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An evaluation of the use of organic amandments to ameliorate aluminium toxicity and phosphorus deficiency in an acid soil.Mokolobate, Motlogeloa Salathiel. January 2000 (has links)
The effects of the additions of some commonly-available organic residues to an acid, P-deficient soil (typical of those used by small-scale farmers in KwaZulu-Natal) on soil pH, exchangeable and soil solution AI, P availability and maize yield response was investigated in a number of
laboratory and glasshouse experiments. The organic amendments used were ground-up grassveld residues, household compost, filter cake (a waste product from a sugar mill) and layer poultry manure. The soil used was a Hutton form (Farmingham series) (Rhodic Ferrasol, FAO).
In an initial laboratory study, addition of all of the organic residues, at rates equivalent to 10 and 20 Mg ha¯¹, raised soil pH significantly and as a result there was a marked reduction in exchangeable AI concentrations. The increase in pH and decrease in exchangeable AI was more
pronounced at the higher rate of addition and followed the order: poultry manure> filter cake> household compost> grass residues. The major mechanism responsible for the increase in pH was thought to differ depending upon the type of organic residue being considered. Whilst the
relatively high content ofCaC0₃ was probably the main mechanism in the case of poultry manure and filter cake, the proton consuming ability of humic material probably predominated for household compost and decarboxylation of organic acids during decomposition was probably the
main mechanism in the case of grass residues.
Additions of organic amendments also decreased concentrations of total AI (AIT) in soil solution
but the concentration of monomeric AI (AIMono) as estimated by pyrocatechol violet 60 sec. method, was unchanged or even increased. This latter effect was attributed to the high cation content of residues (particularly that of poultry manure) which increased soil salinity and exchangeable AI³⁺ was consequently displaced into soil solution.Additions of amendments also increased the Olsen-extractable P levels in the order: poultry
manure> filter cake> household compost> grass residues and their addition also decreased theP adsorption capacity ofsoils. Concentrations of exchangeable Ca, Mg and K, and Na in the case of poultry manure, were increased by additions of organic amendments. In a glasshouse experiment, the four organic residues were applied to soils at a rate equivalent to 20 Mg ha¯¹ with or without the addition of either lime (equivalent to 0, 5 or 10 Mg ha¯¹) or P (equivalent to 0, 10 or 50 kg ha¯¹). Lime applications to the control (unamended) treatment resulted in a marked reduction in exchangeable AI, AIT AIMono and in the proportion of AIT present as AIMono in soil solution. The addition of organic amendments increased soil pH and
reduced AIT and AIMono to low concentrations regardless of whether lime was applied or not. There was no yield response in maize to applied lime in any of the amended treatments. There was a yield increase in response to applied P in the control, household compost and grass residue treatments but none for the filter cake and poultry manure treatments. In agreement with this, Olsen-extractable P values in soils followed the order: poultry manure> filter cake> household compost> grass residues > control. It was concluded that the addition of organic amendments to acid soils is a practicable way of liming them and reducing the potential for Al toxicity and that it can also reduce fertilizer P requirements. This research now needs to be extended into the field situation. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2000.
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Use of organic amendments as ameliorants for soil acidity in laboratory and field experiments.Naramabuye, Fancois-Xavier. January 2004 (has links)
Laboratory studies and field trials were carried out to investigate the effect of
addition of some organic residues to acid soils on soil pH, exchangeable and
soluble AI, nutrient status, microbiological and biochemical indices and maize
response.
The organic wastes used in the first laboratory study included plant materials
(maize. sorghum, kikuyu grass, soybean, red clover residues and acacia
prunings), animal manures (kraal, pasture-fed and feedlot cattle manure, layer
and broiler poultry manure and pig manure), household compost, sewage sludge,
and filter cake. The poultry manure, pig manure and leguminous plant residues
had the highest content of basic cations while sewage sludge had the highest N
content. Poultry manure had very high values for proton consumption capacity,
CaC03 content and ash alkalinity. Proton consumption capacity, ash alkalinity,
total basic cation content and CaC03 content were closely correlated with one·
another. Soil pH was increased and exchangeable AI and total (AIT) and
monomeric (AIMono) AI in solution were decreased by addition of all the organic
wastes: the effect was greater at the higher rate of application. Strong
correlations were recorded between the rise in soil pH and proton consumption
capacity, ash alkalinity, CaC03content and basic cation content of the residues.
