RCAAP Repository

This paper relates the solubilities in 2% formic acid solution of various phosphate rocks used in Brazil, in function of the particle size and the relation of sample weight with extractor volume. The results were compared with 2% citric acid solution and wake possible the following conclusions: a) the classification in decreasing order of solubility for two extractors was bone degelatined flour, hyperphosphate (Africa phosphate), Florida phosphate, Olinda phosphate, Araxá phosphate and Alvorada phosphate; b) the Africa phosphate solubility is much higher in formic acid solution than in citric acid solution; c) the Florida and Araxá phosphates solubilities were similar for two extractors; d) the Olinda and Alvorada phosphates were slightly higher in citric acid solution than formic acid solution; e) the formic acid solution was more effective in the solubilization of bone degelatined flour than citric acid solution.

Callus was established from leaves and shoots of Coffea arabica L. on nutrient medium with various levels of auxins and kinetin. Morphogenesis is controllable in such callus tissues by manipulation of the growth factor levels in the media. The study shows that callus culture obtained from leaves are in different states of differentiation, i.e., although the calluses were similar in appearence, their morphogenetical potential was different. The cells in culture show a great range of growth and form, and that form and behaviour of such cells do not correspond with recognized cell types in normal plant tissues or meristems. Proembryoids and vascularization (Fig. 1), giant cells (Fig. 4) and other patterns of cell differentiation (Figs. 2 and 3) were observed. The initiation of an organized system is probably dependent upon some rather specific environmental conditions. The extent to which certain specific types of differentiation are concomitant would seem to be a reflection of the extent to which common factors are involved. Thus, in this type of change, casuality of the nuclear change to the other changes would be unlikely.

Diurnal transpiration rates of four citrus rootstocks were measured during 12 hours separated by intervals of 60 minutes, through the weighing method. Plants of Poncirus trifoliata, Citrus aurantium, Citrus sinensis, and Citrus limonia do not present statistical differences in the daily march of transpiration. In the studied conditions C. limonia showed higher leaf area than P. trifoliata, C. aurantium, and C. sinensis. There was a positive correlation between leaf area and transpiration of the four citrus rootstodks.

O presente trabalho tem por objetivo a aplicação do método colorimétrico de determinação do silício na análise da silica total e solúvel em solos. Para a realização de tais objetivos foram focalizados, entre outros, dois aspectos principais: o estudo sobre os interferentes e a solubilização da silica, mediante ataque de amostra, a quente, com um ácido mineral e ácido fluorídrico, seguido da adição de ácido bórico. Uma vez estabelecidas as condições adequadas à solubilização, os procedimentos estudados tiveram sua precisão e exatidão avaliadas através de sua aplicação em amostras de areia cuidadosamente lavada. À seguir, procedeu-se à aplicação das técnicas preconizadas na análise de solos, associando-se ao método colorimétrico de determinação do silício, e, com a finalidade de comparação, as amostras foram analisadas também pelo método gravimétrico. Os dados obtidos permitem considerar as técnicas colorimétricas, bem como aquelas de solubilização da silica, satisfatoriamente exatas. Os teores de silica solúvel foram determinados a partir de extração por soluções aquosas de CaCI2 0,0025M, H3C-COONa 0,01 M, H2SO4 0,025M, e por água destilada, com o emprego do método do azul de molibdênio.

In the spectrophotometric determination of cobalt with 2,2'-dipyridyl ketoxime, the effects of several ions were studied. Among tre ions studied, only cupric nichelous, ferric and manganous cations interfered. The interference caused by cupric, nichelous and ferric cations was iliminated by a second extraction of the colored compound with a 2N hydrochloric acid solution. The interference, of the manganous cation, disappear when cobalt is determined in the presence of other ions.

As a conclusion of the studies on the spectrophotometric method using 2,2,-dipyridyl ketoxime, it is suggested a technique for the cobalt determination in plants. The method, as it is proposed, presents both precision and accuracy sonsidered satisfactory, and the least relative error of the concentration is obtained in the range from 0,9 to 9,0 or 1,0 to 10,0 microgrames of cobalt in 3ml of solvent. It follows Beer's law and the molar absorptivity of the compound is 17.685. The results of cobalt determination in several vegetables are presented.

The effects of growth regulators on strawberry cultivar "Monte Alegre" were studied in Piracicaba, State of Sao Paulo. Succinic acid -2,2 - dimethylhydrazide (SADH) 5000 ppm, (2- chloroethyl) trimethylammonium chloride (CCC) 2000 ppm, and gibberellic acid (GA) 550 ppm were sprayed, and also three applications of indoleacetic acid (IAA) 10 ppm or GA 10 ppm were made. It was verified that although GA 550 ppm, SADH and CCC decreased yield, three applications of IAA 10 ppm or GA 10 ppm have promoted a tendency to increase strawberry yield. It was noted that growth regulators do not alter number of fruit, and GA 550 ppm promotes reduction in fruit mean weight. GA ppm increased number of fruit on 3rd and 4th weeks of harvesting, decreasing progressively in subsequent weeks. It was observed that GA 10 ppm or IAA 10 ppm promotes an increase in peduncle length, casing harvesting.

