RCAAP Repository

Two methods for solubilization of agricultural limestone samples for determination of calcium and magnesium were studied. One method, supported on vigorous acid digestion, is indicated for determination of the total of those elements; and another one, simple and rapid, is used in routine laboratories; both were applied to different granulometric fractions of the samples. The results, statisticaly analysed, did not show significative differences between both methods as well as between calcium and magnesium oxide percentages contained in the different granulometric fractions that compose the commercial limestones. The simplified solubilization method is indicated to characterize soluble calcium and magnesium oxides in agricultural limestones.

The analytical method is applied in locating pyroxene optical indicatrices, in thin sections, in the universal stage. Eight extinction operations were carried out for each section, with Φ= 45°, 135°, 225° and 315°. The main conclusion is that the analytical method may be used as a routine procedure in determining the optical properties of these minerals.

This study was conducted to determine residual effect of eight phosphate fertilizers on two soils of low phosphorus content, using corn (Zea mays L.) as test crop. The experiments were carried out in greenhouse. Dry matter yields and amount of N, P and K uptaken were used to evaluate fertilizer effectiveness. The results indicated that the fertilizer with best residual effect were calcium metaphosphate and potassium metaphosphate, followed by thermophosphate and Olinda rock phosphate in regosol. There were no significant difference for dry matter yield in latosol, but in general the calcium metaphosphate, Olinda rock phosphate and potassium metaphosphate gave best results. The fertilizers with lowest residual effect were those with high content on water soluble phosphorus: triple superphosphate, ordinary superphosphate, DAP and ammonium poliphosphate.

A glasshouse experiment was carried out in order to test the effects of phosphorus (150 ppm P2O5) basic amendment (150 ppm P2O5, 50 ppm K2O and micronutrients) and lime (1 ton CaC0(3)/ha) in the nodulation by natural strains of Rhizobium in dry bean (cultivar Carioca), in 4 different soils of São Paulo State: Mediterraneo, Podzolizado and two Terra. Roxa Estruturada. The nodule dry weight incrased in two soils (Mediterraneo and Podzolizado) due to phosphorus addition, and in Terra Roxa Estruturada due to addition of phosphorus plus lime. The treatment PK + micronutrients provided better plant development, even in the absence of lime, indicating effect of micronutrients and potassium in the soils studied. However, in Terra Roxa soils, the addition of phosphorus was sufficient to increase the foliage dry weight and total N. The total N increased in plants treated with the basic fertilization. The phosphorus addition contributed to a better nodulation (nodule dry weight and number) by natural strains of Rhizobium.

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The aim of this work was to study in greenhouse conditions the effects of two levels of iron and zinc on yield and chemical composition of common bean (Phaseolus vulgaris L.) and on atmospheric nitrogen fixation, in three soils, classified as Terra Roxa Estruturada (TRE), Latossol Vermelho Escuro (LVE), and Podzolico Vermelho Amarelo (PVA). The coefficient of utilization of these micronutrients by this crop and its distribution in above-ground parts and roots were also assessed. The rates for iron were 1.5 and 3.0 ppm, and for zinc, 2.5 and 5.0 ppm. It was applied 7.5 µCi of 59Fe/kg of soil with the lower rate of the stable iron, and 5.0 and 10.0 µCi of Zn/kg of soil in the pots corresponding to the lower and higher rate of the stable zinc, respectively. The plants were harveste at the age of 60 days and nitrogen, phosphorus, potassium, iron and zinc contents were determined. Immediately after harvest, symbiotic nitrogen fixation was assessed, using the acetylene reduction method. The detection of 59Fe and 65zn radioactivity were carried out on nitric percloric extract, by gamma ray spectrometry. The behavior of common bean presented high variation among the three soils, for all the variables. There was no influence of treatments of iron and zinc on dry matter of above ground part and root and also on the weight and number of nodules. The rate of 3.0 ppm of iron decreased the capacity of nodules to fix atmospheric nitrogen in relation to rate of 1.5 ppm, while the rate of 5.0 ppm of zinc increased this capacity, in relation to the rate of 2.5 ppm. There was significative effect of treatments on nitrogen, potassium and zinc contents in above ground part and on nitrogen and zinc contents in the root. The absorption of zinc from the fertilizer and the percentagem of zinc in the plant derived from fertilizer were diretly influenced by rate of zinc The higher coefficient of utilization of zinc from the fertilizer was 4.0%.