The major mechanisms responsible for the elevations in pH were suggested to
be the substantial CaC03content of poultry and pig manures, and filter cake, the
proton consumption capacity of humic material present in household compost
and manures and decarboxylation of organic acid anions during the
decomposition of plant residues and manures. It was proposed that ash alkalinity
is a suitable laboratory test for predicting the potential Iiming effect of organic
residues since it is strongly correlated with the rise in pH that occurs, it is
relatively simple to measure and the values reflect the initial content of organic
acid anions, humic materials and CaC03in the residues. A preliminary field experiment was set up to investigate the effectiveness of kraal
manure as a Iiming material in an acid soil (pHwater =4.1) at a site close to a Zulu
village. The experiment consisted of two rates of lime (L1 = 2.5 and L2 = 5.0 t ha1)
and two rates of kraal manure (K1 = 10 and K2 = 20 t ha-1
) which were
banded and incorporated in a 30 cm wide strip down the plant rows. Treatments
were arranged in a randomized block design with three replicates. A commercial
maize cultivar PAN 6710 and a traditional variety EMBO, used by the farmers in
the locality, were grown. Soils in the plant row were sampled at tasselling and at
harvest. The addition of kraal manure significantly raised soil pH and reduced
concentrations of exchangeable AI and those of both total and monomeric AI in
soil solution. Lime raised pH and the pH continued to increase between tasselling
and harvest. Maize yields for control, kraal manure (K1 and K2) and lime (L1 and
L2) for PAN 6710 were 2.5, 3.7, 5.1, 5.3 and 6.3 t ha-1
; respectively and for
EMBO they were 3.0, 5.4, 5.8, 5.9and 8.2 t ha-1
, respectively. These results
demonstrate the high yield potential of the traditional maize variety under small
scale farming conditions, and show that large yield increases can be obtained by
applying kraal manure.
The long-term effects (24 weeks) of incubation of organic wastes (soybean
residues, poultry, pig and kraal manures and sewage sludge) with an acid soil
were investigated in a laboratory study. After incubation for six weeks incubation,
soil pH was raised and exchangeable AI and Air and AIMono in soil solution were
decreased . by addition of the wastes. Soil pH generally declined and
exchangeable and soluble AI increased over the remainder of the incubation
period. The decline in pH was attributed mainly to nitrification of NH4+ originating
from mineralization of wastes-derived organic N. Addition of organic materials
generally resulted in a decrease in the proportion of solution Air present as
AIMono. That is, the effects of addition of organic materials was two-fold; an
increase in pH in the short term and complexation of AI by organic matter. Since
these effects occur simultaneously, it would be desirable to separate them. For this reason, short-term equilibration experiments (3 days) were conducted to
study the solubility of AI in aqueous solution or in an Oxisol when in equilibrium
,
with 3 manures (kraal, pig and poultry) at pH values of 4.0, 4.5, 5.0, 5.5, 6.0 and
6.5. Addition of manures tended to reduce the concentrations of total AI in
solution (AIT) in the lower pH range (Le. pH 4.0 and 4.5) but increased AIT
concentrations compared to the control, at higher pH values (Le. at pH 5.5 and
above). This was explained in terms of the complexing ability of both the solid
and solution phases. At lower pH, where AI is highly soluble, complexation by
added solid phase manure-organic matter results in a reduction of AI solubility.
However, at high pH, where AI solubility is limited, the most important
mechanism is complexation of AI by soluble organic matter and this increased AI
solubility. Additions of manure reduced the proportion of Air present in
monomeric form (AIMono). This effect was more pronounced in aqueous solution
but was also clearly evident above pH 5.0 in the Oxisol. This reflects the fact that
a large concentration of soluble C in solution can maintain relatively high
concentrations of complexed AI in solution but at the same time maintain low
concentrations of AIMono. It was concluded that formation of AI-organic matter
complexes caused by additions of organic manures can alter the solubility of AI
and reduce the amount of phytotoxic AIMono present in soil solution.
A second field trial was conducted to compare the effects of additions of kraal
manure, grass residues, lime and fertilizer (N-P-K) under field conditions, on soil
pH, AI solubility and maize response and, at the same time follow concomitant
changes in the size and activity of the soil microbial biomass and enzyme
activity. The greatest effects of kraal manure in increasing soil pH and
decreasing AI toxicity were recorded six weeks after planting whereas those of
lime and grass residues were recorded at harvest. Kraal manure and fertilizer
increased significantly AMBIC extractable P and exchangeable K and Zn. In addition, Kraal manure, and to a lesser extent lime significantly increased
exchangeable Ca and Mg.. Soils in the plant row in the grass residue treatments
had the highest microbial biomass C and microbial quotient,followed by kraal
manure, lime and controls. Basal respiration rates and arginine ammonification,
protease, aryl sulphatase, and acid phosphatase activity rates were significantly
increased by addition of all treatments and these increases tended to be
accentuated by fertilizer. Low values for metabolic quotient in the grass residue
treatments were associated with high values for microbial biomass C in these
treatments. The addition of all treatments tended to increase maize yields and, in
general, these yields were greater for the high rate of application of each
amendment. Yields for unfertilized kraal manure were markedly greater than
those for the unfertilized grass residue and lime treatments. This was attributed
to the ability of kraal manure to both increase pH and add nutrients to the soil. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2004.
