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Copper in soils, both total and soluble in several extracting solutions, was determined by the sodium diethyldithiocarbamate colorimetric method. For the determination of total copper, 250 mg samples of 5 differents soils from the state of São Paulo, were attacked with HC1O4, HF and HNO3 mixture. The amounts of total copper found varied from 23 to 126 ppm. The soluble copper was extracted by shaking the soils with 0,05 and 0.10 N HCl, 1% disodium EDTA, and 0,10 N CH3COOH solutions. For the extraction with HCl solutions, 2.5 and 5.0 g of soil were shaken with 50 ml of HCl solutions for 10, 15 and 30 minutes. The amounts of copper found were from 0.5 to 14.6 ppm for the 0.10N HC1 and from 0.3 to 10.2 ppm for the 0.05 N HCl solutions. The extrations with the disodium EDTA and CH3COOH solutions, were made by shaking 5.0 g of soil with 50 ml of extracting solution for 10, 15 and 30 minutes. The amounts of soluble copper were from 0.8 to 15.0 ppm for the disodium. EDTA solution, and from 0.0 to 0.5 ppm for the CH3COOH solution.

Young coffee plants were grown in nutrient solution from which the following elements were omitted, singly or in several combinations: nitrogen, potassium, boron and zinc. The choice of these elements was basee on the high frequency of occurrence of their deficiencies under field conditions in Brazil. The effect of single or multiple deficiencies was studied under several aspects, namely: growth, visual symptons, mineral composition. The following conclusions can be drawn: (1) symptons of deficiency of nitrogen, potassium, boron and zinc can be identified even when occurring simultaneously; (2) the concentration of nitrogen, potassium, boron and zinc is markedly influenced by their supply in the substrate, as well as by the concentration of other elements in the medium; (3) cases of multiple deficiency should be taken into consideration when interpreting results of leaf analysis.

Carrot seeds (Daucus carota L.var. Shin Kuroda) were sowed in pots containing quartz. After seeds germination the seedlings were irrigated during 35 days with complete nutrient solution. Further groups of plants were exposed to the following treatments: complete solution, -N, -P, -Ca, -Mg and -S. Deficiency symptoms were described, with exception for K. Plants were harvested and divided in leaves and roots. Chemical analysis for the macronutrients were run of the parts. The percentage of the macronutrients in the dry matter of the leaves of healthy plants were: N-2.10, P-0.20, Ca-2.50, S-0.43. Plants showing deficiency symptoms in the leaves presented the following values: N-0.79, P-0.09, Ca-0.77, Mg-0.05 and S-0.12.

Foram estudados quatro métodos de avaliação da exigência de calcário de diversos solos, pertencendo a maioria a séries bem caracterizadas do Município de Piracicaba, Estado de São Paulo. Serviu como referência o método de incubação, segundo o qual 20 amostras foram tratadas com cinco doses de carbonato de cálcio puro, perfazendo um total de 100 amostras. Verificou-se que o método baseado na extração de hidrogênio ou prótons dos diversos componentes da acidez do solo, com solução 1 N de acetato de cálcio, pH = 7,0, é o mais simples, rápido e sensível, e forneceu um coeficiente de correlação r = 0,92, quando comparado com o método de incubação. O método que emprega a solução tampão SMP, e que também extrai hidrogênio ou prótons dos diversos componentes da acidez do solo, também foi eficiente (r = 0,90). O método baseado na elevação da saturação em bases a 85%, calculando-se a capacidade de troca de cátions CTC ou t, levando-se em conta o hidrogênio extraído com solução 1 N de acetato de cálcio, pH = 7,0, apresentou o coeficiente de correlação mais elevado (r = 0,96). Finalmente, o método baseado na extração do alumínio trocável com solução 1 N de KCl, relacionado à exigência de calcário para atingir o pH = 5,7, determinada por incubação, apresentou um coeficiente de correlação r = 0,72.

