154 resultados para Potassium fertilizers
Resumo:
The status of zinc in sugar cane, variety Co 419, troughout its life cyle, was studid in samples cut monthly, from the 6th to 15th month, from an experiment carried on under the conditions of soil and climate prevailing in Piracicaba, State of São Paulo, Brazil. The experiment consisted of 6plots, 3 fertilized and 3 unfertilized. The fertilized ones received 40 kg of N (ammonium sulfate), 100 kg P2O5 (superphosphate) and 40 kg K2O (potassium cloride) per hectare, just before planting. The zinc content was determined by the Zincon method, after separation of zinc from other ions by means of the ion Exchange Resin III, Merck. The results obtained show that there was a tendency to decrease the zinc level in the stalks, whereas it kept more or less constant in the leaves; there was an exception in January, when the zinc level in the stalks had a sharp raise: 38-90-20 and 28-60-23 ppm for the fertilized an unfertilized treatments. There was a parallelism in the absorption of zinc by the plants from 4 hills of both treatments, through the whole - plantcycle but, the total amount taken up was higher with the fertilized plot due to its greater mass production.
Resumo:
Pineapple plants when grown in the greenhouse by the sand culture technique in order to study the effects of deficiencies of macronutrients in growth, yield, leaf and fruit composition, the main results were the following. As a result of the several treatments, yield decreased in the order: Complete Minus Mg Minus S Minus Ca Minus K; nitrogen and phosphorus deficiente plants did not bear fruit. Leaf analyses (see Table 5-1) showed that the ommission of given element from the nutrient solution always caused a decrease in its level in the green tissue. As seen in Table 5-2 the lack of macronutrients had certain effects on fruit composition: acidity increased in all cases excet in the minus Mg fruits; ash usually decreased reaching its lowest valued in fruits from the minus K plants; when compared to fruits picked in the "normal" plants, those lacking K showed a marked decrease both in brix and in total sugars as well; sulfur deficiency also brought a net reduction in the sugar content. Table 5-1. Levels of macronutrients found in pinapple leaves. Elements Treatment Percent of dry matter Nitrogen (N) Complete 1.29 Minus N 0.78 Phosphorus (P) Complete 0.12 Minus P .05 Potassium (K) Complete 2.28 Minus K 0.16 Calcium (Ca) Complete 1.19 Minus Ca 1.10 Magnesium (Mg) Complete 0.41 Minus Mg .29 Sulfur (S) Complete 1.00 Minus S .65 Table 5-2. Effects of macronutrients deficiency in yield and fruit characteristics. Treatment Ave. weight of Acidity As per Brix Total sugars fruits (gm) per cent cent per cent Complete 1.031 1.16 0.40 14.7 10.8 Minus N no fruit was produced Minus P no fruit was produced Minus K 246 1.44 0.26 11.9 8.3 Minus Ca 513 1.40 0.35 17.8 14.3 Minus Mg 957 0.97 0.38 15.4 13.0 Minus S 576 1.42 0.46 17.1 6.5
Resumo:
