Produção de cebola em solo salinizado

The use of water or soil with a high salt concentration has been the main cause of failure in the yield of many crops. Consequently, this work aimed at evaluating the effects of different salinity levels and soil moisture on onion yield (cultivar Baia periforme). An experiment was conducted in a greenhouse of the Soil Science Department - FCA - UNESP, Botucatu, SP, in pots of 10 L. The soil was salinized with NaCl in order to increase the electrical condutivity of saturation extract of soil from 0.13 to 2; 4; 6 and 8 dS m-1. In each experimental unit 15.2 g of thermophosphate enriched by micronutrients and 1.5 L of organic matter were incorporated. The moisture treatments kept the soil within the limits of 25-50, 50-75 and 75-100 % of field capacity. The plant height the pseudostem diameter and yield of bulbs were evaluated. The results lead to the conclusion that the salinity reduced the vegetative growth and the yield of onion bulbs. Moisture treatment influenced both the diameter and weight of bulbs. The water consumption of the plants decreased with increassing soil salt concentration.

Acúmulo de macronutrientes por duas cultivares de cebola produzidas em sistema de semeadura direta

Economically, onion is the third more important vegetable in Brazil. As a consequence of the increasing by use of new hybrid varieties, the nutritional management of the crop needs to be adequately known. This research was carried out in São José do Rio Pardo, São Paulo State, Brazil, from March 7 to August 8, 2004. The objective was to quantify, under field conditions, the accumulation of macronutrients by onion cultivars established by direct sowing. The experimental design was in randomized blocks with three replicates. The cultivars studied were Optima and Superex. Samples were taken at 30, 50, 70, 90, 110, 130 and 150 days after sowing. With population of 354,000 plants ha -1 and productivity estimated in 64.8 t ha -1, 'Optima' extracted on 150 days after sowing: 78.77, 13.04, 75.77, 59.09, 11.70 and 24.38 kg ha -1 of N, P, K, Ca, Mg and S, respectively, and 'Superex', for the same plant population, and productivity at 72 t ha -1, 64.68, 10.33, 68.28, 65.58, 13.03 and 24.74 kg ha -1 of N, P, K, Ca, Mg and S, respectively. The Optima hybrid exported through its bulb about 49.17% of N, 60.60% of P, 61.16% of K, 41.15% of Ca, 43.56% of Mg, and 47.18 of S, the equivalent to 38.73, 7.90, 46.34, 24.32, 5.10 and 11.51 kg ha -1, respectively. The Superex hybrid exported through its bulb about 44.29% of N, 55.85% of P, 62.54% of K, 35.71% of Ca, 31.82% of Mg, and 48.80% of S, the equivalent to 28.65, 5.77, 42.70, 23.42, 4.15, and 12.07 kg ha -1, respectively.

Biosolid soil application: Toxicity tests under laboratory conditions

A large volume of generated sewage sludge makes its disposal a problem. The usage of sludge in agriculture is highlighted by a number of advantages. However, heavy metals and other toxic compounds may exercise harmful effects to soil organisms. This study evaluated the possible toxic effects of a biosolid sample, under laboratory conditions, for 30 days, using diplopods Rhinocricus padbergi and plants Allium cepa (onion) as test organisms. The data obtained demonstrated that the biosolid raw sample had genotoxic potential for Allium cepa root tip cells. In the diplopods exposed to biosolid sample, epithelium disorganization in the midgut and a reduction of the volume of the hepatic cells were observed after 7 days of exposure. After 30 days, the animals still showed a reduction of the volume of the hepatic cells, but in minor intensity. Allium cepa analysis showed genotoxicity, but this effect was reduced after 30 days of bioprocessing by diplopods. This study was important to know the effects as well as to determine how this waste could be applied concerning the soil living organisms and plants. © 2012 Cintya Ap. Christofoletti et al.

Clastogenicity of landfarming soil treated with sugar cane vinasse

The addition of nutrients and/or soil bulking agents is used in bioremediation to increase microbial activity in contaminated soils. For this purpose, some studies have assessed the effectiveness of vinasse in the bioremediation of soils contaminated with petroleum waste. The present study was aimed at investigating the clastogenic/aneugenic potential of landfarming soil from a petroleum refinery before and after addition of sugar cane vinasse using the Allium cepa bioassay. Our results show that the addition of sugar cane vinasse to landfarming soil potentiates the clastogenic effects of the latter probably due the release of metals that were previously adsorbed into the organic matter. These metals may have interacted synergistically with petroleum hydrocarbons present in the landfarming soil treated with sugar cane vinasse. We recommend further tests to monitor the effects of sugar cane vinasse on soils contaminated with organic wastes. © 2012 Springer Science+Business Media B.V.

