A total of 14, 5x5m, plots (six plots in CT sector and eight in ST sector) were allocated, where all tree species regenerative individual with circumference at breast height smaller than 15cm and height higher than 25cm was measured (diameter at soil level) and identified. The richest families were: Myrtaceae (nine), Solanaceae (six) and Aquifoliaceae (four). The Shannon Diversity Index in ST and CT sectors were respectively 2.73 and 2.31. The species with the highest importance values in CT sector were Solanum variabile, Piptocarpha angustifolia, Mimosa scabrella, Jacaranda puberula and Solanum pseudoquina. In ST sector, the species with highest importance values were Myrsine lorentziana, Casearia decandra, Cinnamodendron dinisii, Drimys brasiliensis and Ilex paraguariensis. The results showed that the synchronized bamboo die-off influenced the spatial variation in the floristic and structural descriptors of the tree species natural regeneration.

Caracterização física e química dos frutos nos diferentes quadrantes da planta e germinação de sementes do portaenxerto cítrico tangerineira ‘sunki’

The tangerine 'Sunki' are highly relevant for the Brazilian citrus industry by presenting important traits for genetic improvement and to be considered a great portaenxento. In this context, the objective of the present work to study the characterization of the fruits of citrus rootstock 'Sunki', depending on the position on the plan and also the germination of their seeds. The physical characteristics evaluated were fruit weight, longitudinal and equatorial diameters of the fruit longitudinal diameter / equatorial diameter, number of buds per fruit, weight of buds and bark and number of viable seeds per fruit. As for the chemical characterization was evaluated titratable, acidity, soluble solid, "Ratio", pH and vitamin C. For the evaluation of these variables, the fruits were obtained from the northeast, southwest, northwest and southeast quadrants. Regarding the evaluation of seed germination, different doses of gibberellic acid and Stimulate were used. The seeds extracted from ripe fruit, washed, dried in the shade and stored in BOD. Immediately after, they were treated for 24 hours with plant growth regulators. After soaking, the seeds were placed in a germinator in germitest paper. After initiation of the germination process, the evaluations were performed daily until the thirty- fourth day. Fruits of 'Sunki'mandarin with uneven as the fruit position within the canopy, the use of gibberellic acid and growth promoter is promising for commercial use on seed germination of this rootstock.

Maize leaf phytotoxicity and grain yield are affected by nitrogen source and application method

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Desenvolvimento inicial de maracujazeiros (Passiflora edulis f. flavicarpa, P. edulis f. edulis e P. alata) enxertados sobre Passiflora cincinnata

The present work aimed to evaluate the initial growth and leaf mineral levels in passion fruit trees (Passiflora edulis f. flavicarpa Deg., P. edulis f. edulis Sims. and P. alata Dryander) grafted onto Passiflora cincinnata. To obtain seedlings, seeds were sown in plastic bags (500 mL) and hypocotyl grafting was performed when seedlings reached the stage of two fully expanded leaves. Fifteen days after grafting, plants were transplanted to 10L pots filled with previously limed and fertilized soil. Each pot contained two plants and corresponded to one plot. For each commercial species studied as rootstock, experimental design was completely randomized, in 3x5 (plant type x time of harvest) factorial arrangement, with four replicates of two plants per plot and five destructive harvests. Plant types were ungrafted P. cincinnata, ungrafted commercial passion fruit tree and commercial passion fruit tree grafted onto P. cincinnata. The first harvest was performed at 15 days after transplanting and the remaining ones at 14-day intervals (60, 74, 88, 102 and 116 DAS). At each harvest, the number of leaves per plant was counted, and leaf area, stem length, and stem, root, leaf and total dry matter were estimated. At the last harvest, the mineral composition (macro and micronutrients) of plants was analyzed. In general, it was observed that grafting onto P. cincinnata did not interfere negatively with the initial development and mineral levels of commercial passion fruit trees, and this interference varied according to the used canopy.