The authors carried out 3 experiments on the sampling of sugar cane for technological determinations, one with each of the varieties Co 419, CB 40-69 and CB 41-58, in Piracicaba, State of São Paulo, Brasil. The main intent of the project was to compare 2 methods of sampling, namely: 1) Method A, where the sample is a hill (CATANI et al, 1959) or, more generally, 20 stalks all together in a randomly selected point of the furrow; 2) Method B, where 20 stalks are taken, from 20 points evenly spread but on the whole plot. Coefficients of variation for 20 stalk samples Variety Characteristic 20 stalks per hill 1 stalk per hill Brix 4.8% 1.9% Pol 6.4% 2.5% CB 40-69 Coefficient of purity 2.1% 0.83% Available sucrose 7.3% 2.7% Weight 6.6% 6.9% Brix 5.3% 1.8% Pol 7.6% 2.6% Co 419 Coefficient of purity 2.9% 1.0% Available sucrose 8.6% 3.0% Weight 21.2% 6.5% Brix 2.8% 1.4% Pol 4.1% 1.9% CB 41-58 Coefficient of purity 1.8% 0.8% Available sucrose 5.0% 2.2% Weight 10.9% 6.2% For the 3 varieties studied and for the data on Brix, pol, coefficient of purity, available sucrose and weight, analyses of variance were carried out. Further computations led to the following coefficients of variation. For available sucrose, which is probably the most important characteristic studied, the average coefficient of variation for the 3 varieties was 2.7%, for the case of method B, that is, 20 stalk samples, one stalk per hill. Assuming this coefficient of variation, in a trial with 5 treatments and 6 replications, in randomised blocks, the least significant difference among treatment means, at the 5% level, would be 4.7% of available sucrose by Tukey's test, and 3.3% by the t test. For the case of method A the average coefficient of variation is 7.0% and, in similar conditions, the least significant difference would be 15.1% by Tukey's test, and 12.1% by the t test. Since differences of available sucrose among treatments in experiments with fertilizers seldom are higher than 3 or 4% of the mean (PIMENTEL GOMES & CARDOSO, 1958), method B with a 20 stalk sample per plot gives more or less the minimum amount of cane to be sampled for technological determinations. In experiments with varieties, however, where differences may be assumed to be higher, a sample of 10 to 20 stalks one per hill, can be enough.
Resumo:
This paper describes the results obtained from the determination of iron in sugar cane according to the age of the plant, in the soil and climate conditions of the state of S. Paulo, Brazil. The iron was determined by 1-10- phenanthroline method, in samples cut monthly from 7th to 15th month from an experiment consisted de 3 plots fertilized with amonium sulfate, superphosphate and potassium cloride. The concentration of iron in the stalks and in the leaves varies according to the age of the plant. A ton of fresh stalks 15 months old contains 78,71 g of iron.
Resumo:
In this paper the authors describe the results obtained from the determination of molybdenum in sugar cane plant, grown in soils and climate prevailing in Piracicaba, State of São Paulo, Brazil. The molybdenum was determined in samples cut monthly from the 8th to 14th month, from an experiment consisting of 6 plots, 3 fertilized and 3 unfertilized. The fertilized treatment received 40 kg N (ammonium sulfate) 100 kg P2O3, (superphosphate) and 40 kg K2O (potassium chloride) per hectare, just before planting. Molybdenum was determined by thiocyanate-stannous chloride method, using carbon tetrachloride-butyl alcohol misture, for extrating the colored complex. The results obtained show a parallelism in the absorption of molybdenum by the plants of both treatments. The concentration of molybdenum in the stalks have a tendency to decrease, where as it kept more or less constant in leaves, with a exception in the 14° month when it rised probable because of a migration of molybdenum of the stalks to the leaves. The total amount molybdenum taken up was higher with the fertilized plot due its greater mass prodution.