This research deals with the effects of exogenous growth regulators on dry weight, water contents, soluble carbohydrates, and reducing sugars contents of cotton plants. To study the influence of the chemicals, cotton seeds were immersed during 22 hours in water solutions of (2-chloroethyl) trimethylammonium chloride (CCC) at concentration of 2000 ppm, succinic acid -2,2-dimethylhydrazide(SADH) 4000 ppm, gibberellic acid (GA) 100 ppm, indolylacetic acid (IAA) 100 ppm, and water as check treatment. CCC 2000 ppm reduced the dry weight and increased the water contents in the foliage (leaves) of cotton plants. This growth retardant reduced the soluble carbohydrates contents in the plant foliage. Gibberellic acid 100 ppm promoted increases in reducing sugars contents in cotton plants and IAA 100 ppm caused reduction in reducing sugars contents.

This paper deals with an experiment carried out in pots with the aim of studying the fixation of P in a Dark Red Latosol, from the Municipality of Piracicaba, State of Sao Paulo, Brazil. The main conclusions were as follows: a) about 90% of the fixed P remained soluble in 0,05N H2SO4 solution; b) Fe and Al contributed to increase the quantities of fixed P; c) the pre-treatment of the soil with Ca(H2PO4)2. H2O decreased its capacity for fixing P.

Plants of Chrysanthemum leucanthemum grown in pots with soil under greenhouse conditions, were sprayed with growth regulators twice, in May and June, to study the development of the plants in October. Succinic acid-2,2-dimethylhydrazide (SADH) at concentrations of 1250, 2500 and 5000 ppm, (2-chloroethyl) trimethylammonium chloride (CCC) 2000 ppm, (2-chloroethyl) phosphonic acid (CEPA) 320 ppm, maleic hydrazide (MH;) 1000 ppm, gibberellic acid (GA) 50 and 100 ppm, indolylacetic acid (IAA) 100 ppm, and water as check treatment, were applied. MH 1000 ppm reduced the number of leaves and stems. SADH treatments reduced the shoot growth and the number of stems. Applications of IAA 100 ppm promoted the formation of higher number of leaves and stems in Chrysanthemum leucanthemum. It was seen that sprays with GA at a concentration of 100 ppm elongated shoots.

In order to find out the concentration of macro and micronutrients, as well, the total amounts of nutrients absorved by Solanum gilo, var. Morro Grande Oblongo, plants were collected from field from 30 days up to 180 days and analysed for the elements. At the flowering stage the leaves presented the following concentration: N-0.55%; P-0.30%; K-2.00%; Ca-1.21%; Mg-0.22%; S-0,27%; B-50 ppm; Cu-11 ppm; Fe-774 ppm; Mn-69 ppm; Mo-0.5 ppm; Zn-22 ppm. A production of 9 M.T./ha. effective harvested content: N-26 kg.; P-4 kg.; K-24 kg.; Ca-5 kg.; Mg-2 kg.; S-2 kg.; B-25 gr.; Cu-17 gr.; Fe-89 gr.- Mn-37 gr.; Mo-0.8 gr.; Zn-34 gr..

This research deals with the effects of exogenous growth regulators on dry weight, contents of aminoacids and phenolic compounds in leaves of cotton plants. To study the influence of the chemicals, cotton seeds were immersed during 22 hours in water solutions of (2-chloroethyl) trimethylammonium chloride (CCC) at concentration of 2000 ppm, succinic acid-2,2-dimethylhydrazide 4000 ppm,gibberellic acid 100 ppm, indolylacetic acid (IAA) 100 ppm, and water as check treatment. CCC 2000 ppm increased the dry weight in the leaves of cotton plants. This growth retardant increased the content of free aminoacids in cotton leaves. IAA 100 ppm reduced the concentration of aminoacids in the treated plants. The contents of phenolic compounds in leaves of cotton was increased by CCC, in relation to check treatment.