Green bean coffee (Coffea arábica L., cv. Mundo Novo) was treated with petroleum and oil was analised in relation to fatty acid composition. Three methods of esterification were used and the results statistically analised. Significant differences were not observed between methods of LUDDY et alii (1960) and A.O.A.C. (1965). The method with previous saponification showed significant difference only to linoleic acid when was compared with A.O.A.C. method.

Avocado (Persea americana cv. Pollock) samples were used to compared two methods of oil extraction: the samples were dried at 70°C and treated with petroleum ether. Fresh samples were treated with chloroform-methanol (2:1, v/v). Significant differences were not observed between these two methods in relation to oil conten, non-saponifiable fraction, total fatty acids and fatty acid composition of oil avocado. Oil content of the sample varied from 5.88 to 7.02% on a fresh weight basis while non-saponifiable fraction from 2.17 to 4.34% on oil weight basis. Palmitic, stearic, palmitoleic, oleic and linoleic acids were detected and quantified.

Several species of Brazilian fresh-water fishes: pintado (Pseudoplatysma corruscans), mandi (Pimelodus darias), lambari (Astianax bimacidatus), peixe-cachorro (Acestrorhynchus falcatiis), saguiru (Curimata elegans), piava (Leporinus sp.) and piranha, were analised in relation to lipid content, cholesterol, free fatty acids and ruonj-saponifiable fraction. Singinificant differences were observed between species in these several analysis. Higher oil e cholesterol contents were observed in mandi. Cholesterol was probably the principal constituent of non-saponifiable fraction of the fishes studied.

An analytic key was done based upon morphological characteristics of fruits and seeds of 13 cultivars belonging to 3 species to identify them. It was used seeds from controlled pollination. Is was considered: fruit-shape, epicarp color, peduncle dilatation and consistence, seed-hilum and longitudinal lineal salience.

Trials were established on four soil types (Latosolic B Terra Roxa - LR; Ortho Dark Red Latosol - LE and Red Yellow Podzolic Laras variation - PVls in the state of São Paulo and Textural B Terra Roxa - TE in Parana to study varietal and soil effects on macronutrient composition of sugarcane leaves and to do a nutritional survey of varieties by foliar analysis. A randomized block designwas used with four replications of 16 varieties (CB 41-76; CB 45-155; CB 47-355; CB 49-260; CB 56-171; CB 61-80; IAC 50/134; IAC 51/205; IAC 52/150; IAC 52/326; Co 740; Co 775; CP 51-22 and NA 56-62). Varieties were planted under the same conditions of climate, fertilization, tillage and age, sanitation and source. A central 20 cm portion of each +3 leaf was taken (except for midrib for determining amounts of N, R, K, Ca, Mg and S, expressed -on a dry weight basis. Leaf samplesof 20 leaves per plot were selected at four months of age, for analysis. From the results obtained it was conclued that: a) There is a varietal effect on leaf composition of major elements, independent of soil type; b) Soil type has an influence on leaf composition of different varieties; c) The higher nutrient levels in the leaves did not always result in the highest production intpol/ha; d) Because of soil and varietal influence on leaf composition it is rifficult to generalize critical nutrient, levels obtained from foliar diagnosis; e) Critical levels of nutrients obtained from foliar diagnosis for une variety do not represented the same levels for all varieties.

This research deals with the effect of (NH4)2 SO4 (ammonium sulphate) and exogenous growth regulators on weight average of fruit of tomato cultivars "Angela" and "Roma". In two experiments, (NH4)2 SO4 (2g/l soil), succinic acid -2,2_ dimethylhydrazide (SADH) 3000 ppm, SADH plus (NH4)2 SO4, (2-chloroethyl) trimethylammonium chloride (CCC) 2000 ppm, CCC plus (NH4)2 SO4, gibberellic acid (GA) 100 ppm, GA plus (NH4)2 SO4, and check treatment, were applied. In two other experiments, 1-(2,4-dichloraphen-oxyaedthyl) -3,5-dimethyl pyrazole at concentrations of 3,75, 15,00 and 7,5 ppm, and (2-chloroethyl) phosphonic acid (CEPA) 500, 1000 and 1500 ppm, were used. It was observed that SADH promotes reduction in the weight average of fruit of tomato "Angela" in relation to treatment with (NH4)2 SO4. Ammonium sulphate in the soil reduced the detrimental effects of foliar application of SADH. Tomato plants "Angela" and "Roma" sprayed with CCC, GA, Tomakon and CEPA did not show variation in the weight average of fruit.