Resumo:
Sand culture experiments, using a sub-irrigation technique, were installed in order to find out the effects of the macronutrients N, P, K, Ca, Mg and S on growth, aspect, mineral composition, length of fibers, thickness of cell wall and cellulose concentration in slash pine. The aim was to obtain, under controlled conditions, basic information which could eventually lead to practical means designed to increase the rate of growth and to make of slash pine a richer source of cellulose. Nitrogen, Phosphorus, Potassium Experiment A 3 x 3 x 3 factorial design with two replicates was used. Nitrogen was supplied initially at the levels of 25, 50 and 100 ppm; phosphorus was given at the rates of 5, 10 and 20 ppm; potassium was supplied at the rates of 25, 50 and 100 ppm; six months after the experiment was started the first level for each element was dropped to zero. Others macro and all micronutrients were supplied at uniform rates. Fifteen hours of illumination per day were provided. The experimental technique for growing the slash pine seedlings proved quite satisfactory. Symptoms of deficiency of nitrogen, phosphorus and potassium were observed, described and recorded in photographs and water colors. These informations will help to identify abnormalities which may appear under field conditions. Chemical analysis of the several plant parts, on the other hand, give a valuable means to assess the nutritional status of slash pine, thus confirming when needed, the visual diagnosis. The correctness of manurial pratices, on the other hand, can be judged with the help of the analytical data tabulated. Under the experimental conditions nitrogen caused the highest increases on growth, as measured by increments in height and dry weights, whereas the effects of phosphorus and potassium were less marked. Cellulose concentration was not significantly affected by the treatments used. Higher levels of N seemed to decrease both length of fiber elements and the thickness of cell wall. The effects of P and K were not well defined. Calcium, Magnesium, Sulfur Experiment A 3 x 3 x 3 factorial design with two replicates was used. Calcium was supplied initially at the levels of 12.5, 25 and 50 ppm; magnesium and sulfur were given at the rates of 6, 12.5 and 25 ppm. Other macro and micronutrients were supplied at uniform rates, common to all treatments. Three months after starting the experiment the first level for each element was dropped to zero. Symptoms of deficiency of calcium, magnesium and sulfur were observed, described and recorded as in the case of the previous experiment. Chemical analysis were made, both for mineral content and cellulose concentration. Length of fibers and thickness of cell wall were measured. Both calcium and magnesium increase height, sulfur failing to give significant response. Dry weight was beneficially affected by calcium and sulfur. The levels of calcium, magnesium and sulfur in the needles associated with deficiency and maximum growth are comparable with those found in the literature. Cellulose concentration increased when the level of sulfur in the substrate was raised. The thickness of cell wall was negatively affected by the treatments; no effect was observed with regards to length of fibers.
Resumo:
This paper deals initially with the role of mineral fertilizers in increasing agricultural production: the relationship between the two variables is illustrated within global, regional national and local contexts. The pattern and trends in fertilizer usage in Brazil are presented next, namely: increase in consumption in the period 1950/72; regional distribution; consumption as related to crops and cultivated land. It is shown that in less than a quarter or century fertilizer use has increased in the country nearly 12 fold, whereas world consumption was raised 7 fold, thus exceeding estimates based in several criteria. Steps taken to secure the raise in fertilizer consumption above the historical trend are discussed: research experience for outlining fertilization recomendations; the transfer of the knowledge to the farmer by the extension work both official and private; the credit policy and special incentives for the purchase of fertilizer; the national policy for minumum proces of agricultural products; the implantation of a national fertilizer industry. It is considered that the Brazilian experience adapted to similar local conditions in other developing countries, presents a possibility for achieving beneficial results without inflationary reflexes in the economy.
Resumo:
An experiment was carried out in order to determine the effect of day time of foliar spraying of several levels of nitrogen fertilizers, N-P-K-S station, and its components on common bean leaves. Results, based on the visual observations, indicated the maximum levels of each fertilizer that did not cause injuries and showed that the foliar spraying early in the morning is the best day time.
Resumo:
An experiment was carried out with common bean (Phaseolus vulgaris, L.) in a Red Yellow Latossol, sandy phase, in order to study the influence of foliar spraying of the Hanway nutrient solution (NPKS) at grain filling stage on: 1) grain yield; 2) the uptake of fertilizer and soil nitrogen by this crop through the root system and 3) the efficiency of utilization of the nitrogen in the foliar spray solution by the grain. The results of this experiment showed that the foliar application of the Hanway solution with ammonium nitrate at the pod filling period caused severe leaf burn and grain yield was inferior to that of the plants which received a soil application of this fertilizer at the same stage. These facts can be attributed to the presence of ammonium nitrate in the concentration used. The composition of final spray was: 114,28 Kg NH4NO3 + 43,11 Kg potassium poliphosphate + 12,44 Kg potassium sulphate per 500 litres. The uptake of nitrogen fertilizer through the root system and the efficiency of its utilization was greater than that through the leaves.