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Improving acid sulfate soils for brackish water aquaculture ponds in South Sulawesi, IndonesiaMustafa, Akhmad, Biological, Earth & Environmental Sciences, Faculty of Science, UNSW January 2007 (has links)
Brackish water aquaculture is one of the largest coastal industries in Indonesia. This farming system involves the construction of ponds m coastal sediments. Many ponds in Indonesia have been abandoned due to past development of ponds in acid 8ulfate soils (ASS); these soils produce sulfuric acid through the oxidation of pyrite du ring and after the sediments have been excavated. The soils also contain elevated concentrations of metal such as iron and aluminium which are harmful to farmed fish and shrimp. Acidification of pond soil causes recurrent fish and shrimp mortalities, poor growth rate in fish and shrimp, soft shell syndrome in shrimp and low plankton densities, Pond maintenance costs in ASS are also significantly higher than non-ASS ponds. There are over 6.7 million ha of ASS In Indonesia of which 35% has been developed for brackish water aquaculture. This study developed and trialled methods of soil remediation to restore abandoned ASS-affected ponds. The main objective was to develop methods at remediation that were scientifically sound but also practical and inexpensive for farmers. The research involved characterising, in detail, the chemical and physical properties of ponds soil followed by laboratory-based experiments to improve soil properties. The results of laboratory trials were the basis for large-scale field experiments to test soil remediation strategies. The study showed that pond bottoms could be improved by forced oxidation, flooding and water exchange followed by Iiming and fertilising. Up to 500% increases in productivity were achieved by this method and soils conditions Improved significantly. A further twofold productivity increase was achieved by an integrated liming method in which lime is added to rebuilt or new dykes in layers. A juvenile shrimp production system was developed for ponds that were too severely degraded or costly to remediate. The research developed methods of preventing metal toxicity in Juvenile shrimp. The study showed that aquaculture ponds built in ASS could be remediated and returned to viable production systems. Importantly, the study has developed a more detailed understanding of chemical properties In ASS-affected ponds.
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Tissue-specific gene expression of two class III Arabidopsis peroxidases under aluminum stressLiu, Tianzhen. January 2010 (has links)
Thesis (M.Sc.)--University of Alberta, 2010. / A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science in Plant Biology, Department of Biological Sciences. Title from pdf file main screen (viewed on April 23, 2010). Includes bibliographical references.
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Aplicação de calcário e seus efeitos no sistema radicular, estado nutricional, produção e qualidade tecnológica de frutos de mangueirasAlmeida, Eliozéas Vicente de [UNESP] 02 July 2008 (has links) (PDF)
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almeida_ev_dr_ilha.pdf: 453428 bytes, checksum: 744e37c1df4e6218eba96b5abc328734 (MD5) / O presente trabalho teve por objetivo avaliar a aplicação de doses de calcário, em solo argiloso da região do cerrado, e seus resultados na produção, qualidade dos frutos e no estado nutricional das variedades de manga Haden e Keitt, enxertadas sobre o porta-enxerto coquinho, bem como avaliar o sistema radicular da mangueira ‘Haden’ em plantas com e sem calcário. O estudo foi realizado de março/2005 a fevereiro de 2008, em um Latossolo Vermelho distrófico, em um pomar implantado em 1992, espaçamento de 10 x 10 m, na Fazenda de Ensino, Pesquisa e Extensão da Faculdade de Engenharia/UNESP, Campus de Ilha Solteira, localizada no Município de Selvíria-MS. O delineamento experimental utlilizado foi em blocos casualizados, com 5 tratamentos, 4 repetições na ‘Haden’ e 3 na ‘keitt’, com 5 e 4 plantas por parcela, respectivamente, nas duas variedades. Os tratamentos foram compostos de doses crescentes de calcário, tomando-se como referência a dose calculada (3,1 t ha-1), como segue: T1 = testemunha, sem aplicação de calcário; T2 = metade da dose; T3 = a dose total; T4 = 1,5 vezes a dose e T5 = 2 vezes a dose calculada, correspondendo respectivamente a zero; 1,55; 3,10; 4,65 e 6,20 t ha-1. Foram avaliadas duas colheitas consecutivas de cada variedade (2006 e 2007 na mangueira ‘Haden’, 2007 e 2008 na ‘Keit’) e realizadas amostragens de folhas em quatro épocas diferentes. A calagem promoveu melhoria dos atributos químicos do solo (pH, Ca, Mg, SB, CTC, V (%) e H+Al), com efeitos significativos na produtividade, número de frutos planta, acidez titulável, sólidos solúveis e pH de frutos, havendo aumento nos teores foliares de Ca e Mg e diminuição nos teores de K, Fe, Mn e Zn. No sistema radicular promoveu aumento de 15,73% de raízes de absorção nas plantas que receberam calcário em relação à testemunha. As raízes de absorção de maior ocorrência foram aquelas com diâmetros menores do que 2 mm. / The present work aimed to evaluate the surface lime application, in the clay soil of the cerrado region, and to observe the effects in the production, fruits quality and nutrition state of two mangoes variety, Haden and Keitt, grafted on the variety Coquinho, as well to evaluate the distribution of the root system of the mangoes Haden variety in plants that received no calcareous and plants that received calcareous. The study was conducted between March 2005 and February 2008, in a dystrophic Red Latosol (Haplustox), in an orchard implanted in 1992, spacing of 10 x 10 m, at Experimental Station/UNESP/Ilha Solteira, located in Selvíria-MS. The experimental design was randomized block, with 5 treatments, 4 replicates in the ‘Haden’ and 3 in the ‘Keitt’, with 5 and 4 plants by parcel, respectively. The treatments were constituted by increasing doses of liming, taking as reference of the recommended dose (3.1 t of lime ha-1) as follows: T1 = zero; T2 = half of the recommended dose; T3 = a time the recommended dose; T4 = 1.5 times the recommended dose e T5 = 2 two times the recommended dose, corresponding to zero; 1.55; 3.10; 4.65 e 6.20 t ha-1, respectively. Two harvests of each variety (2006 e 2007 in the ‘Haden’, 2007 and 2008 in the ‘Keitt’) were evaluated and the leaves were sampled in four separate periods of time. Lime application promoted an improvement on the chemical properties of the soil (pH, Ca, Mg, SB, CTC, V (%) e H+Al), with significant effects on productivity, number of fruits by plants, soluble solid, acidity and pH of fruits, having increased in the tenors of Ca and Mg and reduced in the tenors of K, Fe, Mn and Zn on the leaves. In the root system, the plants that received lime presented 15.73% of the roots of absorption more than plants no lime. The roots of absorption of bigger occurrence had a smaller diameter by 2mm.
