RCAAP Repository

An experiment was conducted in glass-house in order to check the effects of different levels of calcium on the micronutrient composition of millet plants during 38 days. The following treatments were applied: 0, 50, 100, 150, 200, 250 and 300 ppm of calcium in the nutrient solutions. The plants were harvested after 38 days and divided into young leaves, old leaves, ears and stolk, which were analyzed for B, Cu, Fe, Mn and Zn. The authors concluded: The calcium levels reduced the concentrations of Zn, Cu, Fe, Mn in the plants; The calcium levels did not affected the absorption of B; The calcium levels in the nutrient solutions did not affected the minimum requirements of Cu, Fe, Mn and Zn for the cattle nutrition.

In a pot experiment, samples of 17 São Paulo State soils, were fertilized with 0 and 400 kg of total P(2)0(5) /ha by the addition of Araxa apatite and triple superphosphate. Rice was grown and the aerial part was cut after 40 days and used as a biological index. The dry matter weight was correlated to soil available P, determined by H2SO4 and by ionic exchange resins. It was not possible to determine which soils properties influenced the apatite solubilization, but seems that pH and native soil P, can indicate some aspects of the process.

Cerely (Apium graveolens L. var. dulce) is not very much cultivated in Brazil, but nowadays its cultivation has been expanded because of the increasing use of it mainly by desidrated soup industries. As the countries that tradicionally cultivate cerely have present serious nutricional problems, this work was proposed with the next objectives: To examine the effects of increasing doses of calcium in the development and production. To describe the symptoms of calcium deficiency and of excess of calcium supply. To verify the differences in resistance to the blackkeart anomaly between the cultivars Cornell 6-19 and Golden Detroit. To affair these objectives a green houve experiment was carried out us which cerely plant were cultivated in nutrient solutions which had the following calcium concentrations: 0, 50, 100, 150, 200 and 300 ppm of calcium. The authors concluded: It is possible to characterize a deficiency of calcium in both cultivars. The cultivar Golden Detroit presents a greater resistance to the symptoms of calcium deficiency. The increasing of the calcium concentration in the nutrient solutions induce a decrease of Mn concentration at the plants.

Three experiments were conducted under controlled conditions with the objectives of evaluating the effect of different concentrations of phosphorus and on the presence of other ions on the kinetic of absorption. Excised roots of rice and bean were placed in aereated solutions containing increasing concentrations of NaH2PO4 (10-7 M to 5x10-2M) during 90 minutes. The rate of absorption (v = mmols P/g dry matter) and the kinetic constants Vmax and Km were determined. Similar procedure was used to to evaluate the interaction of Mg+2, Al+3, K+, N-NH4+, N-NO3- and N-ureia in the uptake of phosphorus during 120 minutes. In another experiment, the effect of the presence of Mg+2 and/for Al+3 in the uptake and redistribution of phosphorus, was evaluated by varying the external concentration (1 ppm, 5 ppm, 10 ppm and 20 ppm) during a period of 17 hours, and utilizing whole rice plants. It was observed a dual mechanism, with two phases following the Michaelis-Menten kinetics and with transition phase 1 - 50 x 10-5 M. The best explanation of the experimental data was obtained, by transforming the data in accordance with HOFSTEE (1952). Bean was more efficient than rice in the first phase of uptake (higher Vmax). Al+3 had a clear stimulatory effect on the uptake of phosphorus, promoting, however, the anion fixation in the root at lower concentrations. At the highest concentrations (20 ppm) of phosphorus this effect was not evident. No effect on the uptake was observed with Mg+2, K+ and different forms of nitrogen. Urea could have a depressive effect although, not significant. Possible mechanisms invelved are discussed.

An experimental trial was carried out to determine the dry matter production ot wheats plants submetted to two level of water availability the cultivates used were: BH 1146 recomended for non irrigated areas and IAC-24 Tucuruí recomended for medium flooded areas. The experimental trial was carried out on a Latossolo Roxo (Eutrustox) and was fertilized with 20 kg of N and 90 kg of P2O5 per hectare. The plants were cuted and dried at the following stages: 10 days, at the begining of fillering; 30 days, at the stem alongation; 50 days at the joiting; 70 days, ate the flowering; 90 days, at the begining of grain formation and 110 days at the maturity of the grains. The authors concluded: The irrigation increased the dry matter production in both cultivates in all ages; Under dry land the cultivate IAC-24 Tucuruí showed the highest dry matter profuction; Under irrigation the cultivate IAC-24 Tucuruí showed the highest dry matter production.