Resumo:
(1) In the period 1965/77 fertilizer consumption in Brazil increased nearly fifteen foild from circa 200,000 tons of N + P2O5 + K2O to 3 million tons. During the fifteen years extending from 1950 to 1964 usage of the primary macronutrients was raised by a factor of 2 only. (2) Several explanations are given for the remarkable increase, namely: an experimental background which supplied data for recommendations of rates, time and type of application; a convenient governmental policy for minimum prices and rural credit; capacity of the industry to meet the demand of the fertilizer market; an adequate mechanism for the diffusion of the practice of fertilizer use to the farmer. (3) The extension work, which has caused a permanent change in the aptitude towards fertilization, was carried out in the traditional way by salesmen supported by a technical staff, as well as by agronomists of the official services. (4) Two new programs were started and conducted in a rather short time, both putting emphasis on the relatively new technology of fertilizer use. (5) The first program, conducted in the Southern part of the country, extended lab and green house work supplemented by a few field trials to small land owners - the so called "operação tatú" (operation armadillo). (6) The seconde program, covering a larger problem area in the Northeast and in Central Brazil, began directly in field as thousands of demonstrations and simple experiments with the participation of local people whose involvement was essential for the success of the initiative; in this case the official extension services, both foreign and national sources of funds, and universities did participate under the leadership of the Brazilian Association for the Diffusion of Fertilizers (ANDA). (7) It is felt that the Brazilian experience gained thereof could be useful to other countries under similar conditions.
Resumo:
A trial was carried out on an eight old coffee plantation with visible zinc problems. The plantation was situated nearly the city of Jaú (22º30'S, 48º30'W). State of São Paulo, Brazil. The soil is classified as medium texture Oxisol of low base saturation (Latossol Vermelho Amarelo - fase arenosa). The pulverization program started in november 1977, followed in march and July 1978 (heavy harvest) and ended in march and July 1979 (light harvest). Is should be mentioned that a well reconized characteristic of arábica coffe is its habit of biennial bearing, a very heavy harvest is most often followed by a light load the next year. The following treatments and amounts of chemicals per cova hole (4 trees) were tested in accordance with a random block design: 1. 1 g of zinc (zinc sulphate, 0.5%) 2. 3 g of nitrogen (urea, 1.3%) 3. 1 g of zinc + 3 g of nitrogen (zinc sulphate 0.5% + urea 1.3%) 4. 0.25 g, 0.50 g, 1.00 g, 2.00 g of zinc plus 0.75 g, 1.50 g, 3.00 g and 6.00 of nitrogen (correspondent to NZN* 15-0-0-5 as 0.75%, 1-5%, 3.0% and 6.0% by v/v). Foliar absorption data were obtained by collecting the 3rd and 4th pairs of the coffee leaves and analysed them for N, P, K, Ca, Mg, S, B, Cu, Fe, Mn, and Zn. The main results may be summarized as follows: 1. The maximum calculated yields of clean coffee were obtained by the applications of 5.84 1 of NZN (1.13%) per hectare. 2. The applications of zinc sulphate (0.5%) and urea (1.3%) together or separate did not affected the coffee bean production. 3. The applications of 15.0 1 of NZN per hectare reduced the coffee yields. 4. Leaf damages and burning symptoms were observed by the applications of urea (1.3%) plus zinc sulphate (0.5%) and larger doses than 7.5 1 of NZN per hectare. 5. Leaf tissue analysis show that the concentrations of the elements were affecred by the age of the leaves and by the yields of the coffee trees. 6. The applications of increasing doses of NZN causes an increase in the concentration of zinc, manganese and boron in the leaves and decreased the concentration in calcium and potassium the leaves. 7. The concentration of zinc in the leaves associated with the heavy harvest, in July, was 70.0 ppm.
