Regynaldo Arruda Sampaio

Fibra de coco e resíduo de algodão para substrato de mudas de tomateiro

A greenhouse experiment was carried out to evaluate fiber mixture of coconut and cotton waste, to produce substrate for tomato seedling production (cultivar Kada Gigante). The experimental design was randomized blocks, four replications, with seven treatments: T1) Commercial Substrate Hortimix®; T2) 0% coconut dry fiber mass (FC)+100% dry mass of cotton waste (RA); T3) 20% (FC)+80% (RA); T4) 40% (FC)+60% (RA); T5) 60% (FC)+40% (RA); T6) 80% (FC)+20% (RA); T7) 100% (FC)+0% (RA). The vigor was evaluated in terms of percentage and index of emergence, stem diameter, seedling height. Increasing the proportion of coconut fiber to cotton waste ratio resulted in an increase of percentage and index of emergence; however, the stem diameter, seedling height, shoot and root fresh and dry mass decreased. The residue of cotton proceeding from the compostage of residues of the textil factory, constitutes in a useful material in the commercial substrate production.

Produção de mudas de tomateiro em substratos contendo fibra de coco e pó de rocha

ABSTRACT Tomato seedlings production using substrates with coconutfiber and rock waste A greenhouse experiment was carried out to evaluate the ratioof coconut fiber and rock waste, in the tomato seedling production(cultivar Kada Gigante), in Montes Claros, Brazil. The experimentaldesign was of randomized complete blocks with four replicates. Thetreatments were composed of a control and six ratios of coconutfiber (FC) and rock waste (RG): T 1 - Commercial SubstrateHortimix ® ; T 2 - 0% FC + 100% RG; T 3 - 20% FC + 80% RG; T 4 -40% FC + 60% RG; T 5 - 60% FC + 40% RG; T 6 - 80% FC + 20%RG; T 7 - 100% FC + 0% RG. The cultivation was done in polystyrenetrays with cells of 3.5 x 3.5 x 5,0 cm. Stem diameter, seedling height,emergency speed index, emergency percentage, root and aerial partof fresh and dry matter were evaluated. In almost all the evaluatedcharacteristics the commercial substrate was better than the substratescontaining coconut fiber and rock waste. Among the substratescontaining coconut fiber and rock waste, the seedlings with bettercharacteristics were obtained with a mixture of approximately 70%of the volume of coconut fiber.

Crescimento de mudas de pinhão-manso em resposta a adubação com superfosfato simples e pó-de-rocha

Research into rock-flour have shown the potential of some of these residues in promoting the mineral enrichment of soils; a practice defined as stonemeal soil. Such practice aims to increase soil fertility and provide good productivity and greater agricultural sustainability. The present study had as objective to evaluate the growth of jatropha seedlings (Jatropha curcas L.) in response to fertilization of the substrate with single superphosphate and rock-flour. The experiment was setup and conducted from September to November, 2007, in a greenhouse at the Institute of Agricultural Sciences/UFMG. The treatments, in a 2 x 5 factorial design of randomized blocks, with three replications, corresponded to two doses of rock-flour (0 and 20 kg m-3 of substrate) and 5 doses of single superphosphate (1.25, 2.5, 5.0, 7.5 and 10.0 kg m-3 of substrate). Plant height, stem diameter, plant height/stem diameter ratio, number of leaves per plant, leaf area, fresh and dry matter of root and shoot, total fresh and dry matter, shoot/root dry-matter ratio, dry matter content and the Dickson quality index- IQD, were all evaluated. The results show no significant interaction between the levels of phosphorus and rock-flour applied and the variables studied. The application of single superphosphate was significant for plant height, stem diameter, leaf area, root, shoot and total fresh matter, with a positive response up to the maximum applied phosphorus dosage.