The analysis of areas with different slope classes (A = 0-3%, B = 3-8%, C = 8-16% and D = 16-30%) is made with the purpose of verifying the TM/LANDSAT images potentiality in agricultural planning. Due to the absence of tridimensional viewing, the work is based on quantitative relations between drainage indices (river frequency and drainage density) determined on the images, and the relief expression (average slope) extracted from planialtimetric topographic charts (1: 50,000 scale). Aerial photographs on a 1:35,000 escale are utilized for comparisons. The main conclusion is that the utilization of TM/LANDSAT images in mapping slope classes through drainage network is feasible, though the characteristics of the analysed region caused an easier differentiation between areas of the A and B classes and those of the C and D classes.

Results of laboratory trials showed a negative effect of the age of adults of Trichogramma demoraesi on the parasitism of eggs of Anagasta kuehniella and on the lenght of the immature stage of the parasitoid. These parameters were constant for insects 2 to 6-day-old and decreased significantly after the sixth day. The highest parasitism rates and immature stage lenght, for insects fed or not with a 50% honey solution, were obtained with 4 to 6-day-old adults and the parasitism did not occur with 10-day-old adults. Males of A. kuehniella kept together with females in the cages increased the fecundity of the moths by 938.75% when they were kept without food and by 393-95% when they were fed with honey diet. The females longevity did not vary in function of the diet and it was slightly less in the females than in the males. When eggs of A. kuehniella containning the parasitoid in the pupal stage were stored at 5°C, there was no effect on the emergence of the parasitoid until 7 days of storing, with a small though continuous reduction on the emergence after this period of storing.

The presente work done in order to study the behavior of a group of cultivars of bush snap beans and the influence of population density on yield. The cultivars used were: 'Contender', 'Tendercrop', 'Gallatin 50', 'Early Gallatin', 'Harvester' and 'Eagle'. The best cultivars were: 'Contender', 'Early Gallatin' and 'Tendercrop'. It was remarkable the earliness of 'Contender'. As the density increased the number of pods per plant decreased progressively, but the yield of pods increased. The highest yields were observed at 28 plants/m².

No summary/description provided

No summary/description provided

A private farm was used to study the postpartum ovarian activity in dairy cows in São Paulo State. Milk samples were collected from 26 animals, twice weekly for one year to monitor the progesterone profile using the radioimmunoassay in detecting the first oestrus in postpartum. The percentage incidence of cows with detectable ovarian activity was 61.1% for animals 31 to 60 days postpartum.

In order to evaluate the performance of several chemicals to control the citrus leprosis mite on orange-trees a test was performed in Rio das Pedras, State of São Paulo, Brazil. The treatments were as follows: A) control; B) fenpropathrin, 13.5g; C) clofentezine, 20.0g; D) biphenthrin, 5.6g: E) binapacryl, 50.0g; F) flubenzimine 60,0g; G) ciexathin, 20.0g. The amounts above are in active ingredients per 100 liters of water. Each orange-tree received 4.0 liters of liquid (1332 liters/hectare). Seven evaluations of the mite infestation were made on fruits: the first, one day before and 02, 15, 30, 44, 65 and 79 days after spray. The best results were obtained in the treatments with ciexathin, binapacryl and biphenthrin.

In order to evaluate the performance of some pesticides to control the two-spotted spider mite T. urticae, a test was performed in Americana, State of São Paulo, Brazil. The seven treatments were as follows: A) control; B) hexythiazox, 50g: C) hexythiazox, l00g; D) clofentezine, 150g; E) clofentezine, 250g; F) thuringiensin, 255g; G) clofentezine plus multimethyl alquenol (150g + 5.28g). Quantities above mentioned are of active ingredients per hectare (Table 1). Two days after the application, the best treatment was thuringiensin; after 08 days all treatments differed from the control and 15 days after the spray there was no significative difference among the treatments (Table 3).

In order to evaluate the action of five insecticides against the termite Cornitermes cumulans (Kollar, 1832) (Isoptera, Termitidae) a test was performed in Piracicaba, State of São Paulo, Brazil. The treatments were as follows: A) thuringiensin, 1.2g; B) fenpropathrin, 0.6g; C) abamectin, 0.lg; D) fenthion, l.0g; E) profenophos, 1.5g. The mentioned quantities are of active ingredient per nest. Fifty termite mounds were measured and divided in 5 groups. A vertical channel was made from the top to the center (nucleus) in each mound with a 60cm long steel bar. All the liquids were applied into the nests (1.0 liter of water plus insecticide). About six months later nests were destroyed. The mortalities evaluated for the different treatments were: A) 55.5%; B) 70.0%; C) 90.0%; D) 100.0%; and E) 62.5%. Treatments A and D had 9 nests each and E, only 8 (Table 2).