Resumo:
The A. summarises the history of his first culture of acidfast bacillus isolated directly from leprosy lesions (Sample José) and refers about two samples recovered from guinea pig and white rat inoculated with said culture. Then the A. completes his previous descriptions of four cultures of acidfast bacilli isolated by him from ticks (Amblyomma cajaennense and Boophilus microplus, two cultures from each species) infected experimentally in lepers. The A. having found specimens of two species of Triatomidae (Triatoma infestans and Panstrongylus megistus) naturally infected with HANSEN bacillus in huts habited by lepers in the State of Minas Gerais (Dec. 1942), started a series of experiments, using larvae and nymphs of T. infestans bred in laboratory at the Instituto Oswaldo Cruz, to infect in active cases of leprosy, in the city of Rio de Janeiro, could obtain two new samples of cultures of acid-fast bacilli (Ns. 6 and 7 of his set). In this papaer the A. studies the biological properties of said cultures, proving that Penicilin has not effect upon them, like other substances. The sulphuric and acetic acids were used to purify some of the cultures, with good results, the cultures becoming more rich and growing faster. Potassium hydroxide Sodium (10% solution) was also used with success to isolate and to purify the cultures, but it seems that it affects the bacilli in some way. In flud glycerinated media the majority of such cultures produce velum suitable for the preparation of antigens for skin tests and for therapeutical use. At last the A. says that he is becoming convinced that the HANSEN bacillus is in cause, especially after thee evidences of culturing the bacillus from one patient, in different opportunities.
Resumo:
Arrangement of potassium in the tissues having been mentioned, as well as the rôle it plays in some pathological processes such as suprarenal insufficiency, anaphylactic shock and shock caused by hemorrhage or traumatism, experiences were undertaken to establish the rates of plasma potassium during bacteria infections artificially developed in rabbits by K. pneumoniae. P. aeruginosa and S. enteridits. It was concluded that during the period of the infections, the rate of potassium of the plasma increases almost immediately after the inoculation and stays high when the infections are of a serious or mortal character; the rate continue to increase until the death of the animal occurs. When these infections are not very serious, as in the cases of infections resulting from inoculations of bacteria as not recent and consequently with attenuated virulence K pneumoniae, or P aeruginosa and S enteriditis, to which rabbits are naturally very resistant, the rate of potassium of the plasma increases after an intravenous inoculation of germs according to the septicemic period of the infection; however, when, because of its natural resistance, the animal overcomes the infection, the amount of potassium gradually decreases and finally gets back to the normal rate. The action of cortin on potassium of the plasma was also tested on animals suffering from acute infections caused by K. pneumoniae, which, under normal conditions cause death of the rabbits, nor did it increase the rate of potassium of the plasma when a larger amount of bacteria (300,000,000) was inoculated. However, cortin inoculated several times prevented a higher rate of potassium in the plasma during the development of the infection when a smaller number of bacteria (150,000,000) was inoculated, which quantity, under normal conditions, always causes mortal infections. When cortin is discontinued 20 hours after the inoculation of germs, the infection increases fastly and the animal dies in a very short time. Now, if the injections of cortin continue to be given every hour until the 26th hour instead of only until the 20th hour, the amount of potassium in the plasma very high if the hormones substance is no longer inoculated gradually becomes smaller and finally comes back to the normal rate if the inoculations continue to be made; it will increase again only if the substance is no longer injected; after a few hours the injection is gone, potassium is found to come back to its former rate, and in consequence the animal is perfectly cured of an infection otherwise mortal. ln view of the results thus obtained, it was concluded that, during the development of those infections, the checking of the rate of potassium of the plasma provided a means of controlling the resistance of a body suffering from an infection, that rate increasing when the infection is developing and becoming more severe, or getting back to normal when the infection decreases. The checking of the rate of potassium of the plasma also made known the action of cortin on the tissues, which is found to control the permeability of the cells to potassium. Suggestions were made that potassium of the plasma be thereofre checked during infections in the human body, to make possible proving that the phenomena studied in those animals also take place in the human body. In case this is found to be true, we sould possess an important element to check organic vitality during infections.