Zoological diversity associated to a silvopastural system leucaena-guinea grass with different establishment times

The aim of this work was to evaluate the associated zoological diversity of a silvopastural system leucaena-guinea grass, by characterizing the composition and structures of the birds, insects and the macrofauna of the soil, in four establishment times of the silvopastural systems (3, 4, 5 and 6 years of exploitation). For the species recorded in each zoological group, the following ecological indices were determined: number of individuals, richness, diversity and abundance of species, in each establishment times of the system. A significant increase, in all the zoological groups, was observed for the richness of species and for the index of biological diversity of Shannon, as the system developed. An increase in the abundance of bioregulator insects was observed, and for the birds, the sampling time showed no interaction with the different sowing years. The macrofauna of the soil increased during the management of the system, and a dominance of annelids (Polyferetrina elongata and Oligochaeta elegans) was noted during the 6th and 7th year of exploitation. The silvopastural system leucaena-guinea grass increases the biomass production and other biological components, and contributes to create a sustainable system which is compatible with the environment.

Irrigação e adubação nitrogenada em milho

The aim of this work was to study the effects of water and nitrogen application on corn crop components (BR 201) and productivity in the cerrado area of Roraima, Brazil. The statistical analysis consisted of a 4 X 4 randomized block design, using split plots with 16 treatments and 4 replications. The four water depths used were 392.6; 337.6; 282.6 and 227.6mm and the four nitrogen rates were 0; 50; 100 and 150 kg ha-1. The water depth used influenced the height of the corn plant. Irrigation and nitrogen levels influenced the mass of 100 seeds, the number of ears per hectare and the grain productivity. The seed N levels were linearly influenced by the nitrogen fertilization.

Metais pesados e patógenos em milho e feijão caupi consorciados, adubados com lodo de esgoto

The objective of this work was to evaluate the effect of fertilization with sewage sludge submitted to different treatments of sanitization on contamination with heavy metals and pathogens in soil and grains of maize - cowpea intercropping system. The experimental design was completely randomized blocks with three replicates, corresponding to: soil without fertilization; liming and chemical fertilization; sewage sludge; sewage sludge sanitized with nim; sewage sludge sanitized with lime; composted sewage sludge and ipomoea; sewage sludge and ipomoea composted with rock phosphate; sewage sludge with rock phosphate incorporated in the soil; sewage sludge sanitized with nim and rock phosphate incorporated in the soil; sewage sludge sanitized with lime and rock phosphate incorporated in the soil; sewage sludge and ipomoea composted with rock phosphate incorporated in the soil. The pathogen density in the soil was extremely low and there were no differences between treatments. The heavy metal concentrations in the soil, including sewage sludge, did not surpass the maximum limits of annual addition and the permissible maximum limits for soils. In spite of this, the concentrations of Pb in maize grains, and Pb and Cr in cowpea grains, reached values above the limits permitted for agricultural products, independent of the addition of sewage sludge in the soil. In general, no influence of type of sewage sludge in relation to content of heavy metals in grains of corn and cowpea was observed.

Metais pesados em milho fertilizado com fosfato natural e composto de lodo de esgoto

Em virtude do elevado teor de nutrientes e materia orgânica o lodo de esgoto tem sido reportado em diversos trabalhos, como excelente adubo orgânico. Entretanto, a presenca de metais pesados pode inviabilizar sua utilizacao agricola. Objetivou-se, com este trabalho, avaliar os teores de metais pesados no solo e em folhas de milho fertilizado com fosfato natural e composto de lodo de esgoto. O trabalho foi realizado em area experimental do ICA/UFMG, em CAMBISSOLO HAPLICO, em Montes Claros, MG. Os tratamentos, em esquema fatorial 2 x 4, foram constituidos de 2 doses de fosfato natural reativo (0 e 90 kg ha-1 de P2O5) e 4 doses de composto de lodo de esgoto (0; 25; 50 e 75 Mg ha-1). O delineamento experimental utilizado foi em blocos casualizados, com 3 repeticoes dos tratamentos e 180 plantas por parcela. De modo geral, o fosfato natural nao influenciou os teores de metais pesados no solo; entretanto, os teores de Cu, Zn e Pb no solo aumentaram com a aplicacao de doses de composto de lodo de esgoto. Aplicacoes de doses de composto de lodo de esgoto de ate 75 Mg ha-1 nao aumentaram os teores de Cu, Zn, Pb, Cd, Ni e Cr acima dos limites criticos estabelecidos pela legislacao. Na planta, os teores de Cu, Zn, Pb, Cd e Cr nao foram influenciados pela aplicacao de fosfato natural porem o teor de Zn aumentou e o de Pb reduziu com a aplicacao de doses de composto de lodo de esgoto.

