RCAAP Repository

Changes in soil water regime during vegetative growth and yield production of potato crop was not equally affected by soil water depletion. Concerning to yield production the results show that the soil water depletion effect are closely related to intensity and duration of water deficits and stage of plant growth in which they occurs. So, it was stablished that during the stage of tuberization and tuber development, the plant exhibited higher sensibility to water deficiency than in the initial or final stage of plant growth. On the other hand, moderate deficits (-1.0 bar of soil water matric potential) occurring in the initial stage of plant growth did not have any effect in tuber yield. This was attributed to the resumption of growth in the following stage. However, when a more severe water deficiency occurred (-5.0 bars of soil water matric potential), it was not observed the resumption phenomenon. In this case, an irreversible decrease in growth had the effect of decreasing yield. Soil moisture depletion in the final growth stage, about 60 days after plant emergence, did not decrease tuber yield, which increased plant water efficiency. When water supply was suppressed in this stage, the senescence was hastened in 16 days when compared to the other treatments with higher levels of soil moisture. As was evidenced, the vegetative growth is not an absolute index of the potato yield production.

Water requirement for onion (Baia Periforme Precoce Variety) was studied by means of field experiments in which water was supplied by the furrow-irrigation method. The "class A" pan was used to evaluate the water need or this crop. Four treatments were used in which soil water potential was maintained at a minimum of -0.5; -1.0; -6.0 and -15.0 bars. Soil moisture content was controlled gravimetrically. The results obtained led to the following main conclusions: a) yield of onion bulbs increased with soil water potential; b) the following ratios (ER/E0) were determined for the best treatment in which the minimum soil moisture potential was -0.5 bar: 0.64; 0.63 and 0.63 for the second, third stages and the addition of these, respectively.

An arbitrary thin section of a given mineral is considered as examined on the universal stage. The theoretical possibility of determining the principal refraction indexes by analytical method from data obtained from extinction and birefringence measurements is studied. A mathematical demonstration is presented to show that it is theoretically possible to determine Np, Nm and Ng and, independently, B = Ng - Np.

Seedlings of cotton were treated 15 days after germination, with (2-chloroethyl) trimethylammonium chloride (CCC) at concentrations of 20, 200 and 2,000 ppm and the check to verify the effect of the compound on the growth of the plant. The experiment was done under greenhouse conditions in 1974. The main proposal of this work is to study the variation of plant height, percentual plani variation height, net assimilation rate, relative growth rate and the leaf area ratio with application of CCC. The growth regulator promotes decrease in plant height and in percentual plant variation height, 6 and 12 days after application of CCC. CCC at concentration of 2,000 ppm causes, 12 days after spray, the inferior heights and fewer percentual variation heights in cotton plants. Application of CCC at concentrations of 20, 200 and 2,000 ppm, promotes proportional diminutions in the net assimilation rate, relative growth rate and in the leaf area ratio in relation to check.

Seedlings of cotton were treated 19 days after the sowing with gibberellins at concentrations of 2, 20 and 200 ppm and the check to verify The effect of the compound on the growth of the plant. The experiment was done under greenhouse conditions in 1974. The main proposal of this work is to study the variation of plant height, net assimilation rate, relative growth rate and the leaf area ratio with application of gibberellins. The growth regulator at concentrations of 2, 20 and 200 ppm increased plant height, respectively in 27, 48 and 65% when compared to the control. Application of gibberellins at concentrations of 2 and 20 ppm promotes increase in the net assimilation rate and in the leaf area ratio of cotton. The relative growth rate was superior in the plots that received gibberelins at concentrations of 2, 20 and 200 ppm. It was verified that gibberellins at 200 ppm has a tendency to promote reduction in the net assimilation rate and slight variation in the leaf area ratio in relation to check.

In Brazilian supermarkets, ground beef may sometimes be prepared using meat that has been previously frozen and stored to be consumed during periods of the year when there is a decrease in the amount of fresh meat available. The results of this study suggest that a modified resazurin test, previously described by the authors for the evaluation of ground beef microbiological quality, can be used in different periods of the year, even if frozen meat is involved.