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Reaplicação superficial de calcário e gesso em sistema plantio direto: efeitos no solo e na sucessão de culturas / Surface reapplication of lime and gypsum in no-tillage system: effects on soil and crop successionBossolani, João WIlliam 23 February 2018 (has links)
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Previous issue date: 2018-02-23 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Em um sistema plantio direto em processo de estabilização, preconiza o não revolvimento do solo. Neste sentido o uso de gesso agrícola pode ser uma alternativa para viabilizar a aplicação do calcário em superfície sem que seja necessária sua incorporação. Dessa forma, o gesso entra como um insumo complementar ao uso do calcário. Em vista do exposto, o presente trabalho objetivou estudar o comportamento do calcário e/ou gesso reaplicados em superfície, e seus reflexos nos atributos químicos do solo e nas culturas do milho e soja em sucessão. O experimento está sendo desenvolvido desde o ano de 2011 em LATOSSOLO VERMELHO distrófico de textura argilosa, desde o ano de 2011, no qual se apresenta em delineamento em blocos ao acaso, em esquema de parcelas sub-subdivididas com quatro repetições. Como tratamentos nas parcelas, foi instalado o milho em dois sistemas de cultivo, sendo eles, solteiro e consorciado com Urochloa. Para as subparcelas foram utilizadas quatro doses de calcário (0; 2000; 4000 e 6000 kg ha-1) e quatro doses de gesso (0; 1500; 3000 e 4500 kg ha-1) distribuídas ao acaso nas sub-subparcelas. As aplicações foram em superfície manualmente em cada parcela e sendo realizadas as seguintes avaliações: características agronômicas, estado nutricional e produtividade de grãos das culturas do milho e soja e os atributos químicos do solo em diferentes profundidades (0,0 – 0,10; 0,10 – 0,20 e 0,20 – 0,40 m). O efeito residual das maiores doses de calcário reaplicados em 2014 proporciona maior produtividade na soja semeada 2 anos depois. Elevadas doses de calcário reduzem os teores de micronutrientes nas folhas de milho e soja. A produtividade de grãos de milho e soja é maior na associação de das doses de 4000 kg ha-1 de calcário com doses entre 1500 - 3000 kg ha-1. A reaplicação superficial de calcário e gesso combinados promovem redução da acidez e elevação dos teores de Ca e Mg no perfil do solo. A reaplicação de calcário associada com gesso contribui para que os efeitos da calagem superficial alcancem maiores profundidades. / In the process of stabilizing in a no-tillage system, the soil revolving must be minimized. In this sense the application of lime can be an alternative to enable the use of gypsum as an alternative to conditioner the subsurface soil layers in the short term, and it can be used as a complementary product to lime because of its greater solubility and mobility in the soil profile. Therefore, the aim of this experiment was to study the effect of lime and gypsum reapplied in surface and their impacts on maize crop under the sole and intercropped with soybean. The experiment is being developed in a dystrophic Red Latosol with clayey texture, since the year of 2011, and arranged in a randomized block designs, in split-split plots, with four replications. As treatments in the plots, the maize was installed in two cropping systems: sole and intercropped with Urochloa. For the subplots, were used four doses of lime (0; 2000; 4000 and 6000 kg ha-1) and four doses of gypsum (0; 1500; 3000 and 4500 kg ha-1) randomly distributed in the sub-subplots. The applications were manual and in surface in each plot, and being performed the following evaluations: agronomic characteristics, nutritional status and grains yield of maize and soybean and the chemical attributes of soil in three different depth (0,0 – 0,10; 0,10 – 0,20 e 0,20 – 0,40 m). The residual effect of the major gypsum doses reapplied in 2014 provided greater yield on the soybean sown two years after. Higher doses of gypsum reduced the micronutrient content in leaves of maize and soybean. The grain yield of maize and soybean is greater when associated with doses of 4000 kg ha-1 of gypsum and 1500 - 3000 kg ha-1 of lime. The combined surface reapplication of gypsum and lime promote acidity reduction and high Ca and Mg contents in the soil profile. The reapplication of gypsum associated with lime contributes to the superficial liming effects reach greater depths. / CNPq: 147116/2016-3
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Avaliação de eficiência relativa para a reatividade em silicatos /Deus, Angélica Cristina Fernandes, 1983. January 2010 (has links)
