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Buffer solutions SMP, diluted (1+1) SMP, diluted Woodruff (1+2), calcium acetate 0.50 - 0.25 and 0.125 N estimate very well the lime requirement to bring to 6,40 the pH of several latosolic and podzolic soil samples incubated with calcium carbonate. Twelve equations were calculated by the method of least squares for the relationship between the pH of the soil-buffer suspension and the lime requirement to bring soil pH to 6.40 as determined by incubation.

The present research, considered exploratory by the Author, was dons in order to study leaf invertases of two coffee varieties, Geisha (SH1SH5) and Kent SH2SH5) inoculated with races III (v1v5) and XXIV (v2v4) of Hemileia vastatrix. The Geisha coffee is susceptible to race III and resistant to race XXIV, while Kent coffee has opposite reactions. In each pair of leaves, one was inoculated and the other was kept as control. Determinations of the invertases were made at 6 and 16 days after inoculation. The preliminary results showed that in the susceptible combinations there was no changes in the invertases, that were the same as in the healthy plants, with the maximum of activity at pH 4.5. In the resistant combinations, however, it was found an "acid invertase pH 4.0" on the 6th day after inoculations. This invertase was absent in both healthy and infected plants of the same varieties. The occurrence on the "acid invertase pH 4.0" is related to the decrease in the sucrose content of the leaves. The Author suggest three hipothesis that could explain a relation of this "acid invertase pH 4.0" with the coffee rust pathogenesis. These hipothesis, which could occur alone or simultaneously are: 1) The sucrose would be deviated to the formation of defense substances, such as phenols, phytoalexins and others. 2) The sucrose would be deviated to others parts of the plant, in 2l physiological process similar to that of the leaves in senescence. 3) There would be an increase in the respiration and metabolism of the infected tissues, with the implicit consumption of the stored energy.

The present work was carried out in order to study: a) the effect of omission and presence of the macronutrients on the growth of the plants; b) deficiency symptons of the macronutrients; c) the effect of the deficiency of each macronutrient on the chemical composition of the plants. Young sweet pepper plants of variety Avelar, were grown in pots containing pure quartz. Twice a day, they were irrigated by percolation with nutrient solution. The treatments were: complete solution and deficient solutions, in which each one of the macronutrient was omitted (HOAGLAND & ARNON, 1950). When the malnutrition symptons appeared, the plants were harvested and divided into: roots, inferior and superior stalks, inferior and superior leaves, new and old fruits. The dry matter was analysed chemically. Conclusions: 1) symptons of malnutrition are observed for N, P, K, Ca, Mg and S; 2) the symptons of deficiencies of K and Mg appear on the new leaves; 3) this variety is resistent to blossom-androt; 4) plants grown in N and Ca deficient solutions, show the largest reduction in development, compared to growth of normal plants; 5) the height of the plants is not affected by the omission of sulphur; 6) there's no reduction of the number of leaves on plants deficient in Mg; 7) the nutrient content expressed in porcentages in the ripened leaves of plants cultivated under normal nutrition conditions and under deficient conditions, expressed in Confidence Interval at 5% level, are:

The presente work, was carried out in order to study: a) the effect of omission and presence of the macronutrients on the growth of the plants; b) the amounts of macronutrients, absorbed during the growth of the plants; c) the sensibility to nutritional deficiences. Young sweet pepper plants of varieties Avelar and Ikeda were grown in pots containing pure quartz. Twice a day, they were irrigated by percolation with nutrient solution. The treatments were: complete solution and deficient solutions, in which each one of the macronutrients was omitted (HOAGLAND & ARNON, 1950). When the malnutrition symptoms appeared, the plants were harvested and their dry matter was analysed chemically. The absorption of macronutrients was studied with the plants of both varieties, cultivated under field conditions. Periodically, plants were harvested and analysed for N, P, K, Ca, Mg and S. Conclusions: 1 - both of the varieties are resistent to blossom-end rot; 2 - the variety Avelar has a greater demand in macronutrients, on the begining of fruitage, than the variety Ikeda; 3 - the variety Avelar is more sensibile to deficiencies of the macronutrients, than the variety Ikeda; 4 - the initial rate of growth of the sweet pepper during the first 75 days, in rather slow; 5 - new experiments are necessary to study times of application of N; 6 - there's no significant difference between the varieties, in the total nutrients absorbed on the end of the plant cycle; 7 - one ha of sweet plants (31,250) remove and export the following quantities in nutrients:

Symptoms of deficiencies of several macronutrients and binary combinations thereof were induced in the cotton plant. It was found that depending upon the particular combination the following picture developed: (a) individual symptoms are present according to the general pattern; (b) individual symptoms are present with a reversal of the general pattern with respect of distribution; (c) a combination of the individual symptoms shows up; (d) an individual symptom masks the other; (e) a different symptom develops. Chemical analysis of both upper and lower leaves has shown single and multiple effects depending upon the treatment considered.