A procedure is described for bringing into solution the total content of copper, iron, aluminon, manganese and phosphorus, followed by the colorimetric determination of those ele ments. The procedure consists of heating 250 or 500 miligrams of the prepared soil samples with 1.5 to 3.0 ml of perchloric acid and 5.0 to 8.0 ml of hydrofluoric acid. Copper was determined by the diethyldithiocarhamat method; iron, by the 1,10-phenanthrolim method; aluminum,by the aluminon; manganese, by the permanganate; and phosphorus by the molybdenum blue mehtod, using ascorbic acid as reductor.

In this paper, the authors have studied, under laboratory conditions, the relations between several species of Aspergillus and Penicillium genders and three insoluble phosphates, having determined quantitatively both the portion rendered soluble and the one not decomposed by the fungi. From the results obtained the following conclusions were drawn: 1. All the studied strains showed high capacity to render soluble insoluble phosphates in petri dishes tests. Nevertheless, when quantitatively evaluated, only A. niger was able to render soluble an appreciable amount of insoluble phosphates. 2. The analysis of the data obtained with the Penicillium spp strain, showed that both increased significantly the levels of soluble phosphate for the aluminum phosphate treatment, compared with their sterile homologues; the levels of soluble phosphate in the checks decreased significantly and, the treatments with iron phosphate had their levels not altered significantly. On the other hand, in the treatments with "Araxá rock phosphate" the level of soluble phosphate did not change appreciably for the 4 RAIZ III strain and, decreased significantly for the 8 RIZ III strain. 3. The Aspergillus sp strain, reacted differently compared to the other fungi, that is, all treatments had their soluble phosphate levels decreased. 4. The indirect evaluation of available phosphorus in the soil, using A. niger and other fungi, shows inaccurate values due to the adherence of insoluble phosphate particles to the micellia.

In this paper the author presents a new manner of expressing the "L" LARSEN's (1952) value. It refers, also, to SO-KOLOV's (1958) equation and to the technic of inverse isotopic dilution.

This paper describes a direct method for determining organic soil sulfur. By the proposed method the soil is ashed in an eletric tube-furnace at 800°C in a stream of oxygen and the escaping gases were absorbed by oxygen peroxide solution. After the ashing the excess of oxygen peroxide is eliminated by ebullition, and the resulting sulfate is determined by the colorimetric method based on the reaction with barium chloranilate, and the absorbance was determined at 308 milimicrons. The results obtained allowed to conclude that the tech nique proposed is good and the accuracy satisfactory.

Um experimento sobre adubação de milho (Zea maysL.), variedades "Agroceres - 13", foi conduzido no Município de Oliveira, Estado de Minas Gerais, com a finalidade de se estudar o efeito de adubos nitrogenado, fosfatado e potássico sobre a produção desse importante cereal. Os resultados obtidos a partir de um ensaio fatorial 2³ mostraram que a adubação nitrogenada foi a que proporcionou maior produção e renda líquida. Para a adubação fosfatada, houve um pequeno aumento de produção. Não houve resposta ao potássio.

This paper deals with the water balance of Guarea trichilioides L., a meliaceous tree, native in the tropical America. Transpiration was measured by the method of rapid weighing of detached leaflets. Determinations of transpiration values showed that G. trichilioides did'nt restrict transpiration in the more hot hours of the day. Relative transpiration was higher than that of the trees of the rain tropical forest. Relative cuticular transpiration was low, as in most trees of the rain forest, and lower than that of several plants of the cerrados (brazilian savannae). Hydroactive movement of the stomata was relatively rapid in the initial phasis, becoming however, very slow, before attaining the values of the cuticular transpiration. The saturation deficit was always low, as in the rain tropical forest trees. From the study of the water balance and leaf structure, we can realize that Guapea trichilioides is a tree of the tropical forest unadapted to support conditions of intense drought.

The solubility of three samples of pure tricalcium phosphate and of one sample of bone meal in 2% citric acid solution, in the proportion of 1:200, is almost total, that is,their content in P2O5. By other side, the rock phosphates present a partial solubility in 200 ml of 2% citric acid. The number of milliequivalents of hydrogen in 200 ml of 2% citric acid solution is almost the doble of the number required for the solubilization of 1 gram of phosphate or calcium fluophosphate. On the basis of the data obtained from this study it is possible to stablish the proportion of 1:200 for the extraction of P2O5 of rock phosphate and to interpret the extracted P2O5 as equivalent to tricalcium phosphate (TFE).