Orientador: Leonardo Theodoro Büll / Banca: Francisco Maximino Fernandes / Banca: Renato de Melo Prado / Resumo: A eficiência dos corretivos de acidez do solo, e, sua qualidade depende da taxa de reatividade (RE), e do poder de neutralização (PN), sendo esta eficiência indicada pelo poder relativo de neutralização total (PRNT). Para os silicatos existem poucos estudos que estabeleça taxas de reatividade para suas frações granulométricas e, portanto, utilizam-se as mesmas taxas de reatividade do calcário. Foram desenvolvidos três experimentos no período de julho/2008 a outubro/2009 em casa de vegetação na Faculdade de Ciências Agronômicas/UNESP - Botucatu-SP, com o objetivo de comparar valores de reatividade das frações granulométricas para materiais silicatados em três solos de diferentes classes texturais cultivados com plantas de alfafa. Utilizou-se seis materiais corretivos: escória, silicato de cálcio, silicato de cálcio e magnésio, wollastonita, calcário dolomítico e calcário calcítico os quais no experimento 1 e 2 foram separados em quatro frações granulométricas, peneiras: nº 10 (Ø = 2 mm), nº 20 (Ø = 0,84 mm), nº 50 (Ø = 0,30 mm) e fundo (Ø<0,30 mm), exceto a wollastonita que possui apenas a granulometria < 0,30 mm. Os tratamentos foram aplicados em três solos: Latossolo Vermelho distrófico, Nitossolo Vermelho eutrófico e Neossolo Quartzarênico. No 1° experimento aplicou-se quatro doses (1, 2, 4 e 8 t ha-1) afim de obter a curva de neutralização dos solos, para determinar a dose a ser aplicada de cada fração granulométrica para atingir o pH 5,5. O 2° experimento constou da aplicação das doses ecomendadas no primeiro experimento e com o valor de pH obtido aos 90 dias de incubação calculou-se a eficiência relativa de reatividade para cada fração granulométrica, tomando-se como referência o pH obtido com a aplicação do calcário dolomítico na peneira... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract : The efficiency and quality of materials for soil acidity correction are based on the reactivity rate (RR) and neutralization power (NP), and it is indicated by the effective calcium carbonate (ECC). Considering that there are few studies establishing reactivity rates of silicate particle-size fractions, lime values are used as reference. Three experiments were carried in the period July/2008 to October/2009 out in greenhouse in College of Agricultural Sciences, UNESP, Botucatu - SP, aiming to compare reactivity rates of silicate particle-size fractions in three soils with distinct textures cultivated with alfalfa plants. Slag, calcium silicate, calcium+magnesium silicate, wollastonite, dolomitic and calcitic lime were the materials evaluated. The first and second experiments consisted of four particlesize fractions obtained from each material, separated by the sieves no. 10 (Ø = 2 mm), no. 20 (Ø = 0.84 mm), no. 50 (Ø = 0.30 mm) and bottom (Ø < 0.30 mm), except that the wollastonite has the particle-size fraction < 0,30 mm. Treatments were applied in three soils: Oxisol, Hapludox and Quartzipsamment. In the first study, four doses were applied (1, 2, 4 and 8 t ha- 1) to obtain soil neutralization curve and thus determine which one was to be applied for each particle-size fraction to reach pH 5.5. The second study consisted of the application of the recommended doses from the first experiment. Then, with the pH values obtained 90 days after incubation, the relative efficiency of reactivity was calculated for each particle-size fraction based on the pH of dolomitic lime from the last sieve. Afterwards, RR and ECC were calculated. In the third study, the doses to increase soil base saturation up to 80% were calculated based on both the PRNT reported in the laboratory and in the experiment. Treatments were incubated... (Complete abstract click electronic access below) / Mestre
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Formas de aplicação e doses de calcário para alfafa implantada em área de plantio direto consolidadoToffolli, Leticia Cristina Bertusso 29 April 2013 (has links)
A alfafa (Medicago sativa L.) é uma forrageira leguminosa com alto potencial
produtivo, qualidade de forragem e variabilidade de utilização. Quando bem
manejada, é uma cultura capaz de fornecer forragem de qualidade e promover um
aumento na produtividade dos rebanhos. Para se expandir o uso desta forrageira no
país, torna-se necessário superar alguns entraves, como a falta de cultivares
adaptadas as diferentes condições edafoclimáticas e resistência ao pastejo. Este trabalho busca avaliar o efeito de diferentes doses de calcário combinadas a
distintas formas de aplicação sobre o desenvolvimento da cultura da alfafa em
sistema plantio direto. O experimento foi conduzido na Estação Experimental do