Resumo:
Studies have been carried out on the method of Britton and Silvette modified by Reinecke and Kendall, for the evaluation of cortico-adrenal extracts, based on the deposition of glycogen in the liver of adrenaletomized rats. The test was performed in a total of 180 normal and adrenalectomized rats. The extracts tested were: a) an aqueous extract of cortico-adrenal cortex prepared by the Swingle and Pfiffner technique; b) the same extract added with ascorbic acid (Supracortin Labor); c) desoxycorticosterone acetate (Percortol Ciba and Syncortyl Roussell). Male rats were used, ranging from 40-200g, fed since the 18 th days old with a special diet, in which they were maintained until the day before the injection. Adrenalectomy was performed under urethane anesthesia. The fourth day after operation, food was removed and they were fasted for 24 hours. In the morning of the fifth day, injections of the material to be assayed were given at hourly and two hours intervals, during four to eight hours. One or two hours after the last injection, the animals were sacrified, the livers removed and dropped into a hot 30% solution of potassium hydroxide, and worked by Good, Kramer and Somogyi method. The glycogen was calculated as milligrams per lOOg of body and liver weight. The results obtained are shown in the tables I, II, and III. When several dosages of the same sample of extract were made (5 animals each dose), the amount of glycogen deposited in the liver per lOOg of body and liver weight, was found to be a positive function of the dose injected. The graph 2, shows these results. The synthetic compounds were ineffective. Our results are in agreement with those of Reinecke and Kendall and of Olson et al.
Resumo:
The engineers of the modern University City are constructing a graceful bridge, named PONTE OSWALDO CRUZ, that crosses a portion of the Guanabara Bay (Fig. 1). The work at west pillar stopped for 3 years (The concret structure in Est. 1). As it will be seen from n.º 1 5 of the fig. 1, Est. I, the base of the structure will have five underground boxes of reinforcement, but, to-day they are just like as five uncovered water ponds, until at present: May 1963. (Est. I fig. 3, n.º 3 pond n.º 3; A. old level of the water; B. actual level of the water; c. green water; E. mass of bloom of blue algae Microcystis aeruginosa). Soon after SW portion, as 5 cells in series, of the pillar abutments, and also the NE portion nearly opposite in the Tibau Mount will be filled up with earth, a new way will link Rio City and the University City. We see to day Est. I, fig. 1 the grasses on the half arenous beach of the Tibau Point. These natural Cyperaceae and Gramineae will be desappear because of so a new road, now under construction, when completed will be 33 feet above the mean sea level, as high as the pillar, covering exactly as that place. Although rainfall was the chief source of water for these ponds, the first water (before meterorological precipitations of whatever first rain it might fall) was a common tap water mixed with Portland Cement, which exuded gradually through the pores of the concret during its hardenning process. Some data of its first cement water composition are on the chemical table, and in Tab. n.º 4 and "Resultado n.º 1". The rain receiving surface of each pond were about 15 by 16 feet, that is, 240 square feet; when they were full of water, their depth was of 2 feet 3", having each pond about 4,000 gallons. Climatic conditions are obviously similar of those of the Rio de Janeiro City: records of temperature, of precipitation and evaporation are seen on the graphics, figs. 2, 3, 4. Our conceptions of 4 phases is merely to satisfy an easy explanation thus the first phase that of exudation of concrete. We consider the 2nd. phase formation of bacterian and cyanophycean thin pellicel. 