RCAAP Repository

A manutenção de um balanço hídrico favorável à planta é uma condição reconhecidamente necessária para assegurar a seqüência das reações metabólicas que se desenvolvem nas células vegetais. Os deficits de água¹ nas plantas poderiam ser quantitativamente avaliados a partir de determinações do teor ou do estado de energia da água dos tecidos. Neste trabalho, o potencial osmótico das hastes e folhas, o potencial da água da folha e as relações entre este e o teor relativo de água da folha foram determinados em plantas de batata (Solanum tuberosum L.) adequadamente supridas com água do solo, em condições de campo. Os resultados revelaram que os potenciais determinados variaram durante o ciclo fenológico. Assim, o potencial da água da folha foi sendo reduzido com o desenvolvimento das plantas. Após o completo desenvolvimento vegetativo, não foi possível identificar qualquer tendência definida, crescente ou decrescente. Esta variação modificou as relações entre o potencial e o teor relativo de água da folha, de tal maneira, que o potencial associado a um determinado teor relativo de água, foi sendo reduzido a medida que as plantas se desenvolveram. A par destes resultados, pode-se concluir que o potencial da água da folha não parece ser um indicador seguro da existência de déficits fisiológicos de água na planta. O conhecimento do teor relativo de água, associado ao potencial, poderia contribuir decisivamente para fornecer uma avaliação mais precisa da condição da água nos tecidos vegetais.

This paper deals with the results of experiments designed to study the nature of the effect of phosphate (P) ion on the absorption of zinc (Zn) by plants. Due to the conflicting results found in the literature the following working hypothesis were raised and checked: a. R decreases Zn levels in the top by interfering with its uptake at the root level; b. decreases Zn uptake by roots due to preciptation at their surface; c. R decreases Zn content in the top by a negative effect on the upward movement of the absorbed element; d. R decreases Zn uptake in soil conditions by rendering it unavailable. Experiments with excised roots and whole plants were conducted using barley as an indicator. Experiments with excised roots and whole plants were carried out at there Zn concentraions (5 x 10-6M, 5 x 10-5M, and 5 x 10-4M) a pH 5.0 6.0 and 7.0. In the farmer trials 0,5 g of roots excised from 7 day old seedlings were used during an uptake period of 30 minutes; phosphates of Na, K, NH4, Ca and Mg were used at the concentrations of 10-5M, 10-4M and 5 x 10-3M. In order to better define a possible role of the accompanying cation same experiments were repeated replacing the phosphate by the chloride ion. The effect of the internal R status of the plant both of he upake and translocation was studied using respectively roots excised from plants previously grown in phosphate solutions (10-4M, 10-3M, and 5 x 10-3M) and whole plants (0, 10-4M, 10-3M and 10-2M). The influence of phosphatic fertilization was assessed by supplying varying rates of R (0, 200 and 400 ppm) plus other macro and micronutrients in standard amounts to three soil types (Regosol, Reed yellow Latosol sand phase and Reed Latosol) in the presence and in the abscence of lime. In all experiments 65Zn was used as tracer. The main conclusions were the following: a. all salts used in soilless experiments reduced Zn uptake by non competitive inhibition; b. the size of the effect is pH dependent; c. inhibition is greater when either R or Cl are accompanied divalent cation; d. effect is higher than Cl's; e. Precipitation of Zn by R in soilltss mtdium may take place depending upon concentration and pH, the phenomenon occurring either in them edium it self or at the surface; f. previous phosphatic nutrition did not decrease Zn uptake having however, slight, negative effect on translocation when high levels of the anion were used in the pretreament combined with low concentrations of the micronutrient during the experimental period; g. phosphatic fertilization and liming decreased Zn concentration in the olant having no lowering effect on its availability in the soil as revealed by a chemical method, the first variable actually increasing absorptionas determined by the "L" values thereof.

The fatty acid composition of different kinds of edible vegetable oils (corn, soybean, olive, cottonseed, peanut and sunflower seed) and animal fats (butter and lard) was determined by gas liquid chromatography. The sunflower seed oil presented the highest yield of unsaturated acids (86.10%) followed by the soybean oil (84.15%), while Cottonseed oil showed the highest saturation (24.23%). Butterfat revealed great number of fatty acids (32) from 4 to 22 including several fatty acids with odd number of carbon atoms.

The nitrogen content of 28 samples of green coffe (Coffea arabica L.c. v. Mundo Novo) of four types of beverage, i. e. Soft, Hard, Rioy and Rio, was determined. The figures varied from 2.53% (mean value) for samples of Hard and Rio, 2.55% for Solft and 2.59% for Rioy beverages, dry weight. It were not found statiscally significant diferences between samples of diferent kinds of beverage and so it was not possible to stablish a correlation between the content of this component and the type of beverage.

