RCAAP Repository

In order to obtain: a) a clear picture of the deficiencies symptoms of N, P, K, Ca, Mg, S and B; b) the lack of the elements on the dry matter production; c) concentration of the macro and micronutrients on the leaves, stems and roots. Young rubber plants (Hevea brasiliensis L.), were cultivated in nutrients solutions, in which one the following elements were omitted at once: N, P, K, Ca, Mg, S and B. Clear out symptoms were obtained for all macronutrients and boron. The growth rate of the rubber plants were drastically affected by lack of N, K followed by other nutrients. The omission of P from the nutrient solution did not affected the growth of the plants. The levels detected by chemical analysis of the leaves from with symptoms of deficiency and without symptoms of deficiency plants were: N% = 1.94 and 3.40: P% =0.14 and 0.25; K% = 0.79 and 2.22; Ca% = 0.59 and 1.28; Mg% = 0.26 and 0.50; S% = 0.10 and 0.10; B ppm = 31-3 and 171.8.

Basella alba is used as a major food on the Amazon region, north Brazil for its high mineral and vitamins content. The purpose of the present work was: a) obtain a clear picture of the macronutrient deficiency; b) growth of the plants in function of (1); c) analyptical levels found in the leaves. Young Basella alba plants (bertalha in Portuguese) were cultivated in pots containing fine pure quartz and irrigated by percolation with different nutrient solutions lacking one of the element at the time. Clear cut symptoms were obtained for all macronutrients. Only the omission of nitrogen and potassium affect the dry matter production of plants. The range in dry matter for unhealthy and healthy leaves were: N% = 1.25--3-55; P% = 0.17-0.36; K% = 0.46-3.55; Ca% = 0,62-1.78; Mg% = 0.37-0.80; S% = 0.19-0.13.

This experiment was carried out to study the effects of the temperatures of 14, 21 and 28°C on germination of three cultivars of Vigna unguiculata, Phaseolus vulgaris and Glycine max. The seeds where germinated on Petri dishes provided with cotton and filter paper, maintained in incubator with high humidity. The Petri dishes were maintained under controlled temperature conditions. Higher germination was observed at 21°C in relation to temperatures of 14 and 28°C, for Vigna, bean and soybean cultivars. Best germination were showed by 'Carioca' and 'Goiano Precoce' beans,followed by 'Rosinha' bean, 'EPACE 1' Vigna and 'Davis' soybean at 21°C. Vigna cultivars adapted to high temperatures presented problems for germination at 14°C. Normaly velocity of hypocotyl emergence was lower tham velocity of radicle emergence.

O presente ensaio refere-se à adubação de Pinus oocarpa Schiede. Foi instalado em solo Latossolo Vermelho Escuro Distrófico originalmente sob vegetação de cerrado, no município de Assis, São Paulo. Através de medições periódicos de altura e DAP (diâmetro à altura do peito) das árvores, foram verificados os efeitos da adubação NPK, calagem, S, B e Zn sob delineamento experimental de blocos casualizados com quatro repetições. Pela análise estatística dos últimos dados de altura e diâmetro, quando as plantas estavam com 3 anos, conclui-se que: a adubação NPK proporcionou um aumento significativo no desenvolvimento das plantas em altura e diâmetro; a adubação NPK + calagem aumentou significativamente a altura; a adubação NPK + calagem + S aumentou significativamente o diâmetro e a aplicação de B e Zn não apresentou efeitos significativos.

Five (5) experiments, located in the peanut region of the State of São Paulo, Brazil, were installed in big plots, with the aim of studing the effect of lime applied at planting time on two peanut cultivars. Liming at planting time at the rate of 1,230 kg/ha of lime increased yield of the cultivar Tatu (Valencia vegetative type) in one of the experiments. The Tatuí cultivar (spanish vegetative type) gave on response to liming.

