RCAAP Repository

In order to control the citrus rust mite, adult orange-trees were submmited to the following treatments: A) check; B) pyrethroid S-604, 102g; C) S-604, 153g; D) S-604, 204g; E) juvenoid S-599, 22g; F) S-599, 44g; G) bromopropilate, 530g (standard treatment). Each tree was sprayed with 7.0 liters of liquid (water plus pesticide). Four evaluations were made: two days before spraying and 05, 19 and 40 days after the spraying. All treatments were efficient up to forty days after spraying. In the last evaluation the mite population had decreased to almost none.

This study was carried out with the objctive of obtaining information about the relationship between land forms and soils developed from cenozoic materials that occur in the São Francisco river valley and tributaries. The region is located in its Jequitaí, Minas Gerais state, and has a subhumid climate. Soil moisture and temperature regimes are ustic and isothermic, respectivelly. A soil toposequence represented by five pedons was chosen. In the oldest surface from a Terciary material a Typic Haplustox was developed. The other pedons are developed from Holocenic materials deposited by the Sao Francisco river. These are very young soils with argillic horizons, represented by Ultisol and Molisol. Profile 1, a Typic Haplustox, has only resistent minerals in the sand fraction, and kaolinite is the dominant clay mineral. The Plinthic Haplustox (Profile 2) located in a more recent surface has some calcium plagioclases and mica in the sand fraction. Wheathering minerals increase with depth. The other soils, more recent and developed in the youngest surface, are an Oxic Plintaquult (Profile 3), Fluventic Plintustult (Profile 4) and Fluventic Argiustol (profile 5). In these soils the amount of feldspat and micas increase from Pedon 2 to Pedon 5. These minerals are associated with a recent depositional process due to Sao Francisco river work.

A field experiment was conducted with the banana plant Prata cultivar, in a Cambisol, in Cariacica, Espírito Santo State, Brazil, to study the major nutrient uptake, removal and return to the soil. Three mother (up to harvest), and ratoon plants (up to months after emergence) were selected at twelve and nine different development stages , respectively. Samples of leaf, petiole, pseudostem, rhyzome, stalk, bud flower and fruit were taken. Percentages of N, P, K, Ca and Mg, were measured. The following conclusions, for mother and ratoon plants, were drawn: a large amount of major nutrients are needed for vegetative development and yield; major nutrient uptake are influenced by dry matter production, except K in the petiole; the uptake ratio between the major nutrients is 20 K : 12N : 10Mg: :9 Ca : 1 P for the mother plant and of 26 .5K:8N :4.5Mg: : 4.5Ca:l P for the ratoon plant. A high amount of major nutrients can be returned to the soil with plant management. In a rational program of major nutrient fertilizer, it is necessary to take into account the amount of nutrients exported by harvest, especially N, P and K. The ratoon plant accumulated a larger amount of major nutrients than the mother plant.

Levels of trans-aconitic, malic, malonic and succinic acids were measured in sugarcane juice from three varieties in four maturity stages. Trans-aconitic acid represented about 84% of the total organic acids analysed in sugarcane juice followed by malic acid with 14%. Oxalic, glutaric, alpha-ketoglutaric and citric acids were found in levels lower than 1% of total organic acids. The content of trans-aconitic, malic and succinic acids decreased with the stage of maturity while malonic acid increased. No significant differences were observed among the varieties studied in relation to trans-aconitic acid content.

Young Sesbania plants were grown in nutrient solutions for the purpose of studying deficiency symptoms of the following elements: N, P, K, Ca, Mg, S, and B. The present paper describes the symptons on Sesbania plants that were associated with nutrient solutions defficient in the various elements listed. The paper presents also the satisfactory range and defficient range in the leaves: N% 3.12 - 1.70; P% 0.25 - 0,03; K% 2.10 - 0.15; Ca% 1.32 - 0.56; Mg% 0.47 - 0.09; B ppm 77 - 23. The sulphur concentration in normal plants was 0.16%.