O presente trabalho teve por finalidade descrever comparativamente as características morfológicas dos frutos e das sementes de 13 cultivares de Cucurbita. Para identificar e classificar botanicamente as espécies das cultivares em estudo, servimo-nos da chave descrita por Bailey, que considera entre outras, as características dos pedúnculos dos frutos e as características das sementes. Desta maneira separamos as cultivares em três espécies: Cucurbita moschata Duchesne com as seguintes cultivares: 'Menina-verde', Taça', 'Tatui', Menina-amarela', 'Canhão', 'Redonda-de-amparo' e 'Menina-creme'. Da espécie Cucurbita maxima Duchesne estudamos os frutos e as sementes das cultivares 'Exposição', 'Coroa', Όn-de-ganso' e 'Mogango-verde' e para Cucurbita pepo Linneu as cultivates 'Small-sugar' e 'Cas-erta'. Realizamos o referido trabalho no Campo Experimental do Departamento de Agricultura-Horticultura da ESALQ, em Piracicaba, e as cultivares estudadas são as mais recomendadas pela Secção de Olericultura do Instituto Agronômico de Campinas. Foram semeadas de cada cultivar 3 a 5 sementes por cova e repetidas por 10 vezes. De cada planta adulta colhemos 3 frutos e nos frutos anotamos as seguintes características morfológicas: coloração do epicarpo, forma, resistência da casca, dimensões e peso; semente: dimensões, número de sementes normais e anormais, peso das sementes.

Eight species of ripe fruits, mango (Mangifera indica), banana (Musa cavendish), lemon (Citrus aurantif olia), "romã" (Punica granatum), orange (Citrus sinensis), pineapple (Ananas comosus), "jaboticaba" (Myrciaria cantiflora) and "cabeludinha" (Eugenia tomentosa) were analised in relation to total soluble carbohydrates, glucose, sucrose and fructose contents. In general, total soluble carbohydrates of these fruits showed 80% in form of sucrose, glucose and fructose. Sucrose was the principal sugar component in mango, jabuticaba, pineapple, orange and banana. In comparison with others fruits, banana had presented the highest total soluble carbohydrates content (20.44% on a fresh weight basis).

It was observed that gibberellic acid 100 ppm promotes high incidence of blossom-end rot when a high level of ammonium sulphate was used. Under the same conditions, treatments with succinic acid -2,2-dimcthylhydrazide 4,000 ppm, (2-chloroethyl) trimethylammonium chloride 2,000 ppm and indole-3-acetic acid 100 ppm, caused, low incidence of blossom-end rot. It was proposed a mechanism of blossom-end rot incidence in tomatoes.

This research deals with the effects of exogenous growth regulators on development of the tomato cultivar «Miguel Pereira». Observations of tomato plants treated with (2-chloroethyl) trimethylammonium chloride (2,000 ppm) and succinic acid -2,2-d:methyi-hydrazide (3,000 ppm) showed that growth regulators induced little variation in plant height. Gibberellic acid (100 ppm) caused greater variation in height.

To study the influence on fruiting, (2-chloroethyl) trimethylammonium chloride (CCC) at concentration of 2,000 ppm, succinic acid-2,2-dimethylhydrazide (SADH) (3,000 ppm), gibberellic acid (GA) (200 ppm), and (2-chloroethyl) phosphonic acid (CEPA) (200 ppm) were applied. Treatments with CCC, CEPA, GA and SADH did not affect the total weight of tomato fruits. The growth regulators did not promote changes in fruit number. Applications of CCC and CEPA did not affect the fruit weight average; however, spraying with SADH and GA reduced the fruit weight average.

Analysis have been realized to evalue the content of macronutrients (N, R, K, Ca and Mg), and of micronutrients (Cn, Fe, Zn and Mn) in the leafs of five forest species: Araribá rosa (Centrolobium robustum), Guarantã (Esenbeckia leiocarpa), Ipê roxo (Tabebuia heptaphylla), Genipapo (Genipa americana) e Joazeiro (Zizyphus joazeiro). The statistical analysis and interpretation of the data allowed the following conclusions : a) Concentrations of macro and micronutrients varied among the species. b) Concentrations of macro and micronutrients varied according to position of the leaf on the branch and also to the species.

Leaves of several tree species (Astronium urindeuva, Aspidosperma ramiflorum Muell, Tabebuia flavescens Grise, Terminalia catappa and Joannesia princeps Veill) have been analysed for N, R, K, Ca, Mg, Fe, Zn, Cu and Mn. Results indicated that the mean concentration of these elements are within the average; range of nutrients concentration determined, by several authors. Nutrients content have no regular variation among leaves of different ages, except for Terminalia catappa. Astronium urundeuva is considered a calcicolous plant and this caracteristic could be inferred by the nutrient contents of its leaves.