Studies on soil moisture conditions for onion crop are important to state of São Paulo, primarily because in the regions where onion is cultivated, supplementar water is necessary. The experiment was conducted by using onion sets propagation, furrow irrigation method, and the standard gravimetric method for soil moisture content determination the treatments were differentiated by the allowed minimal water potential before each irrigation, as follow: -0,5; -1,0; -6,0 and -15,0 bars. The following conclusions were obtained under the climatic conditions observed during the experiment, soil, variety and methods used. a) positive responses to high soil moisture potentials (-0,5 bar) were observed in the data related to bulb weight, bulb and stalk diameter, leaf weight; b) maturity, number of leaves and incidence of Alternaria porri, Ellis, were not significantly by the treatments used.

This paper deals on the studies of the mannitol quantity necessary for the titration of boric acid with standardized solution of NaOH. The mannitol quantity is influenced by the pH of the end point of the titration. The results allowed to conclude that there is the possibility to reduce from 20.0 g to 5.0 g the quantity of mannitol necessary for titration of boron soluble in acid in fertilizers, provided the pH 8 be used as the end point of titration and proceeding the elimination of the ion NH+4 .

For the determination of boron soluble in acid, in fertilizers, 6,0 g of mannitol are sufficient. The influence of the ion NH4+ is eliminated by boiling the alkaly solution for 30 minutes. The sulfate ion affect the phosphate precipitation with Pb2+, beeing necessary 1 ml of 10% Pb (NO3)2 solution for each 1% of P2O5 of the sample. The method presents suitable precision and accuracy.

O presente trabalho descreve os estudos desenvolvidos com o objetivo de adaptar o método volumétrico de determinação do boro, solúvel em água, em fertilizantes, à técnica da titulação potenciométrica, usada na determinação do boro, solúvel em ácido, em fertilizantes. Os resultados mostraram que o método estudado é dotado de precisão e exatidão satisfatórias, comparáveis as do método volumétrico de determinação do boro, solúvel em água, em fertilizantes, baseado na titulação comum. O referido método possibilita simplificar, em parte, o aparelhamento de laboratório necessário para a determinação do boro, solúvel em água e solúvel em ácido, em fertilizantes.

The determinations of zinc and copper in fertilizers by atomic absorption spectrophotometry are not influenced by the concentration of HC1 in the extracts, in the range of 0,1 N to 0,5 N and neither by the anions phosphate, sulfate and nitrate in the same range of HC1 concentration. The methods are precise and accurate for the determinations of zinc and copper in fertilizers.

In the present work the effects of EDTA, potassium metabisulfite and potassium metabisulfite + tartaric acid were studied in the retention of ascorbic acid during freeze-drying and storage of West Indies cherry (Malpighia punicifolia (L.) and of strawberry (Flagaria vesca L.). The results and the statistical analysis showed that all treatments were significantly superior to the control. It was also observed that potassium metabisulfite + tartaric acid was slightly better than the other treatments but not statistically significant.

This paper deals with a work carried out in order to study the effect of the neutralization of the soil acidity caused by exchangeable Al³+. Portions of 1.000g of soils were well mixed with increasing amounts of CaCO3, put in vases and incubated for 45 days. The moist soils were kept at 40-50% for their field capacities. The following soils were tested: Sertãozinho and Monte Olimpo series from the county of Piracicaba and 2 and 18 unities from Rio das Pedras county. The treatments were as follows: Treatment Amounts of Ca applied as CaCO3. Control CaCO3 omitted 1 Stoichiometrically amounts related to the exchangeable Al³+ in 1.000g soil 2 Twice as applied in treatment 1 3 Three times the amount applied in the treatment 1. 4 Four times the amount applied in the treatment 1. After the incubation period the soils were dried at the air and ground. Further, the pH and exchangeable Al³+ and H+ were measured. The following conclusions can be drawn: a) The pH of the soils incresead when the amounts of CaC0(3) were incresead. b) In the soil of Monte Olimpo serie, the amount of CaCO3 applied in the treatment 1 was not sufficient to reduce the exchangeable A1+³ to a level non toxic to the plants.