Complete genome sequence and structural characterization of a novel iflavirus isolated from Opsiphanes invirae (Lepidoptera: Nymphalidae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Dinâmica espaço-temporal da ocorrência de nematoides em seringueira

Pós-graduação em Ciência Florestal - FCA

O campo térmico e a qualidade ambiental urbana em Chapecó/SC

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Utilização da modelagem sistêmica para analisar o efeito da variação climática no parâmetro produtividade da água na laranja Natal (Citrus sinensis L. Osbeck) no Estado de São Paulo

Pós-graduação em Agronomia (Irrigação e Drenagem) - FCA

Estruturação de metacomunidades de girinos em diferentes fitofisionomias da Mata Atlântica: uma análise em diferentes escalas espaciais

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Fluxo de gases de efeito estufa na implantação de sistema silvipastoril em pastejo com ovinos

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Plantas e formigas em diferentes usos da terra e técnicas de restauração no Cerrado

Pós-graduação em Ciência Florestal - FCA

Caracterização espectral de espécies de Mata Atlântica de Interior em nível foliar e de copa

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Eficácia do flutriafol e do flutriafol + tiofanato metílico aplicados com gotas finas ou médias no controle da ferrugem asiática da soja

The aim of this study was to evaluate the influence of fine and medium droplets in the performance of flutriafol and thiophanate methyl + flutriafol for the control of Asian Soybean Rust (Phakopsora pachyrhizi Sydow & Sydow). The experiment was a 2 x 2 factorial design (2 droplet sizes x 2 fungicides) resulting in four treatments with six replications. The experimental area was set up with 24 plots (50 x 21 m). In each plot there was a central assessment area with 10 x 20 m. To the each plot there was a non-treated area placed in opposed direction to the wind. The evaluations of rust control were made by of the calculation of incidence (percentage of plants with rust), severity (level of infection), defoliations and soybean yield. The results were analyzed by the calculation of the confidence interval at 90%. The study was set up in curative control conditions with average infestation of 68.6%, average severity in the lower part of the canopy was of 35.9% and on the upper parte it was 4.57%. The results of severity, defoliation and productivity did not show statistical difference among the treatments. However, it was observed that in general there was tendency of better results with the application of flutriafol alone comparing with thiophanate methyl + flutriafol, since there was a small difference between two commercial products in the flutriafol active ingredient content (62.5 g ha-1 to the flutriafol alone and 60 g ha-1 to the thiophanate methyl + flutriafol). There was no statistical difference between fine and medium droplets. This fact can be explained by the characteristics of systemic action of the flutriafol and by the type of control made (curative). The flutriafol, being a systemic fungicide is less sensitive to the better coverage provided by the smaller droplets and, on the curative control, the amount of product deposited can became more import than coverage, mainly on the superior part of the leaves. These leaves are healthier than the inferior leaves that in general are the first to become completely compromised by the rust, losing importance to the plant. By this reason, medium droplets appear to have offered similar performance even not offering advantages in the leaf coverage. This fact may become important because in the practical side of the use of medium droplets, since this may increase the amount of time to spray, mainly because the fine and very fine droplets have more limitations related to drift and evaporation.

Uso do fluxofenim em trigo como protetor ao herbicida S-metolachlor

This work aimed to evaluate the effectiveness of fluxofenim used for seed treatment as safener in wheat, Ônix cultivar, treated with the herbicide S-metolachlor applied in pre-emergence. The study was divided in two steps. The first step consisted of an evaluation of fluxofenim’s safener potential for the reduction of visual symptoms of S-metolachlor injury in the field, and the treatments were S-metolachlor at 1,440 and 2,880 mL i.a. ha-1 and fluxofenim at 0, and 40 mL per 100 kg of seeds, and a control without herbicide. The second step was to evaluate glutathione S-transferase activity (GST). Herbicide phytotoxity was measured by way of visual symptoms at 3, 7, 15, and 30 days after emergence (DAE), dry matter from roots and leaves at 10 DAE. For the determination of GST activity, the canopy of plants was collected at 10 DAE and 15 days after treatment application. The wheat presented low tolerance to S-metolachlor at both rates, and fluxofenim increased S-metolachlor selectivity to wheat but not sufficiently, reducing plant population to a nonacceptable level. Gluthationa S-transferase activity for wheat increased when seeds treated with fluxofenim were submitted to S-metolachlor at 1,440 mL a.i. ha-1.