Instituto Agronômico do Paraná, localizada no Município de Pato Branco - PR. A
cultivar utilizada foi a Crioula. O delineamento experimental foi o de blocos ao acaso com quatro repetições em parcelas sub-sub divididas. Para as avaliações dos
atributos químicos do solo as parcelas constituíram-se das formas de aplicação de
calcário (aração+gradagem, subsolagem e superficial), as sub-parcelas pelas doses
de calcário (0, 2, 4, 6 e 8 t. ha-1) e as sub-sub parcelas pelas profundidades de solo
amostradas (0-5; 5-10; 10-20 e 20-30 cm). Para a avaliação dos teores de N, P, K,
Ca e Mg do tecido foliar da alfafa e taxa de acúmulo de MS diária as parcelas
constituíram-se pelos dias acumulados (56, 116, 144, 184, 220, 248, 286, 322, 353,
391, 432, 485, 530, 574 e 597 dias), as sub-parcelas pelas formas de aplicação de
calcário (aração+gradagem, subsolagem e superficial) e as sub-sub parcelas pelas
doses de calcário (0, 2, 4, 6 e 8 t. ha-1). A aplicação de calcário, mesmo que de
forma superficial, provocou aumentos de pH, dos teores de Ca e Mg e da saturação
por bases do solo, bem como, causou a diminuição dos teores de Al e da acidez
potencial do solo (H+Al), sendo estes efeitos percebidos nas camadas mais
inferiores do solo. Apenas em um período de avaliação de taxa de acúmulo de
matéria seca (220 dias acumulados) constatou-se influência da forma de aplicação
de calcário, sendo que nas 14 demais avaliações, não se constatou efeito deste
fator. Plantas cultivadas com 4 t. ha-1 de calcário nas parcelas sem incorporação
apresentaram teores de N do tecido foliar da alfafa superiores aos encontrados nas
demais plantas onde o calcário foi incorporado. Não há inconveniência da aplicação do calcário na superfície do solo sobre os teores foliares de Ca, K, Mg e P para
alfafa cultivada sob sistema de plantio direto. A prática de aração e gradagem ou de
subsolagem visando à incorporação de calcário no sistema de plantio direto
mostrou-se desnecessária. Em consequência disso, recomenda-se que, para a alfafa cultivada em sistema plantio direto estabilizado, a aplicação de calcário no
solo seja feita de forma superficial. / Alfalfa (Medicago sativa L.) is a forage legume with high yield potential, forage quality and variability of use. When well managed, is a culture able to provide quality forage and promote an increase in productivity of the herds. To enlarge the use of this forage in the country, it is necessary to overcome some obstacles, such as lack of suitable cultivars in our different environmental conditions and resistance to grazing. This study sought to determine the effect of different doses of lime combined with different forms of application to the development of culture in the alfalfa no-till system. The experiment was conducted at the Experimental Station of the Agronomic Institute of Paraná, located in Pato Branco - PR. The cultivar used was Creole. The experimental design was a randomized block design with four replications in split sub-divided. For the evaluations of soil chemical attributes the plots consisted of the forms of lime application (plowing + harrowing, subsoil and surface), the sub-plots for
limestone (0, 2, 4, 6 and 8 t. ha -1) and the sub-sub plots sampled for soil depths (0-5, 5-10, 10-20 and 20-30 cm). To assess the levels of N, P, K, Ca and Mg in alfalfa leaf tissue and accumulation rate of MS daily portions constituted by accumulated days (56, 116, 144, 184, 220, 248, 286, 322, 353, 391, 432, 485, 530, 574 and 597 days),
the sub-plots in the forms of lime application (plowing + disking, sub soiling and surface) and the sub-sub plots for limestone (0, 2, 4, 6 and 8 tonnes. ha-1). Liming, even if superficially, caused increases in pH, Ca and Mg and base saturation of the soil and caused the decrease in the levels of Al and potential soil acidity (H + Al ), and these perceived effects in lower layers of soil. Only in an evaluation period of accumulation rate of dry matter (220 cumulative days) revealed the influence of lime application form, and the 14 other reviews, we found no effect of this factor. Plants grown with 4 t. ha-1 of lime in the plots without incorporation showed concentration of the alfalfa leaf tissue than those found in other plants where the limestone was incorporated. No inconvenience of applying lime to the soil surface on the leaf Ca, K, Mg and P for alfalfa grown under no-tillage system. The practice of plowing or disking and sub soiling seeking the incorporation of lime in the no-tillage system proved to be unnecessary. As a result, it is recommended that for alfalfa grown in no-till system
stabilized, the application of lime in the soil is made lightly.