Estuda-se a possibilidade da aplicação prática do método analítico na determinação da grandeza da indicatriz ótica de anidrita, cujo desenvolvimento teórico foi realizado por ABRAHÃO e MARCONI (1975). Os valores de λ e de µ λ, necessários à obtenção de Ng, Nm e Np, foram calculados por diversos processos diferentes e os resultados comparados. Concluiu-se que os valores de λ são muito discrepantes. Quanto a µ λ = (Ng - Np)/2, obtiveram-se resultados praticamente constantes, para todas as vias de cálculo utilizadas. Os autores concluem, finalmente, que as determinações de Ng, Nm e Np são inviáveis na prática, em face da extrema precisão que seria exigida das medidas de birrefringência, necessárias ao desenvolvimento do método e impossíveis de serem alcançadas na atualidade.

Studies were carried out to establish the effects of exogenous growth regulators on Vitis (labrusca x vinifera) 'Niagara Rosada' fruiting. The investigations were done in the Jundiaí Research Station, Agronomic Institute State of São Paulo, always using disease-free vineyards of good productivity. The morphological transformations of clusters were carried out under the following aspects: weight, length and width of cluster; number of berries; weight, length average and width average of berries; length average/width average ratio of berries; number of seeds; length and diameter of secondary rachis. That characteristics were determined at the time of maturity plus the total sugars, total acid, Maturity Index and reducing sugars in samples of all treatments. The experiment were conduced in order to determine the doses that resulted in the most beneficial effects, always using applications by immersion of the inflorescence. The experiment consisted of appplications of (2-chloroethyl) phosphonic acid (CEPA) at concentrations of 50, 100, 250, 500, 1,000 and 2,000 ppm, 14 days before flowering; treatments with gibberellic acid at concentrations of 100 and 200 ppm before full bloom, 10 days after full bloom, and both before plus after full bloom. Treatment with CEPA 100 ppm plus gibberellic acid 100 ppm before full bloom and check treatment were also used. The use of CEPA before flowering at the concentrations used, did not result in good results in 'Niagara Rosada' clusters; applications of gibberellic acid did not differ significantly from the nontreated vines under the conditions studied.

The objective of the present work was to examine the differences in growth, yield, accumulation and transport of nutrients between the cultivars Agroceres 256, Agroceres 504, Centralmex, H-7974 and Piranão. The experiment was carried out in the municipality of Piracicaba, State of São Paulo, Brazil. The soil type was a sandy oxisol of medium fertility, expect for K which was low. The experimental set-up was a randon block design with four replications. Common cultivation practices were followed, and the fertilizer used consisted of 83 g of a formula: 30-120-70, per meter length at planting, and 33 g of the formula: 50-0-45 per meter length as dressing 22 days after germination. The plant population density was 50,000 per hectare. Plants were collected for analysis at 20 days after germination, and there after at intervals of 20 days up to 120 days. The plants were divided into "stems + leaves", tassels, and ears for chemical analysis of N, P, K, Ca, Mg and S. Conclusions: Growth - The cultivars produce maximum quantities of dry matter of 327 to 381 g per plant at the age of 100 to 106 days. - Differences between cultivars in terms of dry matter accumulation in the vegetative parts of the plant is not necessarily relate to the dry weight of the ear. Accumulation of nutrients - There are no differences in the quantity of N, P and K taken-up by the cultivars, although during the period of rapid growth some differences may appear. - Differences in the accumulation of Ca, Mg and S are detected when the quantities of these nutrients approach the maximum. The cultivar H-7974 presented the highest quantities of Ca and Mg where as Agroceres 504 was richest in S. - The maximum level of nutrients are attained in the following period in days: N (89-100); P (101 -120); K (58-66); Ca (75-94); Mg (100-120) and S (93-95). - The maximum quantities taken-up in mg/plant are:N (3,169-3,878);P (541-642); K (3,850-4,693); Ca (582-782); Mg (654-943); S (444-799). Yield - No differences were found between cultivars for grain production. Transport of nutrients - The re were no differences in the amounts of nutrients in the grain between cultivars. - The transport of nutrients into the ears of the different cultivars are the following order (per hectare harvested, 50,000 plants): N (111-143 kg); P (22-30 kg); K (30-45 kg); Ca (0.7-1.1 kg); Mg (10-12 kg) and S (9-13 kg).

