Adriana G. Magalhães

Desenvolvimento e acúmulo de macronutrientes em plantas de milho biofertilizadas com manipueira

Objetivou-se, neste estudo, avaliar o desenvolvimento vegetativo e o acumulo de macronutrientes em plantas de milho submetidas as doses de manipueira. O experimento foi conduzido em ambiente protegido no periodo de marco a maio de 2011. O delineamento experimental foi inteiramente casualizado em esquema fatorial 2 (tipos de solo: franco-arenoso e franco-argiloso) × 4 (doses de manipueira: 0; 11,2; 22,4 e 44,8 m3 ha-1), com oito repeticoes. As variaveis analisadas foram: altura das plantas, diâmetro de colmos, numero de folhas, materia fresca e materia seca da parte aerea das plantas e teores de N, P, K, Ca e Mg no tecido foliar. O aumento das doses de manipueira elevou o conteudo de massa fresca, o teor de nitrogenio e potassio da parte aerea das plantas, mas diminuiu a altura das plantas e o teor de magnesio na parte aerea das plantas. Os acrescimos de materia seca e de calcio na parte aerea das plantas foram maiores no solo franco-arenoso.

Alterações dos atributos físicos e químicos de um Neossolo após aplicação de doses de manipueira

The effluent from cassava industrial processing presents high ionic organic charge and high nutrient concentration. If discarded indiscriminately in soil, this effluent may cause serious environmental hazard. The objective of this paper is to evaluate changes in physical and chemical attributes of a soil cultivated with lettuce and submitted to increasing doses of cassava wastewater. The experiment was carried out under greenhouse in a completely randomized design with six treatments consisting of application of 0, 5, 15, 25, 45 and 65 m3 ha-1 and five replications. Soil physical (degree of flocculation, dispersed clay in water) and chemical (electrical conductivity of saturation extract of soil, pH, content of P and exchangeable cations K+, Ca2+, Mg2+ and Na+) properties were evaluated for soil characterization. Besides decreasing clay dispersed in water, use of cassava wastewater in the soil increased flocculation degree, pH, electrical conductivity of saturation extract, exchangeable cations and P content. Tendency of soil salinization was observed after cassava wastewater application.

Variabilidade espacial de atributos físicos e mecânicos de um Argissolo sob cultivo de cana-de-açúcar

The purpose of this study was to evaluate the spatial relation of physical and mechanical attributes of a cohesive Ultisol cultivated with sugarcane. Forty nine georeferenced points were established for the collection of samples, with 7 x 7 grid, forming a mesh of 120 x 120 m. The trenches were opened at two layers (0-20 and 20-40 cm) for the collection of disturbed and undisturbed samples. The normal distribution was observed in all variables. Strong degree of spatial dependence was also observed for most variables. The plastic limit showed nugget effect. The highest range was found for the liquid limit (0-20 cm) compaction degree (0-20 cm) and lowest for soil moisture (0-20 cm), IP and organic carbon (20-40 cm). Kriging maps showed an inverse correlation between density and porosity and strong correlation between clay and organic carbon as well as between the clay and the limits of consistence. For most variables, there was spatial dependence up to 20 m, indicating that for parametric analysis, samples should be collected at distances over 20 m.

Variabilidade genética em progênies de meios-irmãos de coentro

A large number of producers are involved in the cultivation of coriander throughout the year in Brazil, making it a crop of social and economic importance. Throughout nearly the entire Northeast Region, cultivar Verdao is used. Genetic variability studies on coriander are important for the proper planning of genetic improvement programs. The aim of the present study was to quantify the genetic variability for agronomic characteristics in cv. Verdao to contribute information toward genetic improvement. The study was developed at Universidade Federal Rural de Pernambuco, Pernambuco State, Brazil, in a greenhouse, using randomized blocks of 28 plants in two pots and five replications. The treatments were composed of 55 half-sib progenies from cultivar Verdao. The t test detected significance at 1 and 5% likelihood between the genotypic, phenotypic and environmental correlations. Broad sense heritability ranged from 7.19 for average plant weight to 81.09 for number of bolted plants. The ratio between genetic and environmental coefficients of variation (CVg/CVe) ranged from 0.27 (average weight) to 2.07 (number of bolted plants), indicating that selection against bolting presents more favorable conditions in terms of immediate genetic gains. The genotype correlation between height of non-bolted plants and the number of bolted plants was considered strong (0.86) and highly significant (t test), enabling simultaneous gains from selection.

Desenvolvimento inicial do milho submetido à adubação com manipueira

This research aimed to evaluate the effect of cassava wastewater fertilization on maize growth. The experiment was carried out under greenhouse conditions at the Federal Rural University of Pernambuco (Brazil). Treatments were assigned in a factorial arrangement 5 x 3, being 5 cassava wastewater doses: 0, 12.6, 25.2, 50.4 and 75.6 m3 ha-1 and 3 harvest ages: 20, 40, and 52 days after germination (DAG), in a completely randomized design, with four replications. A hybrid of forage maize (AG 1051) was used, keeping one plant in a 20 L pot. The variables evaluated were: plant height, stalk diameter, number of leaves, dry and fresh matter of leaves and stalks. The dose equivalent to 63 m3 ha-1 provided the highest gain in stalk diameter, number of leaves, dry and fresh matter of leaves; while the dose equivalent to 75.63 m3 ha-1 provided significant increase in the other evaluated phenological parameters. Cassava wastewater presented as a useful fertilization source for maize crop, however responses depended on utilization of appropriated cassava wastewater doses.

Desempenho de cultivares de alface em cultivo hidropônico sob dois níveis de condutividade elétrica

. Os tratamentos foram as cultivares de alface Baba de Verao, Floresta, Luisa, Manoa, Regina 579, Saia Veia e Vitoria Verdinha. O delineamento experimental foi blocos casualizados, com tres repeticoes. A colheita foi feita aos 45 dias apos a semeadura. Nenhuma cultivar se destacou no conjunto das caracteristicas avaliadas, embora a Manoa tenha apresentado o maior indice de queima de bordas das folhas, sem diferir estatisticamente da Saia Veia e Baba de Verao. As cultivares Regina 579 e Vitoria Verdinha sao as preferidas dos produtores hidroponico de Pernambuco, devido a falta de genotipos mais adaptados a essa modalidade de cultivo, e por apresentarem folhas lisas, levemente enrugadas e de textura macia.

Spatial Dependence of Physical Attributes and Mechanical Properties of Ultisol in a Sugarcane Field

This study investigates the effect of conventional tillage and application of the monoculture of sugar cane on soil health. Variables like density, moisture, texture, consistency limits, and preconsolidation stress were taken as indicators of soil quality. The measurements were made at a 120 × 120 m field cropped with sugar cane under conventional tillage. The objective of this work was to characterize the soil and to study the spatial dependence of the physical and mechanical attributes. Then, undisturbed soil samples were collected to measure bulk density, moisture content and preconsolidation stress and disturbed soil samples for classification of soil texture, and consistency limits. The soil texture indicated that soil can be characterized as sandy clay soil and a sandy clay loam soil, and the consistency limits indicated that the soil presents an inorganic low plasticity clay. The preconsolidation tests tillage in soil moisture content around 19% should be avoided or should be chosen a management of soil with lighter vehicles in this moisture content, to avoid risk of compaction. Using geostatistical techniques mapping was possible to identify areas of greatest conservation soil and greater disturbance of the ground.