The following items concerning Mononchid nematodes are dealt with in this paper: a) A historical review of the family Mononchidae from the establishment of the type genus Mononchus Bastian, 1865, to our present days. Sixteen genera are recognized in the family. Morphology, based particularly on species found in Brazil. c) A review of the role assumed by the Mononchidae as members of the biotic complex of soil, with observations on behavior of species found in Brazil. Two Mononchus papillatus females showed in the gut larvae apparently belonging to its own species, thus confirming occurrence of cannibalism. d) A description of a new species (Sporonchulus paucidentatus n. sp.) and redescriptions of a few other forms that the author found in the Country for the first time. These were: Sporonchulus dentatus, Mononchus papillatus, Mylonchulus incurvus and Mylonohulus sigmaturus. A species closely resembling M. incurvus is described and provisionaly named Mylonchulus sp. Diagnosis of S. paucidentatus n. sp. - A Sporonchulus having the dimensions cited in the description, an arcuated tail, and stoma armed with 4 subventral denticles only. e) A key for separating the genera known to occur in Brazil. f) A list of the species of Mononchidae found in Brazil, with citation of the pertinent literature and observations on distribution, morphology, habits, etc. g) Keys for separating the species of the genera found in the Country.

This paper is the first of several papers about the studies of neutralization of sugar cane juice, after treatment with SO2 in the cane sugar fabrication. The present work reports a study about the chelatometric method for the determination of total calcium oxide and magnesium oxide of lime and the available lime. The proposed method (by EDTA titration) for determining available lime was compared with the method based on sulfuric acid titration, with good agreement. The results showed that the chelatometric method is rapid and affords good precision. For the study about the neutralization of sugar cane juice, after treatment with SO2, were employed samples of lime containing several per cent of available lime. The quantities of lime to be added, to one liter of treated juice, was calculated based in the total calcium oxide of the lime. The solid samples of lime were added to the juice slowly and the material shaken intermittently during the period of fifteen minutes after the addition of lime. The pH was determined both 15 minutes and 2 1/2 hours after the addition of lime. Them it was brought to ebullition, cooled at room temperature and the pH was again determined. The results permit to conclude that the samples containing small amounts of available lime showed the poorest neutralization. Even with samples containing high percentage of available lime it was not possible to obtain a juice with pH 7,0 after the treatment, probably due to the presence of carbonates in the samples of lime. This study showed that the principal characteristic of lime to be employed in the juice neutralization is the available lime.

The object of this work is to study the crystaliza -tion patterns of copper chlorids (CuCl2.2H(2)0) as influenced by extract of coffee seeds (Coffea arábica L.), variety Mundo Novo. Investigation and description are made for 16 different concentrations of the water-copper chloride-extract system, with 3 replications. The best crystallization patterns were obtained by using the filtered-mixture technique. The results indicate that concentrations between 0,5 and 1,0 g per plate of copper chloride and between 0,05 and 0,075 g per plate of extract can be recommended.

The objective of this work is to establish a colorimetric method for the quantitative determination of montmorillonite. It is based on reaction of this clay mineral with benzidine, because the colouring complex follows the law of Lambert Beer in the interval from 7,35 to 36,75 ug of montmorillonite/ ml. Various concentrations of this mineral were treated with 1,0 ml of an aqueous solution of benzidine, and the absorbance of the complex was readen after 48 hours with a filter number 60 in a "Klett-Summerson" colorimeter. With these data it was made an equacion reporting the concentration against the absorbance, what is: X - 5L - 14,7 (L is absorbance and X is ug of montmorillonite). It was also tested the influence of other minerals as quartz and kaollinite. The conclusion was that they increase the absorbance. In this test two new equacions were obtained: X = 4,17L - 30,04 for the misture of montmorillonite, quartz and kaollinite and X = 4,76L - 60,33 for the misture of montmorillonite and quartz. In the misture where the three minerals are present the increases are higher than when only quartz was present.