Primary objective of this work was to study the growth, and concentration and accumulation of macronutrierts on the Hevea brasiliensis plants, at various ages. Leaves, stems and branches of rubber tree clone Fx 3864 from one year up to years old were collected from a plantation located at the BONAL S.A. farm at Rio Branco, Brasil the soil under the forest was classified as a heavy texture Red-Yellow Latosol. Results obtained showed that: - Highest growth increment occured from the third year on. - The leaves had the highest nutrient concentration - During the fourth year, nutrient extraction per hectare was: N - 24.54 kg, P - 1.82 kg, K - 18.29 kg, Ca - 11.07 kg, Mg - 5-29 kg, S - 1,88 kg. - Total macronutrients were absorbed in the following decreasing order: N, K, Ca, Mg, S, P.

A study was made on early, normal and delayed plaji ting on the oil protein content of the seeds of two late varieties of soybean, UFV-I and I AC-7. The field experiment was carried out at Campinas Experimental Station in eutrophic Latosolo Roxo, during the years 1979/80 and 1980/81. In the first year were made every twenty days starting from October 5 and in the second year every thirty days starting from September 17, the total being eight and seven in the consecutive years. The planting date affect the oil content in both years and varieties. The biggest variations were due the year. Though the planting dates, the variation was aleatory. The planting date affected only the protein content of the I AC-7 variety in both years. The variation was not tendentious thought the planting dates. On early and normal plantings the oil and protein content of the seeds didn't differ for both the varieties.

The efficiency of Catalão Rock Phosphate (FG) was studied in comparison of that of triple superphosphate (ST). Four rates of P2O5were used both in the presence and in the absence of liming. The residual effect was evaluated in two successive crops. The chief conclusions were the following: ST proved to be a better source of P2O5, its effect being increased by liming; P uptake from both sources was increase by liming, especially in the last two croppings; there was a positive correlation between residual P (Olsen) and dry matter production in the same harvests; in the third crop, however, a better correlation was found to exist between soil - Ca and yield than with soil - P and yield.

The efficiency of Catalão rock phosphate (FG) was studied in comparison to that of triple superphosphate (ST) . Four rates of P2O5 were used either in the presence or in the absence of liming. The residual effect was evaluated in two successive crops. The main conclusions were the following: ST was shown to be a better source of P than FG, its eficiency being icreased by liming which also increased P up take from both sources, especially in the second and third crop; method of application of FG had no effect on dry matter yield; there was a positive correlation between residual P (Olsen) and yield; in the third crop, however, a higher correlation coefficient was found to occur with soil Ca.

The response of beans to a partially acidulated (50% sulfuric acid) rock phosphate (FAPS) was studied under greenhouse conditions. Simple superphosphate (SPS), the original rock phosphate (FA), and Gafsa rock phosphate (FG) were used for comparison. The soil was acidic and low in available P. Three successive crops were made to evaluate the residual effects both in presence and in absence of initial liming. Main conclusions were as following. Giving to the dry matter yield obtained with powder SPS the relative value of 100 the efficiency of the other P2O5 sources was: (1) in the absence of liming - granulate SPS = 80 FA = 85, FAPS = 75 to 90 (depending of the granule size), FG = 150; (2) in th, e presence of liming - granulate SPS = 98, FA = 66 FAPS = 70 to 85 FG = 110 Liming increase the uptake of P from all sources. FAPS served as source of Ca and S as well. After the third crop the available (01sen) P content obeyed the following decreasing order: SPS, FG, FAPS, and Fa. Respective of source the P content was lower when lime had been applied.

The efficiency of a partially acidulated rock phosphate, FAPS, was studied using bean as a test crop in a Dark Red Latosol low in P and acidic. For comparison ground rock phosphate, from Araxá, MG, Brazil (FA) and from Gafsa (FG) , and simple superphosphate, either powder or granulated (SPSP and SPSG, respectively) were employed. Three successive croppings were conducted in order to estimate the residual effect of the P2O5sources. As subtreatments initial liming and no liming were used. The statistical analyses of the data allowed for the following conclusions to be drawn, taking into account the dry matter production observed in the three harvests, and making the yield obtained at the expenses of SPSP equal to 100: (1) in the absence of liming - SPSG = 100, FA = 60 to 85 (depending upon granule size), FG = 132; (2) in the presence of liming - SPSG = 105, FA = 52, FAPS = 75 to 90, FG = 95. Irrespective of source of P2O5 liming increased the absorption of P only on the third crop. FAPS acted also as source of Ca and S. Liming decreased residual available (Olsen) P determined after the third cropping except in the case of the treatment with larger granules. The available residual P obeyed the following decreasing order: SPS, FAPS, FG and FA. It is considered that FAPS behaved in a way closer to that of the SPS.