A influência do uso e ocupação do solo na qualidade e genotoxicidade da água no reservatório de itupararanga, São Paulo, Brasil

The Brazilian reservoirs have been under great anthropogenic pressure due to continued population growth, which in turn places great pressures on the environment. Given this issue, this study aimed to analyze the influence of land use on the quality and genotoxicity of water in the Itupararanga reservoir, São Paulo, Brazil. Water and sediment samples were analyzed for their quality, genotoxicity and benthic diversity, as well as their interrelationship with the landscape. The reservoir was found to be eutrophic in most sampling stations, and genetic al terations were found in radicular cells of exposed Allium cepa in some sampling stations, besides a low diversity of benthic organisms. Among the variables that most contributed to the genetic alterations and water quality are the presence of riparian vegetation, the bare soil and urban occupation. With the results obtained in this study it was concluded that the quality of water and sediment at the Itupararanga reservoir is compromised, requiring emergency managements to ensure the sustainability of water resources.

Could contaminant induced mutations lead to a genetic diversity overestimation?

Contaminant driven genetic erosion reported through the inspection of selectable traits can be underestimated using neutral markers. This divergence was previously reported in the aquatic system of an abandoned pyrite mine. The most sensitive genotypes of the microcrustacean cladoceran Daphnia longispina were found to be lacking in the impacted reservoir near the entrance of the metal rich acid mine drainage (AMD). Since that divergence could be, at least partially, accounted for by mutagenicity and genotoxicity of the AMD, the present study aimed at providing such a characterization. The Allium cepa chromosomal aberration assay, using root meristematic cells, was carried out, by exposing seeds to 100, 10, 1, and 0.1 % of the local AMD. Chromosomal aberrations, cell division phases and cell death were quantified after the AMD exposure and after 24 and 48 h recovery periods. The AMD revealed to be mutagenic and genotoxic, even after diluting it to 1 and 0.1 %. Dilutions within this range were previously found to be below the lethality threshold and to elicit sublethal effects on reproduction of locally collected D. longispina clonal lineages Significant mutagenic effects (micronuclei and chromosomal breaks) were also found at 0.1 % AMD, supporting that exposure may induce permanent genetic alterations. Recovery tests showed that AMD genotoxic effects persisted after the exposure. © 2013 Springer Science+Business Media New York.

Avaliação do potencial genotóxico e mutagênico de águas e sedimentos do rio Guaecá, São Sebastião - SP, após impacto de oleoduto da região

Pós-graduação em Ciências Biológicas (Biologia Celular e Molecular) - IBRC

Avaliação da genotoxicidade e mutagenicidade das águas dos rios Jaguari, Atibaia e Piracicaba, na região de influência da refinaria de Paulínia - SP

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

Avaliação do potencial genotóxico e mutagênico de amostras de águas de recursos hídricos que recebem efluentes urbanos e industriais do pólo ceramista da cidade de Santa Gertrudes - SP

Pós-graduação em Ciências Biológicas (Biologia Celular e Molecular) - IBRC

Avaliação dos potenciais citotóxico, genotóxico e mutagênico das águas do Ribeirão Tatu, região de Limeira/SP, após o recebimento de efluentes urbanos

Pós-graduação em Ciências Biológicas (Biologia Celular e Molecular) - IBRC

Produtividade e qualidade da cebola em função de doses de enxofre

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Níveis de óleos essenciais na dieta de bovinos de corte terminados em confinamento: desempenho, características da carcaça e qualidade da carne

Pós-graduação em Zootecnia - FMVZ

Avaliação dos efeitos citotóxicos, genotóxicos e mutagênicos de 2 classes de agrotóxicos utilizados em cultura de cana-de-açúcar no Estado de São Paulo-Brasil

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

Avaliação da genotoxicidade e mutagenicidade de misturas comerciais de diesel e biodiesel puras e em simulações de vazamento em água e solo

Pós-graduação em Ciências Biológicas (Biologia Celular e Molecular) - IBRC

Investigação dos efeitos tóxicos do biossurfactante ramnolipídio e suas implicações quando usado na biorremediação de águas contaminadas por petróleo

Pós-graduação em Ciências Biológicas (Biologia Celular e Molecular) - IBRC