The content and properties of the lipid fraction and fatty acid compositon of the oil in 28 samples of green coffee (Coffea arabica L., c. v. Mundo Novo) of four types of beverage, i.e., Soft, Hard, Rioy and Rio, were determined. The ether extract content was higher in coffees of better beverages, but significant difference was found only for Hard ones. It were not found differences in the fatty acid composition and in the chemical properties of the ether extract: saponification, iodine and acid numbers; none of them showed significance. It was concluded that these components and properties can not be used to characterize the type of beverage in green coffee, significance. It was concluded that these conmponents and properties can not be used to characterize the type of beverage in green coffee.

In the present work the organic and mineral composition of 14 varietis of beans (Phaseolus vulgaris L.) commonly found in our markets were studied. The average value for misture was 11.6%, protein 21.5%, lipids 1.3%, polysaccharides 45.2%, soluble sugars 4.7% and ash 3.9%. Free amino ácido evere identified and yielded from 610 to 1442 mg/100 g. The mean values for the mineral macronutrients were (in %): phosphate 0.17, potassium 1.88, calcium 0.23, magnesium 0.24 and sulphur 2.23. The average contents of micronutrients were (in ppm): boron 24.3, zinc 47.9, copper 174, molibdenium 0.11, iron 330.8 and manganese 17.6. It was found a great variation in the boron (14.2 - 73.8), molibdenium (002 - 0,32) and iron (167.9 - 598.6 ppm) contents. All other components showed a small variation. It was concluded that common beans can be considered a good source of carbohydrates and minerals (macro and micronutrients), and a fairly good source of protein.

Species of the genus Aspergillus, mainly A. flavus strains, occuring in the Araraquarense region (State of São Paulo, Brazil), were isolated and their ability to produce aflatoxin was studied. The isolation was conducted following routine methods in microbiology. The cultures were obtained from samples of peanuts collected in the 'rainy season" and in the "dry season". After the isolation the cultures were classified as follows: 102 A. flavus; 4 A. oryzae var. effusus; 2 A. oryzae; 2 A. parasiticus and 1 A. ochraceus. During the work, 4 cultures were lost, remaining 107 cultures. The cultures were then tested in their ability to produce aflatoxin, which was extracted from the mycelium and from the culture medium. The metabolites were separated by thin layer chromatography using the solvent benzene-ethyl acetate-ethanol and quantified under long wave U. V. light. From 107 cultures of Aspergillus only 33 (31%) produced aflatoxin; seven of those produced it only in the culture medium, while two, only in the mycelium. The production of aflatoxin was much higher in the mycelium than in the culture medium; some of them produced very high quantities, up to 400 p.p.m. of B1 and 300 p.p.m. of G1. From the 33 cultures producing aflatoxin, 32 belonged to the A. flavus species and only one to the A. oryzae. Previous studies when high yields of aflatoxin G1 as related to B1 were reported in that region, were confirmed in the present work.

Two investigations were conducted to find ways to control enzymic browning in the elaboration of banana figs. Bananas were treated with SO2 by immersion in a solution of potassium metabisulfite of which were studied concentration, temperature, pH and time of immersion as well as the resting time of the fruits, after the treatments. The results showed that the best treatment was to dip the fruits for 10 minutes in the 2% solution at 40°C, and pH 2,9. Resting before drying did not improve the products. The shelf life of the products, with the best treatment reached 3 months, with commonly used celophane wraping. Preliminary tests, pre-heating before immersing the fruits showed the possibility of improving the penetration of SO2 and so the enzymic browning control.

The present work was conducted to check the influence and interaction of pre-heating (in oven) and removal of the external skin of bananas in the elaboration of banana figs. These treatments were employed before dipping the fruits for 10 minutes in a 2% solution of potassium metabisulfite heated to 40°C with the pH of the solution adjusted from 3.4 to 2.9. It was concluded that pre-heating the fruits influenced positively the control of enzymic browning. The removal of banana external skin did not influenced the samples pre-heated but did it negatively in the samples not pre-heated.

The present work was conducted to find ways to control enzymic browning by poliphenoloxidase in the elaboration of banana figs. Bananas were treated with SO2 by immersion in a solution of potassium metabisulfite of which, concentration, temperature, pH and time of immersion were studied, as well as the interaction between these treatments and the removal of the fruit external skin. It was concluded that the best treatment was to immerse for 10 minutes in the 2% solution at 40°C, independently of pH control. The interaction of pH and removing or not the external skin of the bananas had no influence on the ensymic browning.