The usefulness of a rock phosphat from Araxá, MG, Brasil, partially acidulated with sulfuric acid (FAPS) was studied, rock phosphate (FA), gafsa phosphate (FG), and simple superphosphate (SPS) being used for comparison. There successive crops were employed in order to assess the residual value, both in presence an in the absence of liming. The analyses of data obtained allowed for the following conclusions to be drawn: the efficiency of FAPS in relation to that of SPS decreased from the first to the third crop, reaching 70% as general ave rage; in the presence of liming, however, the efficiency did not decrease so much, 80-90% being obtained; FG gave results equivalent to those obtained with SPS; liming decreased the relative efficiency of the rock phosphates, especially that of FA which fell from circa 50% to 40%; available P content in the soil was increased as consequence of varions treatments including FAPS plus lime; FAPS acted as a source of P, Ca, and S; its performance in closer to that of SPS than to that of the original FA.

The response of sweet sorghum to a partially acidulated (with sulfuric acid) rock phosphate (FAPS) was studied using the original ground phosphate (FA), Gafsa rock phosphate (FG) and simple superphosphate (SPS) for comparison. The soil, a Dark Red Latosol (LE, Haplorthox) was collected in Botucatu, SP. Three successive crops were conducted without new applications of P sources, both in the presence and in the absence of initial liming. The analyses of the data obtained allowed for the following conclusions to be drawn: in the three successive crops combined, dry matter production in the presence of FAPS and no lime applied was 71% of that obtained when powder SPS was used; the efficiency of FA was 17%, where as that of PG was 150%; In the presence of liming,, however, the following values were obtained: granulated SPS - 89%; FAPS - 98%; FA = 30%; FG = 83%. Liming increased the uptake of P from powder SPS, FA and FAPS. FAPS acted also as source of Ca and S. After the third crop, in the absence of liming, SPS left In the soil the highest concentration of available P (Olsen), being followed by FG, FAPS and FA. Liming, however, decreased the amount of residual available P due to SPS, FA, and FG. In the whole the behaviour of FAPS was more similar to that of SPS than to the effect of PA.

As a rule, soils of the subtropical and tropical regions, in which rainfall is not limiting, are acidic, and low in phosphorus, and, to a less extent, in other macro and micronutrients as well, such a sulfur, boron and zinc. The establishment of a permanent agricultural prac. tice therefore, demands relatively high usage of liming and phosphatic fertilization, to begin with. Several approaches, not mutually exclusive, could be used in order to increase the efficiency of utilization of soil and fertilizer phosphorus so that, goal of diminishing costs of production is reached. The use of liming materials bringing up pH to 6.0-6.5 causes the conversion of iron and aluminum phosphates to more available calcium phosphates; on the other hand, by raising calcium saturation in the exchange complex, it improves the development and operation if the root system which allows c or a higher utilization of all soil nutrients, including phosphorus, and helps of stand water deficits which may occur. The role of mycorrhizal fungi should be considered as a way of increasing soil and fertilizer P utilization, as well as the limitations thereof. Screening of and breeding for varieties with higher efficiency of uptake and utilization of soil and fertilizer phosphorus leads to a reduction in cost of inputs and to higher benefit/cost ratios. Corrective fertilization using ground rock phosphate helps to saturate the fixation power of the soil thereby reducing, as a consequence, the need for phosphorus in the maintenance fertilization. Maintenance fertilization, in which soluble phos-phatic sources are used, could be improved by several means whose performance has been proved: limimg, granula tion, placement, use of magnesium salts. Last, cost of phosphate fertilization could be further reduced, without impairing yields, through impairing yields, through changes in technology designed to obtain products better adapted to local conditions and to the availability or raw materials and energy sources.