Lily bulbs were held at 22°C or vernalized at 4° or 8°C for two weeks and then soaked for 12 hours in 1,000 ppm gibberellic acid (GA) or 1,000 ppm indolylacetic acid (IAA) before being planted in the field. Treatment of lily bulbs with 4°C for two weeks delayed shoot emergence. This delay by vernalization was removed when bulbs were soaked for 12 hours in 1,000 ppm GA or IAA. Vernalization and plant regulators had no consistent effects on the plant height or on the plant quality. Bulbs vernalization at 4° or 8°C for two weeks reduced the number of stems produced. There were no differences in the dates of anthesis between the treatments. Flower quality was improved by bulb vernalization at 8°C for two weeks or by immersion for 12 hours in 1,000 ppm IAA.

Three levels of phosphorus (0.0, 16.0 and 32,0 ppm), boron (0.0, 2.0 and 4.0 ppm), zinc (0.0, 3.0 and 6.0 ppm) and two levels of lime (0.0 and 6.0 gr. CaCO3+2.5gr,MgCO3) were applied to 8.0 kg of an Orthorx soil, originated from a "Cerrado" area from Itirapina (SP), Brazil. A factorial experiment, consisting of 3³ x 2 with two replications was conducted in a green-house at Piracicaba (SP), Brazil. The application of boron and zinc increased the concentration of these elements in the plant tissues. The application of 2.0 ppm and 4.0 ppm of boron to the soil was toxic for the Eucalyptus plants. The application of lime decreased the concentration of zinc, in the plant tissues.

In order to obtain a clear picture of the deficiency and toxicity symptoms of boron, young Eucalyptus grandis plants were grown in nutrient solution in the absence and increasing levels of B (0; 0,125; 0.500; 1.000; 2.000 and 4.000 ppm). Chemical analysis were run for N, P, K, Ca, Mg, B, Cu, Fe, Mn and Zn in order to discover any interference of boron. The symptoms of malnutrition of boron were easily identified. Symptoms of boron toxicity were uncertain. Practically, no interference of boron on the other nutrients was observed. Malnutrition symptoms were associated with a concentration of 46 ppm of boron in the young leaves. Toxicity became visible with 100 ppm of boron in the mature leaves. The "critical level" fitted with 61 ppm of boron in the young leaves.

Gladiolus corms were held at 22°C or vernalized at 4° or 8°C for two weeks and then soaked for 24 hours in 1,000 ppm gibberellic acid (GA) or 1,000 ppm indolylacetic acid (IAA) before being planted in the field. There were no differences in the period of time for shoot emergence among the treatments. Treatment of gladiolus corms with 4°C for two weeks increased plant height in relation to storage at 22°C (control). Gladiolus corms soaked for 24 hours in 1,000 ppm GA reduced the number of leaves of the plants, and corms vernalization at 4°C for two weeks increased the number of leaves. Corms vernalization at 4° or 8°C for two weeks improved plant quality. There were no differences in the dates of anthesis among the treatments. Flower quality was improved by corm vernalization at 4° or 8°C for two weeks.

Sweet sorghum cv Brandes was grown in nutrient solution under stress of macro and micronutrients, as well as in the presence of toxic levels of Al, Cl and Mn. Symptoms of deficiency were observed in all cases, with the possible exception of Cu. Toxicity symptoms of the elements tested were also observed. As a rule, there was good agreement between abnormalities induced with those described in the literature for cereals. Dry matter production was affected in the following increasing order: -S = - Cu = - P = complete, -B, -Zn, -K, -Mo, -N, excess Mn, -Mg, excess Cl, -Fe, excess Al and -Ca. The following leaf contents correspond to deficiency level: N - 1.87%, P-0.14%, K-0.73%, Ca-0.40% (lower leaves) and 0.66% (upper leaves); S-0.16%; B-32 ppm (lower leaves) and 15 ppm (upper leaves), Cu-8 ppm; Fe-157 ppm (lower leaves) and 162 ppm (upper leaves); Mn-339 ppm (lower leaves) and 144 ppm (upper leaves); Mo-0.54 ppm; Zn-16 ppm. Leaf contents associated with toxicity symptoms were: Al-640 ppm; Cl-3.85%; Mn-1440 ppm, and, 1220, 2.37% and 445 ppm, respectively for lower and upper leaves. Nutrient requirements of weet sorghum were estimated to be in kg/ha: N-89.0, P-10.2, K-91.5, Ca-31.5, Mg-18.1, and S-11.6; in g/ha: B-90.0, Cu.61.0, Fe-1,704.0, Mn-256, Mo-2-4, and Zn-146. Only N and K significantly affected ethyl alcohol yield.