Seedlings of (Phaseolus vulgaris L. cv 'Carioca') were treated, 7 days after germination, with gibberellins in the concentrations of 50, 500 and 1000 ppm and the check treatment, to verify the affect of the gibberellins on the morphology and productivity of the bean plant. The experiment was made under greenhouse conditions during year of 1972. The most effective treatment with the gibberellins were obtained with the concentrations of 500 and 50 ppm and excepting with the concentration of 500 ppm in which one a negative result was related with the length of leaves. There was an affective increase of elongation in the stem of the plants treated with the gibberellins. Significant differences related to the length of the internodes occurred during the first thirty-one days of growth and no significant differences were obtained after that period in the plants with gibberellins. It was also verified in all treated plants there was a little increase in the number of internodes and in the number of leaves. According with the number of flowers it was noted there was a tendency to increase the number of them at the concentrations of 500 and 50 ppm of gibberellins, however the production of the beans was not significant.

A method is described for impregnation undisturbed soil and clay materials with a clear and transparent plastic which polimerizes and hardens at room temperature. The impregnation is carried out under vacuum in a desiccator adapted to receive the impregnating solution (poliester resin Polylite T 213 and monomeric styrene, with methyl-ethyl-ketone peroxide as catalist). Thin sections of soil and clay materials were obtained with satisfactory results. The effectiveness of the impregnation was ascertained by the absence of sample desintegration, dissolution in water and cracking.

O presente trabalho teve por finalidade o estudo de cutans em dois perfis de solos pertencentes ao grande grupo Latossol Roxo (série Iracema, Município de Piracicaba, SP), e em dois perfis do grande grupo Terra Roxa Estruturada (Município de Botucatu, SP). Tal estudo baseou-se no exame das amostras dos perfis, em secções delgadas examinadas sob microscópio petrográfico. A análise de uma boa quantidade de lâminas revelou a presença de cutans iluviais nos horizantes B21 dos Lotossóis Roxos, no horizonte B1 e parte do B21 do perfil P3 (Terra Roxa Estruturada) e nos horizontes B21 e B22 do perfil P4 (Terra Roxa Estruturada).

Foram realizadas provas para conhecer a reação de 54 culturas e 34 ervas más ao nematóide Meloidogyne exigua. Nenhuma planta se revelou sensível ao parasito, apresentando-se atacadas apenas as variedades de Coffea arabica e um híbrido de C. arabica e C. excelsa.

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In this work were studied the correlation and the proportionality coefficients between the mesured evapotraspiration and Class A pan evaporation data, in a potato field-crop under three soil water regimes. The values obtained were significantly correlated, except when the soil moisture content reached a value corresponding to a capillary potential of about -2.0 bars from the stage of tuber growth to maturity. To practical purposes the evapotraspiration/Class A pan evaporation relationship were simplifield, so that only three average values, representatives of three stages of plant water requeriments, could be a useful tool to predict the irrigation requirements of the crop, even in relatively short periods.

1. Cotton plants were grown in water culture in the absence of each of six micronutrients (boron, copper iron, manganese, molybeenum and zinc) in turn. 2. The technique employed is described. 3. The effect of the treatments on growth, yeld and leaf composition is given. 4. The deficiency symptoms are described. 5. The effect of lack of micronutrients on leaf anatomy is also described. 6. The diagnostic volue of the data presented is discussed.

Hand and mechanized sugar-cane planting were compared to evaluate time and cost involved in this operation. An area of 6,400 m² was mechanically planted in 119.42 hours at a cost of Cr$ 371,99 requiring one operator whereas one man hand planting consumed 112.55 hours at a cost of Cr$ 342,06 for the same area. The statistical analysis of the data indicated no significant difference in relation to cost between the two procedures. The performance of mechanized planting was however of a better quality. A highly significant difference was found in favor of the sugar-cane planter in relation to cost and time of operation when equivalent operations required for planting sugar-cane were compared.