RCAAP Repository

Nesta nota são apresentados os resultados de um estudo relativo aos efeitos das coberturas vegetais de Pinus elliottii com 9, 14 e 19 anos de idade, de Pinus taeda, com 19 anos, de Piniuspatula com 19 anos, e de vegetação natural de um solo de cerrado do município de Assis, Estado de São Paulo, sobre os teores de argila, dispersa em água e em calgon, limo, areia total, areia grossa, areia média, areia fina e areia muito fina. 0 estudo se refere às camadas de 0-30 cm e de 30-60 cm de profundidade. Conclui-se que: a) Na área com cobertura natural de cerrado houve um acúmulo de argila, dispersa em água e em calgon, na camada de 30-60 cm e uma redução no teor de areia total nessa mesma camada em relação à camada de 0-30cm; b) Na área coberta com Pinus elliottii de 14anos de idade, houve um acúmulo de limo na camada de 0-30 cm e de areia fina na camada de 30-60 cm. Não houve outros efeitos das coberturas vegetais sobre a diferenciação dos teores dos constituintes granulométricos em observação entre as camadas de 0-30 cm e de 30-60 cm de profundidade.

This research deals with the effects of exogenous growth regulators on germination of seeds of several plants. To study the influence of the chemicals, Zea mays, Crotalaria juncea, Lablab purpurcus, Arachis hypogeae, Setaria anceps, Brachiaria humidicola. Stylosanthes sp . , Macroptilium a tropurpurcum , Tefrosia candida, Neonotonia wightti and Panicum maximum seeds were immersed during 22 hours in water solutions of (2-chloroethyl ) trimethylammonium chloride (CCC) 2000 ppm, succinic acid - 2,2-dimethylhydrazide (SADH) 4000 ppm, gibberellic acid (GA) 100 ppm, indoIylacetic acid (IAA) 100 ppm, 6-furfurylaminopurine (FAP) 100 ppm, and water ascheck treatment. GA increased germination of Brachiaria, Macroptilium, Neonotonia and green panic. GA also promoted a more rapid growth of Crotalaria, Lablab and Stylosanthes seedlings. IAA application increased growth of Stylosanthes seedlings; GA and IAA also increased the leaf number of these plants. Soaking Lablab and peanut seeds in SADH reduced the growth of the seedlings. FAP treatment reduced the growth of corn and Lablab plants and increased the growth of Stylosanthes.

In an experiment carried out in Jundiaí, São Paulo State, it was studied the possibility of termination of rest in plant buds by treatment with chemicals. The control of bud sprouting in the vineyard is important to pre vent chilling effects and to increase grape harvesting period. At October, 28, two hours after pruning, 'Niagara Rosada' plants were treated with calcium cyanamide at 20% applied on buds and on cuted region of pruned twig, sprayed with Alzodef 2% and 5%. It was observed that Alzodef 2% terminated bud rest more rapidly in relation to the control plants. Application of calcium cyanamide 20% on buds or on cuted region, and spraying with Alzodef 2% or 5% promoted good results on terminate bud rest of 'Niagara Rosada' plants. The chemiacals did not affect significantly the quantity of bunches and the yield per plant.

The appearance of the so called "bull-whip" in the leaves of millet plants in the field was recognized as a calcium deficiency symptom. The authors collected soil and leaves samples and run analysis for Ca, Mg and K content. The results showed a high content for Ca, Mg and K in the soil and low content of Ca in the leaves. During the final stage of the plantation a very intensive raining period occured. The authors concluded that the calcium deficiency was induced by the excess rain and low transpiration rate of the plants.

With the purpose of determining the most adequate levels of nitrogen, phosphorus and potassium for the production of plants ready for grafting in nursery, a trial was carried out in a sandy clay loamy yellow Latosol in Mosqueiro Island-PA, Brazil. It was used a randomized block design with two replications following a factorial design of 33. The levels applied were of 0-2.1-4.2 g/plant of N; 0-3-5-7-0 g/plant of P2O5; 0-1.4-2.8 g/plant of K2O and a permanent level of 0.8 g/plant of MgO, the sources applied were, respectively, ammonium sulfate, triple superphosphate, potassium chloride and magnesium sulfate. The results were abtained two-hundred and twenty days after the beginning of the trial, the following evaluations were made: chemical analysis of soil and leaves, plants height, stem diameter, dry matter weight of aerial parts and plant ready for grafting. Based on the overall results od the study it was concluded that the adequate levels were 330 kg/ha (4.6 g/plant) of N; 340 kg/ha (4.8 g/plant) of P2O5 and 190 kg/ha (2.7 g/plant) of K(2)0, together with the permanent level of 60 kg/ha (0.8 g/plant) of MgO, producing a rate of profit of eighty-seven percent of plant ready for grafting.