The objective of the present work was to examine the differences in growth, yield, accumulation and transport of nutrients between the cultivars Agroceres 256, Agroceres 504, Centralmex, H-7974 and Piranão. The experiment was carried out in the municipality of Piracicaba, State of São Paulo, Brazil. The soil type was a sandy oxisol of medium fertility, except for K which was low. The experimental set-up was a randon block design with four replications. Common cultivation practices were followed, and the fertilizer used consisted of 83 g of a formula: 30-120-70, per meter lenght at planting, and 33 g of the formula: 50-0-45 per meter lenght as dressing 22 days after germination. The plant population density was 50,000 per hectare. Plants were collected for analysis at 20 days after germination, and there after at intervals of 20 days up to 120 days. The plants were divided into "stems + leaves", tassels, and ears for chemical analysis of Cu, Fe, Mn and Zn. Conclusions: Accumulation of nutrients - Differences in the accumulation of micronutrients appeared before the period of rapid growth (20 days) although afterwards no differences were detectable. - The maximum level of nutrients are attained in the following period (in days): Cu (101 -104); Fe (106-120); Mn (82-94); Zn (87-108). - The maximum quantities taken-up (in mg/plant) are: Cu (2.06-3.49); Fe (26.66- -36.29); Mn (9.92-14.39); Zn (5.88-6.69). Transport of nutrients - The transport of nutrients into the ears of the different cultivars are (per ha harvested): Cu (26-35 g); Fe (200-220 g); Mn (90-140 g); Zn (160-250 g).

The objective of the present work was to examine the differences in nutrients levels between the cultivars Agroceres 256, Agroceres 504, Centralmex, H-7974 and Piranão. The experiment was carried out in the municipality of Piracicaba, State of São Paulo, Brazil. The soil type was a sandy "Regossol" of medium fertility. Common cultivation practices were followed, and the fertilizer used consisted of 83 g of a formula: 30-120-70, per meter length at planting, and 33 g of the formula 50-0-45 per meter length as a dressing. The plant population density was 50,000 per hectare. Sixty days after planting and at flowering the leaves (+4) and the ear leaf, respectively, were harvested for diagnostic purposes. It was observed that differences exist in the concentrations of P, K, Ca, Mg and Fe in the leaf (+4) dry matter of the cultivars at 60 days after planting, and in the concentrations of P, K, Cu and Fe during flowering. Such differences did not affect the production of grain. The extent of the differences between cultivars in the levels of nutrients in the leaves depends on the period of sampling. The harvestry of leaves at determined physiological periods tend to dimi-nuish these differences. Cultivars with similar yield potential may be regarded equally in relation to their leaf analysis, provided that one adopts an adequate range of nutrient levels.

Young cashewnut trees were cultivated in nutrient solutions, in order to identify symptoms of malnutrition. The treatments were: complete solution, -N, -P, -K, -Ca, -Mg and -S. The deficiencies were comproved by chemical analysis of the leaves. The results expressed as percentages in dry matter are:

Young cashewnut trees were cultivated in purify nutrient solutions in order to identify symptoms of malnutrition. The treatments were: complete solution, -B, -Cu, -Fe, -Mn, -Zn, -Mo. The deficiencies were comproved by chemical analysis of the leaves. Chemical composition of the leaves, expressed in ppm, on dry matter basis is:

The objective of the present work was to examine the differences in growth, accumulation and transport of nutrients between cashewnut trees from 1 to 14 years old. The experiment was carried out in the municipality of Santa Terezinha, State of Bahia. The soil type was a sandy oxisol of low fertility, except for K was high. Common cultivation practices were followed. Trees were collected for chemical analysis of N, P, K, Ca, Mg, S, B, Cu, Fe, Mn and Zn. Conclusions: The cashewnut tree presents a continuous growth from 1 to 14 years old. A ten year old cashewnut trees contained: N- 1.5 kg;P- 0.2 kg;K-1.1 kg;Ca- 0.2 kg; Mg- 0.3 kg; S- 0.1 kg; B- 4.0 g;Cu- 1.4 g; Fe- 2.0 g;Mn- 7.8 g;Zn- 2.6 g. One kilogramme of cashewnut fruits transport: N- 13.9 g; P- 1.3 g; K- 6.2 g; Ca- 0.3 g; Mg- 1.3 g;S- 0.5 g;B- 18.5 mg;Cu- 16.2mg;Fe- 36.9 mg;Mn- 13.2 mg. Differences exist in the concentrations of P, K, Ca, B and Mn in the leaves dry matter when trees became olders. No differences exist in the concentrations of N, Mg, S, Cu, Fe and Zn in the leaves dry matter when trees became olders.