3rd. phase - dilution by rains, and fertilisation by birds; the 4th phase - plankton flora and fauna established. The biological material arrived with the air, the rains, and also with contaminations by dusts; with big portion of sand, of earth, and leaves of trees resulted of the SW wind actions in the storming days (See - Est. I, fig. 3, G. - the mangrove trees of the Pinheiro Island). Many birds set down and rest upon the pillar structure, its faeces which are good fertilizers fall into the ponds. Some birds were commonly pigeons, black ravens, swallows, sparrows and other sea mews, moor hens, and a few sea birds of comparatively rare occurence. We get only some examples of tropical dust contaminated helioplankton, of which incipient observations were been done sparcely. See the systematic list of the species of plankters. Phytoplankters - Cyanophyta algae as a basic part for food of zooplankters, represented chiefly by rotiferse, water-fleas Moinodaphnia and other Crustacea: Ostracoda Copepoda and Insecta: Chironomidae and Culicidae larvae. The polysaprobic of septic irruptions have not been done only by heating in summer, and, a good reason of that, for example: when the fifth pond was in polysaprobic phase as the same time an alike septic phase do not happened into the 3rd. pond, therefore, both were in the same conditions of temperature, but with unlike contaminations. Among the most important aquatic organisms used as indicatiors of pollution - and microorganisms of real importance in the field of sanitary science, by authorities of renown, for instance: PALMER, PRESCOTT, INGRAM, LIEBMANN, we choose following microalgae: a) The cosmopolite algae Scenedesmus quadricuada, a common indicator in mesosaprobio waters, which lives between pH 7,0 and it is assimilative of NO[3 subscripted] and NH[4 subscripted]. b) Species of the genus Chlamydomonas; it is even possible that all the species of theses genus inhabit strong-mesosaprobic to polysaprobic waters when in massive blooms. c) Several species of Euglenaceae in fast growing number, at the same time of the protozoa Amoebidae, Vorticellidae and simultaneous with deposition of the decaying cells of the blue algae Anacystis cyanea (= Microcystis) when the consumed oxygen by organic matter resulted in 40 mg. L. But, we found, among various Euglenacea the cosmopolite species (Euglena viridis, a well known polysaprobic indicatior of which presence occur in septic zone. d) Analcystis cyanea (= M. aeruginosa) as we observed was in blooms increasing to the order of billions of cells per litter, its maximum in the summer. Temperatures 73ºF to 82ºF but even 90ºF, the pH higher than 8. When these blue algae was joined to the rotifer Brachionus calyflorus the waters gets a milky appearance, but greenished one. In fact, that cosmopolite algae is used as a mesosaprobic indicator. Into the water of the ponds its predominance finished when the septic polysaprobic conditions began. e) Ankistrodesmus falcatus was present in the 5th pond from 26the. April untill the 26th July, and when N.NH[4 subscripted] gets 1.28 mg. L. and when chlorinity stayed from 0.034 to 0.061 mg. L. It never was found at N.NH[4 subscripted] higher than 1 mg. L. The green algae A. falcatus, an indicatior of pollution, lives in moderate mesosaprobic waters. f) As everyone knows, the rotifer eggs may be widely dispersed by wind. The rotifer Asplanchna brightwelli in our observation seemed like a green colored bag, overcharged by green cells and detritus, specially into its spacious stomach, which ends blindly (the intestine, cloaca, being absent). The stock of Asplanchna in the ponds, during the construction of the bridge "PONTE OSWALDO CRUZ" inhabits alkaline waters, pH 8,0 a 8,3, and when we observed we noted its dissolved oxygen from 3.5 to 4 mg. L. In these ponds Asplanchna lived in 0,2 P.PO[4 subscripted]. (Remember the hydobiological observations foreign to braslian waters refer only from 0.06 to 0,010 mg. L. P.PO[4 subscripted]; and they refer resistance to 0.8 N.NH[4 subscripted]). By our data, that rotiger resist commonly to 1.2 until 1.8 mg. L.N.NH[4 subscripted]; here in our ponds and, when NO[2 subscripted] appears Asplanchna desappears. It may be that Asplanchna were devoured by nitrite resistant animals of by Culicidae or other mosquitoes devoured by Due to these facts the number and the distribution of Asplanchna varies considerabley; see - plates of plankton successions. g) Brachionus one of the commonest members of class Rotatoria was frquently found in abundance into the ponds, and we notice an important biological change produce by the rotifer Brachonus colyciflorus: the occurence of its Brachionus clayciflorus forms pallas, is rare in Brazil, as we know about this. h) When we found the water flea MOinodaphnia we do not record simultanous presence of the blue algae Agmenellun (= Merismopedia).