Fertilizers treatments, either by foliar spraying or by soil applications were compared in the cotton crop using the IAC-12 variety with the aim of studying the effects of fertilizers on some physical characteristics of the fibre and the seed. The experiment was carried out on a latossol called «Terra Roxa Estruturada", at the Escola Superior de Agricultura "Luiz de Queiroz of the University of São Paulo, in the State of São Paulo, Brazil. Urea (46% Í), concentrated superphosphate (45% P2O5), potassium chloride (60% K2O) have been used as nitrogen, phosphorus and potassium sources, respectively. The results showed a positive effect on the fiber lenght, fiber strength, the skein strength of cotton yarns and higher seed weight (seed index), when potassium chloride has been sprayed on the leaves. In respect to the uniformitty of the fibre, and fiber fineness (fineness index), there was no influence of the foliar fertilization with none of the three macronutrients; best results have been obtained with the soil application of fertilizers. It must be pointed ou that with the higher rate of phosphorus (60 kg P2O5/ha) the fineness index value was igher. The rate of nitrogen (40 kg/ha) influenced the fiber-strength index, as determined by from Pressley index.

O atual conhecimento relativo à distribuição em percentagem das várias frações de enxofre nos solos provem principalmente dos estudos dos solos de regiões temperadas. Em vista disso, este estudo foi conduzido para determinar as frações do S e as relações C-N-P-S em alguns solos da região subtropical dos Estados de São Paulo e do Paraná, Brasil, e comparar estes valores nestes solos com aqueles nos solos do Estado de Iowa, dos Estados Unidos da América do Norte. As análises das frações de enxofre nos solos dos dois países, indicaram que os solos do Brasil contem sulfato inorgânico adsorvido. Expressos como percentagem do S total, os solos do Brasil acusaram de 5 a 23% (média 11%) de S-sulfato inorgânico, de 20 a 65% (média 40%) de S-ester sulfato, de 5 a 12% (média 7%) de S-ligado ao Carbono e de 24 a 59% (média 42%) de S orgânico não identificado. As percentagens correspondentes nos solos de Iowa foram de 2 a 8% (média 5%) de S-sulfato inorgânico, de 43 a 60% (média 50%) de S-ester sufato, de 7 a 18% (média 11%) de enxofre ligado ao carbono e de 30 a 39% (média 34%) de S orgânico, não identificado. Outrossim, não foi encontrado o enxofre inorgânico não-sulfato em nenhum dos solos analisados. Houve grandes variações nas relações C, N, Ρ e S entre solos brasileiros quando comparados com aqueles do Iowa.

The present work tried to determine the effects of three sites of application of nitrogenous fertilizers as well as the effects of two differents sources of nitrogen on the flowers, conns and cormels productions o Gladiolus grandiflorus L., cv. 'Perusi' cultivated in podzolic soil. All the necessary cultural treatments were given to the plants. Nitrogen applied at planting time has no effect on the plant growth. Its localization in furrows near the root system helps in increasing corn and cormels production. The ammoniacal form permits a better use of nitrogen, influencing the production of floral stems, number of floral buds per stem, higher number and weight of corais. The sodium nitrate causes a despersion in the harvest of the floral stems, while the ammonium sulphate tends to concentrate it.

The presente experiments had as it objectives the cultivation of Gladiolus grandiflorus, L., cv. 'Friendship', in field conditions, studying the effects of parcelling of nitrogenous and potassic fertilization, in relation to corms, cormels and floral spikes production. Theree were effects of parcelling fertilization on number and weight of corms, cormels and floral spikes. In general nitrogen influences more on number of corms and cormels while potassium influences on its weight.

Três doses de N, P e K foram testadas em culturas de gladíolos (Gladiolus grandiflorus cv. 'Perusi') provenientes de três tamanhos diferentes de bulbos (Nº 3, Nº 1 e Jumbo). Todos os tratos culturais necessários foram dispensados aos experimentos cuja instalação se deu em um solo podzolizado da Cooperativa Agrícola de Holambra, em Jaguariúna - SP. Estudaram-se os efeitos de adubação sobre produção de flores, produção de bulbos e de bulbilhos. A resposta do gladíolo aos níveis de fertilização variou bastante com o tamanho de bulbo plantado. São discutidos os efeitos de cada nutriente sobre as características estudadas.