Características químicas de solos salino-sódicos submetidos a parcelamento da lâmina de lixiviação

In saline-sodic soils, even with gypsum appliance, immediate leaching of salts can promote the dispersion of clay and the impermeability of the soil, hindering soil recovery. The objective of this work was to evaluate the influence of the parceled leaching on diverse chemical characteristics of a saturated soil paste extract, in saline-sodic soil samples. Columns of PVC were filled with samples of soils Fluvent of Ipanguacu, RN, Fluvent of Caico, RN and Vertisol (V) of Mossoro, RN, Brazil. The management consisted in applying leaching solution, with CaCl2 and MgCl2, with the total volume and parceled in two, four and six times, with intervals of 22 days among appliances. In the saturated soil paste extract, the electrical conductivity, pH and concentration of sodium, calcium, magnesium and sulfates were determined. The pH and cations exchangeable were determined in the soil. The application of gypsum and water depth reduce the exchangeable sodium percentage and the electrical conductivity of saturated soil paste extract to values lower that 15% and 4 dS m-1, respectively, mainly when the water depth is applied in parcel.

Nutrição mineral do mangarito num Latossolo Vermelho Amarelo

The aim of this work was to characterize the nutritional limitations for dry matter production of Xanthosoma mafaffa (L.) Schott. The experiment was carried out in a greenhouse with 0-20 cm samples of a Oxisol under cerrado vegetation, collected at Montes Claros, Minas Gerais State, Brazil. The cultivation was conducted in 3 L pots. The experimental design was totally randomized with 13 treatments and three replications. Treatments were based on the missing element technique (with omission of liming and each one of the macro and micronutrients). The decreasing order of treatments that more influenced the aerial dry matter production was: -liming> -P > -S > test > -B > -liming+Ca+Mg > -N > -K. The omission of Ca, Mg, Zn and Cu did not influence the aerial dry matter production. The decreasing order of treatments that influenced the root dry matter production was: -B > - Mg > -liming+Ca+Mg > -K > -N > -Zn > -liming > -S > -Cu > -Ca > -Cu > -Ca > test > -P.

CRESCIMENTO INICIAL DE EUCALIPTO E ACÁCIA, EM DIFERENTES ARRANJOS DE INTEGRAÇÃO LAVOURA-PECUÁRIA-FLORESTA

The objective was to evaluate initial growth of clonal Eucalyptus, hybrid Eucalyptus grandis x E. urophylla and Acacia (Acacia mangium) trees in alternate and not alternate rows of trees, intercropped with forage (crop-livestock-forest integration - CLFI) and monoculture. The design was a randomized complete block design with four replications, three arboreal arrangements consisting of eucalyptus, acacia + eucalyptus, acacia, all planted in crop-livestock-forest integration and two monoculture controls (Eucalyptus and Acacia). The height of eucalyptus trees is influenced by the consortium with Acacia in the studied CLFI designs, which does not happen with the diameter at breast height. The arrangement of species of eucalyptus and acacia intercropping in the same row planting has productivity equal to the array using only the lines of eucalyptus planting systems . Timber productivity of acacia and eucalyptus in the same row is less than the same species line, however, the sum of the timber produced from the two species is greater than the arrangement of eucalyptus only row in CLFI.