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Formas de aplicação e doses de calcário para alfafa implantada em área de plantio direto consolidadoToffolli, Leticia Cristina Bertusso 29 April 2013 (has links)
A alfafa (Medicago sativa L.) é uma forrageira leguminosa com alto potencial
produtivo, qualidade de forragem e variabilidade de utilização. Quando bem
manejada, é uma cultura capaz de fornecer forragem de qualidade e promover um
aumento na produtividade dos rebanhos. Para se expandir o uso desta forrageira no
país, torna-se necessário superar alguns entraves, como a falta de cultivares
adaptadas as diferentes condições edafoclimáticas e resistência ao pastejo. Este trabalho busca avaliar o efeito de diferentes doses de calcário combinadas a
distintas formas de aplicação sobre o desenvolvimento da cultura da alfafa em
sistema plantio direto. O experimento foi conduzido na Estação Experimental do
Instituto Agronômico do Paraná, localizada no Município de Pato Branco - PR. A
cultivar utilizada foi a Crioula. O delineamento experimental foi o de blocos ao acaso com quatro repetições em parcelas sub-sub divididas. Para as avaliações dos
atributos químicos do solo as parcelas constituíram-se das formas de aplicação de
calcário (aração+gradagem, subsolagem e superficial), as sub-parcelas pelas doses
de calcário (0, 2, 4, 6 e 8 t. ha-1) e as sub-sub parcelas pelas profundidades de solo
amostradas (0-5; 5-10; 10-20 e 20-30 cm). Para a avaliação dos teores de N, P, K,
Ca e Mg do tecido foliar da alfafa e taxa de acúmulo de MS diária as parcelas
constituíram-se pelos dias acumulados (56, 116, 144, 184, 220, 248, 286, 322, 353,
391, 432, 485, 530, 574 e 597 dias), as sub-parcelas pelas formas de aplicação de
calcário (aração+gradagem, subsolagem e superficial) e as sub-sub parcelas pelas
doses de calcário (0, 2, 4, 6 e 8 t. ha-1). A aplicação de calcário, mesmo que de
forma superficial, provocou aumentos de pH, dos teores de Ca e Mg e da saturação
por bases do solo, bem como, causou a diminuição dos teores de Al e da acidez
potencial do solo (H+Al), sendo estes efeitos percebidos nas camadas mais
inferiores do solo. Apenas em um período de avaliação de taxa de acúmulo de
matéria seca (220 dias acumulados) constatou-se influência da forma de aplicação
de calcário, sendo que nas 14 demais avaliações, não se constatou efeito deste
fator. Plantas cultivadas com 4 t. ha-1 de calcário nas parcelas sem incorporação
apresentaram teores de N do tecido foliar da alfafa superiores aos encontrados nas
demais plantas onde o calcário foi incorporado. Não há inconveniência da aplicação do calcário na superfície do solo sobre os teores foliares de Ca, K, Mg e P para
alfafa cultivada sob sistema de plantio direto. A prática de aração e gradagem ou de
subsolagem visando à incorporação de calcário no sistema de plantio direto
mostrou-se desnecessária. Em consequência disso, recomenda-se que, para a alfafa cultivada em sistema plantio direto estabilizado, a aplicação de calcário no
solo seja feita de forma superficial. / Alfalfa (Medicago sativa L.) is a forage legume with high yield potential, forage quality and variability of use. When well managed, is a culture able to provide quality forage and promote an increase in productivity of the herds. To enlarge the use of this forage in the country, it is necessary to overcome some obstacles, such as lack of suitable cultivars in our different environmental conditions and resistance to grazing. This study sought to determine the effect of different doses of lime combined with different forms of application to the development of culture in the alfalfa no-till system. The experiment was conducted at the Experimental Station of the Agronomic Institute of Paraná, located in Pato Branco - PR. The cultivar used was Creole. The experimental design was a randomized block design with four replications in split sub-divided. For the evaluations of soil chemical attributes the plots consisted of the forms of lime application (plowing + harrowing, subsoil and surface), the sub-plots for
limestone (0, 2, 4, 6 and 8 t. ha -1) and the sub-sub plots sampled for soil depths (0-5, 5-10, 10-20 and 20-30 cm). To assess the levels of N, P, K, Ca and Mg in alfalfa leaf tissue and accumulation rate of MS daily portions constituted by accumulated days (56, 116, 144, 184, 220, 248, 286, 322, 353, 391, 432, 485, 530, 574 and 597 days),
the sub-plots in the forms of lime application (plowing + disking, sub soiling and surface) and the sub-sub plots for limestone (0, 2, 4, 6 and 8 tonnes. ha-1). Liming, even if superficially, caused increases in pH, Ca and Mg and base saturation of the soil and caused the decrease in the levels of Al and potential soil acidity (H + Al ), and these perceived effects in lower layers of soil. Only in an evaluation period of accumulation rate of dry matter (220 cumulative days) revealed the influence of lime application form, and the 14 other reviews, we found no effect of this factor. Plants grown with 4 t. ha-1 of lime in the plots without incorporation showed concentration of the alfalfa leaf tissue than those found in other plants where the limestone was incorporated. No inconvenience of applying lime to the soil surface on the leaf Ca, K, Mg and P for alfalfa grown under no-tillage system. The practice of plowing or disking and sub soiling seeking the incorporation of lime in the no-tillage system proved to be unnecessary. As a result, it is recommended that for alfalfa grown in no-till system
stabilized, the application of lime in the soil is made lightly.