The comparative response of three sorghum (E-57, TEY 101 and C- 102) and of three corn cultivars (HMD-7974, Centralmex and Piranão) to N, P and K applications was studied in a soil from Anhembi, SP, classifield as Distrophic quartz sand (AQd) was studied. Leaf analyses were made to assess the nutritional status of the two crops. Main conclusions were the following. 1. Sorghum yieldel more than corn; 2. Both sorghum and corn varieties showed different capacities to absorb N, P and K from the soil and to fertilizer application; 3. There was no response to K2O fertilization; 4. Only Piranão increased yield when suplemented with a mixture of micronutrientes; 5. Direct relationships between rates of N and P2O5 and yield and leaf content were found; 6. Direct relationships between rates of N and P2O5 and yield and leaf content were found; 7. The following leaf levels were considered to be adequate, respectively for sorghum and corn: N - 2,00 - 2,25%, 3,25 - 3,50%; P - 0,30 - 0,40, 0,45 - 0,50; K -2,00 - 2,50, 2,20 - 2,40%; Ca - 0,20 - 0,40, 0,44- 0,72% Mg - 0,25 - 0,40, 0,34 - 0,60%; S - 0,50 - 0,70, 0,72 -0,80; Cu - 7 - 10, 11 - 15%; Fe - 84 - 170, 98 - 125%; Mn - 58 - 72, 66 - 85%; Zn - 10 - 14, 18 - 22; critical levels, however, do very depending upon cultivar.

Rice plants cultivar L-45, a mutant obtained by Dr. A. Ando, Piracicaba, were grown in nutrient solution until maturity. At intervals, fixed to coincide approximately with physiological stages of development, samples were taken for analysis of dry matter production and nutrients accumulation. It was verified that maximan rate of uptake occurred from 64 to 106 days after germination which corresponds to full tillering and beginning of maturation. Nutritional requirements obeyed the following depreasing order: macronutrients - N, K, Ca, P, Mg and S; micronutrients - Mn, Fe, Zn, Cu and B. Export of macronutrients occurred in the same order, were as in the case of micronutrients it was: Mn, Zn, Fe, Cu, and B.

Rice plants were grown in complete and deficient nutrient solutions, with respect to macronutrients. Growth was affected by lack of N, P and Mg only. The concentration of the elements in dry matter, however, was affected by the treatments. Both leaf analyses and quick tissue tests showed to be adequate to show variations in mineral composition in response to the omission of either N, P on K from the substrate. Foliar nitrate reductase activity decreased when any element, except Ca (increase) was lacking.

Root and leaf uptake of P32 was studied using upland rice cultivars, namely: L-45, Dourado Precoce and Penatie. Significant differences in absorption were observed among varieties. Except in the case of L-45 in_ tact plants were able to absorb more phosphorus than excised roots. The dual mechanism of absorption was observed, one operating within the range of 1-5 umoles in the external solution and the second one in that of 10² to 10(4) micromoles. When added to the solution of either monoammonium or diammonium phosphate urea increased foliar uptake. In the presence of the second source urea helped the transport to other organs of the plant. Highest rate of long distance transport was observed in the case of cv. Penatie, the lowest taking place in the variety Dourado Precoce.

Rice plants, Dourado Precoce, were grown in nutrient solution in order to study its nutritional requirement as well as the accumulation of dry matter and macro and micronutrients (excet Mo) during the life cycle. Demand for mineral elements followed the following decreasing order: macronutrients -K, N, Ca, Mg and S; micronutrients - Fe, Mn, Cu, Zn and B. Dry matter yield reached a maximun 100 days after germination (DAG), whereas accumulation of elements showed the geghest values at largest (140 DAG).

A variedade Dourado Precoce foi cultivada em solução nutritiva completa e com deficiência de macronutrientes.A produção de matéria seca total, avaliada antes do fim do ciclo, não foi diminuida pela carência de Ca, Mg e S. De um modo geral os teores encontrados na matéria seca foram maiores no tratamento completo. Através de diagnose foliar feita no perfilhamento estabeleceram-se níveis adequados e deficientes de macronutrientes. Foi verificado que os testes rápidos notecido foliar para N-NO3-, P-H2PO4 e K+ solúvel dão indicações do estado nutricional. A atividade da redutase de nitrato foliar foi reduzida significativamente pela deficiência de todos os elementos.