O presente trabalho teve por finalidade o estudo morfológico, físico, químico e taxonómico da serie Piracicaba. Foram coletados, na área de ocorrência desta serie, quatro perfis designados por perfis P1, P2, P3 e P4. As amostras dos horizontes foram colhidas a partir da superfície do solo até a rocha, sendo realizadas nestas camadas análises mecânica e química. A fração argila foi separada por sedimentação, sendo posteriormente dividida em duas subfrações: 2 a 0,2 u e menor que 0,2 u, argila grossa e fina, respectivamente. Os dados referentes à analise mecânica revelaram que a variação média extrema do horizonte B2 é de 27,05 ± 0,89 e 34,95 ± 0,88%. Estes solos foram classificados como Typic Tropudalfs e nao se enquadram no conceito modal do Podzolico Vermelho-Amarelo variação Piracicaba da COMISSÃO DE SOLOS (2).

This paper deals with the estimation of the heritability of weight at the age of 18 months of heifers of the Canchim breed, which is a 5/3 Charolais x 3/8 Zebu crossbred. It evaluates also the bulls and cows, through the heritage transmitted to their offspring. The study was carried out with the 18-month weights of 252 heifers, sons and daughters of 15 sires and 94 cows, adjusted for sex, and for season and order of delivery. The adjustment was carried out with the aid of the mathematical model with s i (i = 1,2) referring to sex, e j (j = 1, 2, 3, 4) to season, and Pk (k = 1, 2, 3, 4, 5) to parturition. With the adjusted weights y ijkr obtained by the formula an analysis of variance was carried out, following the incomplete randomised model, with sires as blocks and cows as treatments using the theory developed by PIMENTEL GOMES (1967, 1968, 1970), with the following results. With the variance components E, Dand S thus obtained the estimates hI; 1 and hI; 2 of the coefficients of heritability were calculated, by formulas having been obtained the following results: hI; 1 = 0.6325 ± 0.28, hI; 2 = 0.6292 ± 0.28. This study permitted also the evaluation of the bulls and cows of the herd.

Na presente nota prévia, são relatados os resultados de efeito de doses crescentes (0,2 - 0,8 mg de herb. p.a.) de diuron sobre o poder nitrificante em solo da serie "Luiz de Queiroz" e arenito, de Botucatu. Os resultados ate o presente momento indicam que o herbicida não influi no poder de nitrificante destes solos.

Gladiulus corms nº 3 (Gladiolus communis var. Itapetininga) were germinated in pots containing 7 kg of quertz. After germination the plants were irrigated several times a day with HOAGLAND & ARNON (1950) complete solution. Fifteen days after germination plant were harvested every ten days and subdivided in: aerial part, mother corms, daughter corm and bulbils. The different parts of the plants were weight and analysed for nitrogen, phosphorus, potassium, calcium, magnesium, sulphur, boron, copper, iron, manganese and zinco. It was observed that gladiulus plant show a fast growth period until fifty-five days. After this period is shows only increase in weight until seventy five days. A gladiulus plant at final cicle presents 362.6 mg of N; 78.4 mg of P; 536.4 mg of K;73.4 mg of Ca; 27.9 mg of Mg; 35.9 mg of S; 1,019.4 of B; 94.7 ug of Cu; 1,655.6 ug of Fe; 914.6 ug of Mn and 272.3 ug of Zn.

Onion plants (Allium cepa L. var. Baia Piriforme Precoce Piracicaba), 70 days, old were grown in pots containing 7 kg of quartz sand. Twice a day they were irrigated by percolation with complete solution. Every 15 days from the 70 th day plants were harvested divided into aerial part and bulb. The parts were weighed and analysed for N, P, K, Ca, Mg and S. Data obtained allowed for the following main conclusion: a) The initial rate of growth of the onion during the first 85 days is rather slow b) The uptake of nutrients is small until the 85 days, increasing at the 145 days. c) The following amounts of nutrients in kg/ha were absorved by a population of 166,666 plants with a production of 36,700 kg of onion: N 132.8 P 21.9 K 177.0 Ca 15.9 Mg 17.8 S 33.8