A study was made of the effect of different levels of N P K: N = 0,200, 400; P = 0,400, 800 and K = 0,200, 400 kg/ha, under field conditions, on the seedling production of ginger-lily, Hedyohium gardnerianum Sheppard ex Ker-gawl, Zingiberaceae and the influence on the dry matter Weight. From the data it was concluded that the best results were reached with the following levels: 20g of N; 80g of P; 20g of K/m² 40g of N; 80g of P; 40g of K/m² 20g of N; 40g of P; 40g of K/m².

The authors observed that leaf potassium concentration correlates negatively with soil silt content. Leaf copper concentration presents a negative correlation with sand and a positive correlation with clay.

Four-year old uvalha trees were pruned in August, 1984. Three treatments were performed: a) control-no pruning, b) pruning of twigs up to 5mm thick and c) pruning of twigs up to 10mm thick. Average production per tree, for that same year, was the following for each treatment: 4.118 kg (control); 0.860 kg (light pruning); 0.230 kg (severe pruning). In that way, the types of pruning performed showed to be a bad practice to the production of uvalha trees. These results indicate that pruning as performed is not recommended.

The application of micronutrients in the soil, in a homogeneous way, with the least contact with soil particles may increase its agronomic efficiency. Storing a solution of fertilizers in a solid porous medium, which is used as a vehicle for application, links great homogeneity to low soil contact. The Solid Capillary Support for Fluid Fertilizers (SC) was used as porous solid medium. It is a compacted cylinder made of gypsum (CaSO4 • 2H2O), developed experimentally by ULTRAFERTIL. The SC was an efficient way in supplying micronutrients, resulting in similar or better yields in relation to direct application in the soil.

Transcarbamilase de ornitina (E.C. 2.1.3.3) extraída de folhas de feijoeiro (Phaseolus vulgaris L. cv. carioca) com 31 dias de maturidade foi parcialmente purificada com sulfato de amônio em pH 7,2 e 7,8. A enzima apresentou as seguintes propriedades: pH ótimo 7,8, temperatura ótima 40°C, Constante de Michaelis para ornitina de 3,18mM e para carbamil-fosfato de 3,93mM.

The effect of potassium deficiency on glutamate dehydrogenase(EC. 1.4.1.2) and glutamate synthase (EC. 2.6.1.53) activities in leaves of two cultivars of bean plants (Phaseolus vulgaris L.) was studied. The results showed an increase of glutamate dehydrogenase and a decrease of glutamate synthase activities in potassium deficient plants of the two cultivars studied.

Young rubber trees were cultivated in Bolle-Jones nutrient solutions modified for iron supply. A separate solution of aluminum was prepared by dissolving a thin aluminum foil with HCl 1N. From these stock solution the following solutions were prepared: 0, 5, 10, 15, 20 and 25ppm of aluminum. The plants remained for 24 hours in nutrient solution and for another 24 hours in the aluminum solutions. The procedure was carried out during 95 days. After 95 days the plants were harvested and divided into top whorls, remaining whorls, stem and roots. The material was analysed for N, P and K by routine methods. The authors concluded that the rubber plant is tolerant to concentration up to 15ppm of aluminum in the substract. Higher levels induce malnutrition of N, P and K in plants.

The concentration of macro and micronutrients in roots, stems and leaves of water hyacinth was determined. One kg of the whole plant contains the following quantities of elements: N-10.3g, P-1.6, K-49.0, Ca-25.8, Mg-10.5 and S-3.3; B-25mg, C@-10,436, Co-1.9, Cu-1.2; Fe-8,969, Mn-1,415, Mo-2.3, Ni-4.0 and Zn-41.6. After comparing the composition of water hyacinth with that of stable manure, its use as green manure is discussed.

Procurou-se avaliar o comportamento agronômico do Suporte Solido Capilar para Fertilizantes Fluídos (SC), que é um produto fertilizante experimental desenvolvido pela ULTRAFÉRTIL com comportamento potencial de Fertilizante de Solubilização Lenta. Procurou-se avaliar seu efeito sobre as plantas e sobre os solos além de compará-lo com fertilizantes convencionais, através de um ensaio de efeito residual. O SC não se comportou como Fertilizante de Solubilizaçao Lenta, igualando-se aos outros tratamentos. O K quando aplicado via SC é melhor aproveitado pelas plantas e a presença do SC no solo provoca variações nos teores de P, Ca e S - SO4-2 no solo.