In the present study, a comparison was made between the multiple-weighing method, in which a 500ml Erlenmeyer flask and a 0.lg precision balance are utilized, and the usual oven-drying method, considered an universal comparator for being the most accurate, in which the soil sample is placed to dry in an oven at 105-110°C for a period of 18-24 hours. In order to test the methods under study, samples of three different soils were utilized: Luiz de Queiroz Series, Sertãozinho Series and Monte Olimpo Series. The data obtained were analysed statistically and evidence was shown that a high correlation exists between the methods, with indices of 0.9719, 0.9458 and 0.9487, respectively.

The purpose of this paper is to verifythe influence of a rural edification orientation on the radiant thermal load (solar radiation) intercepted byit. The authors examined two situations commonlyfound: the North-South and East-West orientations. In order to determine the radiant thermal load, so important in the ventilation and refrigeration problems, it was assumed a model of construction as an example and the proposed relations can be applied to anydesired construction model. The results show that the radiant thermal load from East-West reached 74% of the North-South exposure.

Populational dynamics and effects of rainfall, maximum, minimum and average temperature on the movimentation of adults of A. variegatus, A. sexmaculatus were determined in Maria da Fé-MG, Brazil, during 1986. These species, mainly the first one, have become important as agricultural pests due to the damage caused by their larvae on seeds before germination. Since they were very attracted by the bright yellow collor Moericke traps were used for monitoring adult populations. The first insects were trapped on late January or early february and the populations increased very fast. Because they are polenofagous the infestation could be related to the flowering of corn planted in this place in rotation with potatoes. A small populational peak was observed in the first week of march and the acme occurred about seven days later when 886 adults of A. variegatus and 240 A. sexmaculatus were captured per trap during one week. Then the populations decreased and no more adults were observed after june. The study of Linear Multiple Regression between the climatic factors and the number of insects trapped showed that the maximum temperature was the variable more related to the movimentation of adults of both studied species.

The objetive of the study is to analyse the relationships that the public officer (agronomist, teacher, social worker, etc.) establishes during the process of rational intervention in the socio-economic reality (process that is called socio-economic planning). It shows the position of this public officer as a social change agent or as social conservation agent, his knowledge about the reality, the options and the values used to orient the intervention.

This study was carried out in order to evaluate the yield of ten clones of rubber tree (Hevea spp) in the State of São Paulo, Brazil. The yield data were collected during 16 years from trees cultivated in a Coastal Region at the Experimental Station "Vale do Ribeira" (Pariquera-Açu) and during 17 years in high plain at Experimental Center "Theodureto de Camargo"(Campinas).Comparing annual average yield by Tukey test it was found that the most productive clones are RRIM 600 and BSA 20. The first is cultivated at the Experimental Station and the other at the Experimental Center. Following the best ones, there is an intermediate group formed by clones Ga 1328, Tjir 16, C 228, RRIM 526, C 297, LCB 510 and Fx 25, all of them planted at the Experimental Center. Clones Fx 25, C 290 and RRIM 600 cultivated at the Experimental Center are among the least productives. The Fx 25 clone showed low yield in both regions, although its yield was higher at the Experimental Station than at the Experimental Center. The same was found for the clone RRIM 600.

With the purpose of studying the possible allelopathy characteristics of the common kale (Brassica oleracea L. var. acephala DC.), an experiment was conducted in laboratory conditions, at E.S.A. "Luiz de Queiroz", in Piracicaba, São Paulo State. Tomato seeds (Lycopersicon esculentum Mill. cv. Santa Cruz) were put to germinate in solutions with different concentrations (0; 25; 50 and 100%) of the extract obtained from the air part (leaves) of the common kale. Effects pronouncedly inhibitories of the germination of the tomato seeds were found in the largest concentrations of the common kale extract. The seedlings which germinated in the parcels treated with the extract presented reduced growth morpfo-physiologically abnormal and with larger time for the beginning of the germination. All these characteristics were more pronounced in the parcels with larger concentrations of the extract.