The present work was carried out in order to study: a - the effect of omission and presence of the macronutrients and boron on the growth of the plants; b - deficiency symptoms of macronutrients, as well of boron; c - the effect of the deficiency of each nutrient on the chemical composition of the plants. Young spinach plants were grown in pots containing pure quartz sand. Several times a day the plants were irrigated by percolation with nutrient solutions. The treatments were: complete solution and deficient solution, in which each one of the macronutrients was omitted as well boron. Soon as the malnutrition symptoms appered, the plants were harvested and analysed chemically. - symptoms of malnutrition are easily observed for N, K, Ca and B. - symptoms of malnutrition for P, S and Mg are not easily identified. - the nutrient content, in dry matter, in deficient leaves and healthy leaves is:

Spinach plants were cultivated under field conditions. All manegement practice were observed. Periodically plants were harvested and analysed for N, P, K, Ca, Mg, S, B, Cu, Fe, Mn, Mo and Zn. - The variety presented a continuous growth expressed, in dry matter, until 120 days. - The greatest demand for nutrients occurs between 93 and 106 days. - The maximum absorption of the nutrients by leaves is around the period of 93 to 106 days. - The absorption of Fe by the spinach plants is continuous until at the end of the plant life. - At 90 days the spinach leaves presented the following concentration: N- 2.54%; P- 0.21%; K- 5.64%; Ca- 1.06%; Mg- 0.83%; S- 0.35%; B- 66 ppm; Cu- 15 ppm; Fe- 364 ppm; Mn- 297 ppm; Zn- 139 ppm and Mo- 0.83 ppm. - One plant and 22,222 spinach plants (one ha.) remove the following quantities in nutrients:

The initial studies are presented, relative to the experimental part of the method of the 2,2'-dypiridyl ketoxime, for determination of cobalt. The preparation technique of the reagent from the corresponding ketone was presented. The use of 1.0 ml of the 1% reagent solution in 80% ethyl alcohol was suggested, for the determination of up to 10 micrograms of cobalt. The above solution was tested until 90 days after it's preparation, and no alteration was detected. The best pH conditions, for the formation and extration of the colored compound is between 7.0 and 8.0. Among several buffer solutions used, the most efficient was the one prepared with sodium citrate 1 molar, triethanolamina (1+2), in the proportion of 2:1, after ascertaining the pH at 7,8 with 30% citric acid. Studies about solvents, effects of several ions and the application of the method to plant analysis, will be presented later.

Ten gram portions of each soil sample were treated with 4 ml of solutions containing increasing amounts of inert Zn (100, 200, 400, 800 and 1,600 mg) and 0.70 mc of radioactive 65Zn. After 10 and 20 days of incubation, soluble Zn was extracted and the amount of Zn fixed was calculated by mean of the activity found in the extract and in a standard solution. The results obtained from this experiment support the following conclusions: a - in all soils studied, the amount of Zn fixed decreased from the 10th to the 20th; however, the difference was not significant; b - the quantity of Zn fixed increased as the amount of Zn applied increased.

This paper was carried out in order to verify the effects of the clay, silt and sand soil fractions on zinc fixation by soils. Ten grams each of 30 samples of different soils were placed in a 250 ml Erlenmeyer flask and 4 ml of solution containing 100 mg of inert Zn and 0.70 mc of radioactive 65Zn were added. After 20 days of incubation, Zn was extracted with 20 ml of 0.01 M EDTA solution made 1 M with respect to (NH4)2CO3. An aliquot of 5 ml of the extract was transferred to a test-tube and radioactivity of 65Zn in it was measured with a scintillation counter. Quantity of fixed Zn by the different soils was calculated from the data obtained and counting made on the standard solution. It was concluded that clay and silt took part of the Zn fixation by the soil, but not the sand.

The purpose of this experiment was to verify the effects of some properties of the soil as pH, and the content of soluble phosphate and organic matter on the soil capacity to fix zinc. Ten grams each of 30 samples of different soils were placed in a 250 ml Erlenmeyer flask and 4 ml of solution containing 100 mg of inert zinc and 0.7 mcof radioactive 65Zn were added. After 20 days of incubation, Zn was extracted with 20 ml of 0.01 M EDTA solution made 1M respect to (NH4)2CO3. An aliquot of 5 ml of the extract was transferred to a test tub and radioactivity of 65 Zn in it was measured with a scintillation counter. Quantity of zinc fixed by the different soils was calculated from the data obtained and county made on the standard solution. It was concluded that the amount of zinc fixed by the soil was positively correlated with pH, soluble phosphate and organic matter content of the soils.