In order to establish the critical level of phosphorus in annual varieties IAC-20, IAC-19, IAC-17, CNPA 78/SME-4 and in perennial varieties CNPA 2M and CNPA 3M young cotton plants were grown in nutrient solutions containing the following phosphorus concentrations: 0.38ppm, 1.14ppm, 3.42ppm, 10.26ppm and 30.78ppm. The solutions were replaced every seven days. From plants at the age of 44 days, 59 days and 74 days, the 5th leaf from the apex of the plants were collected and separated into petioles and leave blades and the phosphorus content was determined. The authors concluded: - The petioles or leave blades are adequate for the determination of the critical level of phosphorus.

Effect of milk treatment on yoghurt quality was investigated by heating the milk in water bath at 65°C for 30 min., 75°C for 10, 20 and 30 min. and 85°C for 10, 20 and 30 min. Yoghurt quality was evaluated by a ten trained panelists using a hedonic scale from 0 to 6. The panelists were asked to judge flavor and consistence of the product. The statistical analysis of the results showed a significant preference for the product made from milk heat-treated at 85°C for 30 minutes, although the products made from milk heated at 75°C for 10, 20 and 30 minutes had pH and titratable acidity as desired.

A study was made of the effect of strawberry pulp and coconut milk on the flavor of soybean milk yoghurt to which cow milk was added (85% and 15%, respectively). The results indicate that coconut and strawberry significantly contributed to improve the flavor of the product which, even without this addition, is of acceptable flavor.

A pot experiment was conducted in a green house in Piracicaba, Brazil, in order to determine the visual symptoms of deficiency, and the effects of micronutrient omission in P. caribaea var. hondurensis, P. caribaea var. bahamensis and P. caribaea var. caribaea seedling height and dry matter production. The following treatments were employed: complete, without boron, without copper, without iron, without manganese and without zinc. Washed sand was used as a substrate. The plants were watered twice a day with the corresponding nutrient solution. After the deficiency symptoms were established, the plants were cut and separated into needles, branches and roots, washed, dried at 75°C and weighed. Visual symptoms were described. Pinus caribaea var. hondurensis and P.caribaea var. caribaea were more affected than P. caribaea var. bahamensis seedlings by boron omission. P. caribaea var. bahamensis and P. caribaea var. caribaea were more affected than P. caribaea var. hondurensis seedlings by copper omission. Pinus caribaea var. hondurensis was the most affected by iron omission.

This experiment was conducted in order to evaluate the effect of planting dates on the behavior of ten legumes used as green manure. Field plots were laid out in a completely randomized split-plot design combining 10 legumes and four planting dates to total 40 treatments. Results obtained indicated that total dry matter production was influenced by sowing dates for all the legumes studied. Black mucuna (Styzolobium atterrimum) stood out in the January sowing and pigeon pea (Cajanus cajan) stood out in the October sowing. Black mucuna is indicated as the best option for rotation with a short cycle summer crop.

Chemical control of the tropical mite was evaluated by means of a field test conducted in Tiete, State of São Paulo, Brazil. Seven treatments with four replicates each were applied to plots of 150m². Treatments and their respective active ingredients were as follows: A) check; B) triazophos, 300g; C) triazophos, 150g + pheromones (multimethyl alkenols), 4.77g; D) propargite, 1080g; E) abamectin, 6g + pheromones (multimethyl alkenols), 6.67g; F) profenophos, 400g; G) sulfur, 3000g. Best results were obtained with treatment B (triazophos), followed by G (sulfur) and the two mixtures with pheromones (C and E) (triazophos plus multimethyl alkenols and abamectin plus multimethyl alkenols) (tables 2, 3 and 4). Predador mites were considered.