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Fisiologia e transcriptoma de milho cultivado em solo ácido / Physiology and transcriptome of maize grown on acid soilMattiello, Lucia 16 August 2018 (has links)
Orientadores: Marcelo Menossi Teixeira, Renato Atílio Jorge / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-16T10:26:16Z (GMT). No. of bitstreams: 1
Mattiello_Lucia_D.pdf: 1855407 bytes, checksum: 309c252e258389c8f81e79e8fba49e74 (MD5)
Previous issue date: 2010 / Resumo: A presença do alumínio (Al) em solos ácidos é o principal fator limitante da produtividade agrícola no Brasil e no mundo. A resposta desenvolvida pelas plantas contra o Al é complexa e a identificação de genes responsivos após a exposição ao íon através de técnicas de análise em larga escala, como microarrays, pode facilitar a sua compreensão. Este projeto possui como objetivo ampliar o conhecimento sobre a fisiologia e a regulação gênica de raízes e folhas utilizando genótipos contrastantes de milho (Cat100-6 (Al-tolerante) e S1587-17 (Al-sensível)) cultivadas em solo ácido com concentração fitotóxica de Al. As linhagens de milho Cat100-6 e S1587-17 foram cultivadas por um ou três dias em solo ácido (pH 4,1) ou solo corrigido com Ca(OH)2 (pH 5,5). O genótipo S1587-17 apresentou uma maior inibição do crescimento radicular, resultado este altamente correlacionado com a acumulação de Al nos ápices radiculares e deposição de calose. Os dados fisiológicos confirmam a discriminação entre as duas linhagens em solo, abrindo perspectivas para entender pela primeira vez a base molecular das alterações das plantas em condições próximas à realidade de campo. O transcriptoma de raízes possibilitou a identificação possíveis candidatos a tolerância ao Al. Adicionalmente, com um experimento de hidroponia separamos as variáveis pH e presença de Al, ambas condições diferenciais do tratamento com solo. Identificamos, entre os candidatos, genes responsivos pela presença do Al e não pela acidez delimitando assim os genes com possíveis papéis na tolerância ao Al presente no solo ácido a apenas três: retinol desidrogenase, um fator de transcrição WRKY e uma proteína desconhecida. Esses resultados permitem concluir que o cultivo em solo é diferencial em relação à hidroponia, e outros fatores que apenas presentes no substrato solo podem provocar a indução de alguns genes. Diversas vias metabólicas são afetadas na linhagem sensível pelo tratamento em solo ácido e podem estar envolvidas na inibição radicular como a produção de lignina, celulose e calose e a síntese de etileno e auxina. O mapeamento nos cromossomos dos genes identificados pelo experimento de microarray das raízes de milho permitiu a identificação de genes localizados dentro de QTLs de milho previamente descritos na literatura como responsáveis pelo fenótipo tolerante. Diante esse resultado, podemos especular o papel de genes como uma proteína ligadora de RNA, uma inibidora de proteases e ciclinas na tolerância ao Al contido no solo ácido. Pela primeira vez na literatura, o transcriptoma de folhas coletadas após três dias de cultivo em solo ácido ou solo corrigido foi obtido com o uso de microarrays da Affymetrix. Essa análise indicou profundas alterações na Cat100-6, em contraposição à ausência de alteração significativa nas folhas na S1587-17. Genes referentes à fotossíntese e a fotorrespiração foram regulados negativamente pelo tratamento em solo ácido no genótipo tolerante. Contudo, o ciclo do ácido cítrico está ativado indicando uma putativa participação da produção de ácidos orgânicos nas folhas na resposta ao Al / Abstract: The presence of aluminum (Al) is the main factor limiting crops yield in Brazil and worldwide. The plant responses developed against this ion are complex and the identification of responsive genes after exposure to the ion with the use of a large scale technique, such as microarrays, can facilitate its comprehension. This project aimed to amplify the knowledge about physiology and gene expression regulation of roots and leaves associated towards Al resistance using contrasting maize genotypes (Cat100-6 (Al-tolerant) and S1587-17 (Al-sensitive) cultivated in acid soil containing phytotoxic concentrations of Al. Maize lines Cat100-6 and S1587-17 were cultivated for one or three days in acid soil (pH 4,1) or limed soil with Ca(OH)2 (pH 5,5). The genotype S1587-17 presented a higher root growth inhibition, which is highly correlated with Al accumulation in the root apexes and callose deposition. The physiological data confirms the discrimination of the two maize lines cultivated in soil, opening perspective to understand for the first time the molecular bases of alterations in plants on a closer condition to the field. Transcriptome from roots made possible the identification of possible tolerance candidates and genes constitutively expressed genes in the tolerant line. Additionally, throw a hydroponic experiment we splited the variables pH and Al presence, both differential conditions between soil treatments. It was possible to identify, among the candidates, genes responsive in the presence of Al in acid soil rather than acidity limiting genes with a possible roles in Al present in the acid soil tolerance to only three: retinol dehydrogenase, the transcription factor WRKY and an unknown protein. These results allow the conclusion that the soil culture is different in relation to hydropony, and other factors present only in soil substrate could provoke the induction of some genes. Several metabolic pathways were affected in the sensitive line after acid soil growth and could be involved on root growth inhibition such as lignin, cellulose and callose production and ethylene and auxin synthesis. The mapping of the identified genes through the microarray experiments into the chromosomes allowed the identification of genes localized into maize QTLs previously reported in the literature as responsible for the tolerant phenotype. Facing these results, we can speculate the role of these genes such as a RNA binding protein, a protease inhibitor, and cyclines in the Al present in the acid soil tolerance. For the first time in literature, the transcriptome of leaves collected after three days in culture with acid soil or limed soil with the Affymetrix microarrays. This analysis indicated great alterations in Cat100-6, meanwhile S1587-17 showed no significative alteration. Genes related to photosynthesis and photorespiration were down-regulated due acid soil treatment in the tolerant genotype. However, citric acid cycle was activated indicating the putative partitipation of organic acids produced in the leaves in thr Al response / Doutorado / Genetica Vegetal e Melhoramento / Doutor em Genetica e Biologia Molecular
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