The following treatmente were employed: complete, without nitrogen, without phosphorus, without potassium, without calcium, without magnesium, and without sulphur. Washed sand was used as a substrate, being the plants watered twice a day with the correponding nutrientsolution. After the deficiency symptoms establishment, the plants were cut and separated in upper needles, lower nedies, branches and roots, dried at 75 ºC and weighed. Seedlings dry matter productions are depressed by omission of N, P and S for P. caribea var. hondurensis,by omission of N and S for P. caribae var. caribaea and by omission of N for Pcaribae var. bahamensis, being upper needles' and branches' dry matter productions the major depression sources. P. caribaea seedlings dry matter productions aren't significantly affected by low levels of K, Ca and Mg in nutritive solution.

Este trabalho tem o objetivo de dar continuidade às pesquisas que visam o combate ao ácaro rajado do algodoeiro Tetranychus urticae. Koch, 1836. Para tal objetivo, em oito tratamentos foram utilizados seis produtos:fempropatrina(300 g/ha), binapacril (400g/ha) , flubenzimina (600g/ha) , carbamato UC 81341 (150 g IA/ha), clofentezina em dois tratamentos (150 g/ha repetidas em três aplicações e 375 g/ha) e bifentrina (70g/ha). A conclusão, extraída da análise dos resultados, permite verificar que os seguintes tratamentos agiram consideravel mente sobre a população do àcaro: ciofentezina em três aplicações e bifentrina. No final do ensaio, procedeu-se à avaliação dos danos ocasionados pelo bicudo do algodoeiro Anthonomus grandis grandis às maçãs. A infestação foi semelhante em todos os tratamentos.

This test was carried out in Santa Bárbara D'Oeste, State of São Paulo, Brazil. The treatments and quantities of active ingredients per hectare were: A - check (no pesticide); B -biphenthrin, 70 g; C - carbamate UC 81341 , 150 g; D -biphenthrin, 50 g; E - carbamate UC 81341, 100 g; F-bromopropilate, 500 g; - clofentezine, 500g. Endosulfan was added to each experimental pesticide in order to control the cotton boll weevil Anthonomus grandis grandis Boh. In the first avaluations the best control was obtained with biphenthrin. In the last avaluations, clofentezine was the best.

This test was carried out in Santa Bárbara D' Oeste, State of São Paulo, Brazil, to evaluate the action of seven pesticides against the two-spotted spider mite. The treatments were eight with four repetitions. Each treatment utilized 800 m² and had the following characteristics: A - check; B - clofentezine, 250 g; C - f enpropathr in, 150 g; D - binapacryl, 800 g; E cypermethrin plus profenofos, 50 g plus 500 g; F clofentezi ne, 750 g; G - clofentezine , 250 g; H - fenpropathrin, 75 g. The quantities of pesticides above were of active ingredient per hectare. Except in the treatment B, where two applications of clofentezine was performed, all other treatments received only one spray. Endosulfan was added to the experimental pesticides in order to control the cotton boll weevil. The best results were obtained in the treatments that employed clofentezine (treatments B, F and G).

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O presente trabalho é uma revisão histórica sucinta da atuação de fitopatologistas, fitovirologistas e outros técnicos no Brasil na área das viroses de plantas. É considerado que a estrutura atual da pesquisa fitovirológica existente a nível federal ou estadual no país é suficiente para enfrentar problemas representados pelas viroses de nossas culturas. Mas é apontado que há falta de uns poucos centros de pesquisa básica com vírus de plantas independentemente de considerações econômicas de problemas existentes. É mencionado que há dificuldade. em obter recursos para qualquer instituição ou grupo que trabalhe em pesquisas mais básicas e que essas são melhor adaptadas a uma universidade ou instituto altamente especializado.