We summed up the results of the studies of 4 cultivars belonging to specie Cucurbita maxima Duchesne and 2 cultivars belonging to specie Cucurbita pepo linneu, taking into account their botanical description because they have not been taxonomically characterized yet, though largely known and grown for their economical value. The breeding works of the cultivars of the above mentioned specie have been carried out since 1943 by the Section of Olericulture of the Agronomic Institute of Campinas (I. A. C.) in view of the economic importance they have. We used seeds from controlled pollination, given away to us by the IAC-Olericulture Section, in order to obtain the plants of the 6 cultivars. The statistical planning followed the steps of distribution at rondom using the 6 cultivars with 10 replications. The botanical description of the cultivars was based upon the morphological characteristics of the vegetative and floral organs and upon the characteristics of the fruits and seeds as well, taking into consideration: a - The shape, dimensions, presence of lengthwise striae and indumentum of the main stem. b - The dimensions and indumentum of the petiole, the angle formed by the outer ribs at the base of the leaf blade and the angle magnitude, the lenght of the ribs, the presence or absence of silvery spots on the leaf blade; width and length of leaf blade. c - The shapes of the tendrils. d - For the male and fgemale flowers: the length of the peduncle, the length of the tube and of the lobules of the calyx and its shape, the length of the tube and of the lobules of the corolla, the diameter of the upper part of the corolla tube, diameter between the apexes of the corolla lobules, the length of the filament and the length of the anther, and the shape of te latter for male flowers; the dimensions, positionings, shape and indumentum of the ovary, length and color of stigma, length of the stigma lobules, the variable shape of the nectariferous disk at the style base for female flowers. e - The dimensions, shape, color, parts, consistence and thichness of the fruit pulp. f - Te dimensions, shape and color of the seed and of the hilum as well. The statistical analysis was made for some characteristics of taxonomical value such as: Leaves: Length of the petiole; magnitude of the foliar angle at the base of the leaf blade, width and length of the leaf blade. Male flower: the length of the peduncle, the length of the tube and corolla lobules, the diameter of the upper part of the corolla tube. Female flower: the length of the peduncle, the length of the ovary, the length of tube and the length of the corolla lobules, the diameter of the upper part of the corolla tube.

This paper describes the fruit and seed morphology of Euterpe edulis, Mart.. The mesocarp has fibrous blade, with 0,5 x 23 mm in average, made of wood fibers, sclereids and spiralated vessels. Endocarp membranous, 0,3 mm thick, with predominancy of sclereids over fibers, lateral hilum, excavated. Opercular area, and operculum with 1,8 mm of diameter. The basal embryo, with cylindrical-conic shape has 3,5 mm length and 1,8 mm in diameter. It has two regions, one conic and the other cylindrical. They correspond respectively to the median part and to the sheath of the cotyledon. The firts one develops during the germination in haustorium, and the second enclosed the plumule and the hypocotyl-root axis. The radicle is enclosed by the coleorhiza and the plumule by an coleoptile.

No summary/description provided

In the present work, the occurrence of aflatoxins B and G, as well as a possible correlation between both were studied in 56 samples of peanut flower from 9 oil mills of the region Araraquarense, in the State of São Paulo. The samples were obtained in four collections representing material from two crops in two different seasons: March and May in the rainy season and July and September in the dry season. From the results it was concluded that: a) the occurrence of aflatoxin was generalized in that region, for all the samples were toxic; b) the toxicity level was found to be very high (figures from 0.1 to 20.0 ppm) being higher in the rainy season - average of 4.55 ppm, against 2.40 ppm in the dry season; c) it was considered that only 16.07% of the material examined could be utilized for admixturing in feedstuffs; d) it was observed a high yield of aflatoxins G, being higher than B in six samples; e) it was found a positive correlation, statistically significant, in the production of the aflatoxins B and G.

O presente trabalho teve como objetivo estudar as interações lineares, N' xP';N' x K'e P' x K', em quatro grupos de ensaios fatoriais 3³ de adubação de milho, com N, P e K, num total de 117 experimentos com 3.159 parcelas. Os grupos eram assim constituídos: Grupo 1: 53 ensaios, realizados em Ribeirão Preto (SP), utilizando-se as doses 0; 40 e 80 kg/ha de N, de P(2)0(5) e de K(2)0. Grupo 2: 41 ensaios, realizados no Estado do Rio de Janeiro, com as doses: 0, 30 e 60 kg/ha de N e de K(2)0 e 0; 60 e 120 kg/ha de P2Os. Grupo 3: 10 ensaios, realizados no Triângulo Mineiro, com as doses: 0; 75 e 150 kg/ha para os três nutrientes. Grupo 4: 13 ensaios, realizados: 7 no Triângulo Mineiro e 6 em Patos de Minas (MG), utilizando-se em ambos os subgrupos, as doses: 0; 60 e 120 kg/ha para os três nutrientes. Foi observado que somente as interações N' x P', referente às doses 0 e 1 no grupo 1, e P' x K', referente às doses 0 e 2 no grupo 2, foram significativas. É possível, pois, concluir com grande generalidade, que nos ensaios fatoriais 3³ de adubação de milho, quando se consideram doses moderadas de nutrientes, as interações são de importância secundária e, na grande maioria dos casos, são de pequena monta, quando comparadas aos efeitos principais dos nutrientes.