This paper deals with the following aspects of the phosphatic nutrition of sweet sorghum: absorption of radiophosphate as influenced by time of uptake and external concentration; comparative foliar absorption of monoammonium and diammonium phosphate both in the presence and absence of urea; redistribution of previously absorbed and stored phosphate. Data obtained herewith allowed for the following conclusions to be drawn: (1) root absorption increased with time of contact, being higher in the case of excised when compared to roots in intact plants; (2) Michaelis and Menten kinetics are applicable to root uptake, the parameters being different for the two types of root material; (3) the two ammonium phosphates showed the same rate of uptake, which was not influenced by urea; (4) P deficient plants showed highes rates of uptake and translocation.

Sintomas de deficiências de macro e micronutrientes foram induzidos nas variedades de Vigna sinensis "pitiúba" e "dorminhoco* cultivando-as em solução nutritiva com omissão de um elemento de cada vez. Embora os sintomas, de modo geral, concordem com os descritos na literatura para outros feijões, observou-se diferença varietal na susceptibilidade às carências.

Vigna sinensis, varieties "Dorminhoco" and "Pitiúba", was grown in nutrient solution in the presence and absence of macronutrients; leaves (upper and lower) were collected for analysis at the and of the life cyle or when symptoms of deficiency were marked. Variations found in leaf composition agree, as a rule, with what is contained in the literature with regards to other species under the same type of experimental conditions: reduction in concentration in the tissue when the element was absent from the substrate; interionic, counter ion, and dilution effects. The following levels of macronutrients were associated with maximun growth: N=1.97 ± 0.16; P=0.14 ±0.03; K= 3.20 ± 0.36; Ca=5.38 ± 0.41; Mg=0.66 ± 0.14; S=0.15 ± 0.04. As indication of deficiency, on the other hand, the corresponding leaf contents would be: N =1.28 ± 0.13; P = 0.02 ± 0.01; K=0.64 ± 0.10; Ca=1.79 ± 0.24; Mg=0.14 ± 0.05; S=0.05 ± 0.01. Due to the large differences found between foliar composition in the control and the deficient plants it is very likely that under field conditions deficiencis may occur when the level of a given element in the leaves is higher than those presented herein. Dry matter was affected in the following decreasing ords: Complete, -S, -Mg, -P, -K, -Ca, -N; therefore, the lowest yield was obtained in the treatment lacking nitrogen.

Vigna sinensis, varieties "Dorminhoco" and "Pitiúba" were grown in nutrient solution both in the presence and in the absence of micronutrients dry matter production was measured either at the end of life cycle or whenever symptoms of deficiency were sufficiently acute to warrant an early harvesting; leaves were then analysed for mineral composition. Dry matter production obeyed the following decreasing order: Complete >; - Mn = - Mo = - Cu >; - Zn >; - B; pods were formed and filled in all treatments except the last two; yield, however, was much lower than in the full strength solution which gave an average equivalent to 1.5 ton per hectare of dry beans. Leaf analyses showed consistently that lack of a nutrient in the substrate leads to a decrease in its contents in the tissue. Other variations were induced in leaf composition by the different treatments being all of them in agreement with common cases of dilution and interionic effects on uptake and in translocation. The inverse relationship between Fe and Mn, however was not substantiated. Tentatively the following leaf levels (in ppm) could be considered as satisfactory: B = 203 ± 31; Cu = 6±0.79; Fe = 817 ± 103; Mn = 148 ± 21; Mo = 0.24 ± 0.05; Zn = 43 ±9; deficient levels could be considered: B = 44 ± 25;Cu=5±1.2; Fe = 337 ± 31; Mn = 24 ± 6; Mo = 0.20 ± 0.08; Zn = 24 ± 5.