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A pot experiment was conducted in a green house in Piracicaba, Brazil, in order to determine, the effects of omission in growth, the corresponding internal levels and the efficiency of macronutrients use for young plants of P. oaribaea var. hondurensis, P. oaribaea var. bahamensis and P. caribaea var. caribaea. The following treatments were employed: complete, without nitrogen, without phosphorus, without potassium, without calcium, without magnesium, and without sulphur. Washed sand was used as a substrate, being the plants watered twice a day with the corresponding nutrient solution. After the deficiency symptoms establishment, the plants were cut and separated in upper needles, lower nedles, branches and roots, dried at 60-70°C, weighed, ground and analysed for N, P, K, Ca, Mg and S concentrations . The internal levels in needles under complete and deficient treatments are: N% 1.33 and 0.54, P% 0.03 and 0.02, K% 1.76 and 0.34, Ca% 0.23 and 0.04, Mg% 0.22 and 0.04, S% 0.24 and P0.09 for P. caribaea var. hondurensis; N% 1.30 and 0.51, P% 0.02 and 0.02, K% 1.51 and 0.35, Ca% 0.14 and 0.05, Mg% 0.15 and 0.08, S% 0.16 and 0.06 for P. caribaea var. bahamensis and; N% 1.18 and 0.43, P% 0.01 and 0.02, K% 1.51 and 0.34, Ca% 0.15 and 0,04, Mg% 0,13 and 0.08, S% 0.11 and 0.06 for P. caribaea var. caribaea. P. caribaea var. hondurensis is less effective in macronutrient absorption.

In order to contribute to the knowledge of the floral biology of Chrysophyllum auratum Miq. (SAPOTACEAE) two cultivated specimens was analised in Horticulture Section of Escola Superior de Agricultura "Luiz de Queiroz", Piracicaba - SP. The survey included floral phenology and the establishment of reproductive systern. The flowers had vespertine andnocturnal anthesis and protandrie. One spicemen exhibited a phenological precocity. The pollination syndrome was miofily but no biological pollinator agents was observed. No conclusion about the reproductive system were possible with the tests.

An experiment was carried out under field conditions to determine: - the growth of muskmelon (Cucumis melo L.) throght accumulation of dry matter; - concentration and consequent accumulation of nutrients in the aereal parts of the plant at different growth stages; - exportation of nutrients at fruit harvesting, at the time of consumption. The experiment consisted of sampling at five growth stages - 15, 30, 45, 60 and 70 days after emergence - of competitive plants, which were cut at ground level, divided into stem and branches, leaves, flowers and fruits, to determine the quantity of dry matter and for chemical analysis of mineral macronutrients. The treatments, represented by sampling time, consisted of randomized block design with four replications. It was concluded that: - the growth was slow at the deginning, increasing later, especially between 30 and 45 days; - at the end of the cycle, the plant accumulated 905,88 g dry matter as follow: stem and branches - 18,38%, leaves - 30.32%, and flowers and fruits - 50.30%; - the concentration of nutrients in the aereal parts varied according to the age and part considered; - there was a tendency for reduction in the concentration of macronutrients, except for sulphur; - at 75 days, the aereal part accumulated, in milligrams per plant: 23.08 N, 3.46 P, 28.90 K, 12.74 Ca, 5.55 Mg, 1.595 S; - in a one-ton harvest the fruits exported about 1.78 kg N, 0.33 kg P, 2.64 kg K, 0.14 kg Ca, 0.21 kg Mg, 0.09 kg S.

It is quite common in brazilian rubber plantations the occurence of boron deficiency symptoms on the leaves associated with N, P, K, Mg fertilizer programs. A simple experiment involving the daily aplication of five levels of boron (0.5, 1.0, 1.5, 2.0, 2.5 ppm) to established rubber seedlings was carried out in a greenhouse with washed sand to determine the effects of excess boron associated with toxicity symptoms. The symptoms were observed nine days after commecement of treatments. The concentration of boron in the leaves were from 316 to 1300 ppm. In the stem and roots the concentrations of boron were lower from 21 to 81 ppm of boron on dry matter. Tip and marginal necrosis of the leaf occured when the boron concentration in the substract were 1.0 to 2.5 ppm of boron. The rubber plants exhibet early defoliation. The authors concluded that a very carefull atention should be taken when the application of boron under field condition in rubber plantations .