RCAAP Repository

Thornthwaite and Blaney-Criddle's methods were used to estimate the evapotranspiration rate in a potato field-crop under three soil moisture regimes. The evapotranspiration data obtained by the soil-water balance method were well correlated with those obtained by the two empirical methods, manly from the stage of tuber growth to maturity. Blaney-Criddle's consumptive use factors supplied the higher correlation coefficient and presented monthly consumptive use coefficients very approximate to those observed in another sites, whereas Thornthwaite's formula markedly underestimated the measured values during all lenght of the growing season. This fact could not be justified by the thermal lag. The lack of precision of the estimates observed in the present field-test seems to involve the parameters and constants of the Thornthwaite's formula. At plant emergence and in the first phase of stolon formation, the correlation coefficients were lower than for the other stages, mainly when Thornthwaite's formula was used.

From a grove of E. citriodora (20 years) and P. taeda (24 years) site on a red-yellow podzolic (ultisol), at Piracicaba (22° 43' S, 47° 38' W, elev. 1933 ft., av. annual precipt 1,170 mm), SP, Brazil, leaves, litter fall an soil samples (0 - 10 and 10 - 20 cm depth) were collected. Chemical analysis were run for macro and micronutrients, except for Cl and Mo, by conventional modes. The authors concluded: 1. The E. citriodora was better supplied in nutrients than P. taeda, except for iron; 2. Both forest species hence the organic carbon content in the soil; 3. E. citriodora improved the potassium and magnesium contents in the soil. 4. P. taeda improved the available aluminium of the soil; 5. Both forest species henced the potassium content the litter fall; 6. The fall was improved in iron by P. taeda.

The present work was carried out in order to study: 1. The symptoms of deficiency of macro and micronutrients; 2. The modification induced by those treatments in the histological make up of the leaves; 3. The effect of the deficiency on the chemical composition of leaves (+1, +2, +3), (+4, +5, +6), (+7, +8, +9) and sheats (+4, +5, +6). Young sugar cane plants were grown in nutrient solution, two treatments being used: complete solution (HOAGLAND & ARNON, 1950), deficient solution, in which a given nutrient were omited. Symptoms of malnutrition were observed in all treatments. The deficiencies affected the characteristic of the chloroplast observed through the histological examinations. Non deficient and deficient levels for the macronutrientes in the leaves expressed in function of the dry matter were.

Plant production is a result of manu integrate physiological processes which occur during growing season. Whathever those processes show considerable individuality with relation to environment. In this work the vegetative growth of potato plants (Solanum tuberosum L.) growing in the field was observed for three soil moisture regimes in three growth stages. The vegetative growth was evaluated through leaf area estimate in weakly basis. The results showed that by the ending of the first growth stage (about 25 days after plant emergency) the vegetative growth in the treatment where soil water matric potential never dropped less than -0.5 bar, exceeded in about 34 percent that observed for plants submitted to moderate water deficits (-1.0 bar), and in about 80 percent for those submitted to more severe water deficits (5.0 bars). However, the inhibition of vegetative growth in the first treatment was partially recovered after the re-establishment of suitable soil water condition. Occuring more severe water deficits in the initial growth stage, recovering of normal rates of vegetative growth did not occur upon rewatering. Intensive soil water depletion after complete vegetative growth hastenned plant senescence when compared with plants growing in well watered soils.

This paper has is view the joint analysis of augmented trials in randomized blocks. Each experiment had t = c + z, in r blocks where we have c commom treatments, that is, treatments present in each blocks, and z regular treatments, which appear in only one of the r blocks. Each block has k = c + pj plots, where pj (j = l, ..., r) is the number of regular treatments in it. The analysis was carried out, taking the whole set of trials as one experiment with incomplete blocks, assuming that the trials had similar variances. In the example presented, treatments belonged to six classes of association, with least significant difference (by Tukey's method) between two of them (Δ) given below: 1. Two common treatments: Δ 1% = 15.955 t/ha; Δ 5% = 13.755 t/ha. 2. A common treatment and a regular one: Δ 5% from 23.047 to 23.216 t/ha; Δ 1% from 26.733 to 26.930 t/ha. 3. Two regular treatments, with λ = 3: Δ 5% from 28.515 to 28.659 t/ha; Δ 1% from 33.075 to 33.243 t/ha. 4. Two regular treatments, with λ = 2: Δ 5% from 29.064 to 29.950 t/ha; Δ 1% from 33.711 to 34.739 t/ha. 5. Two regular treatments, with λ = 1: Δ 5% from 29.160 to 29.994 t/ha; Δ 1% from 33.823 to 34.791 t/ha. 6. Two regular treatments, with λ = 0: Δ 5% from 30.281 to 30.628 t/ha; Δ 1% from 35.124 to 35.526 t/ha. We realize, therefore, that these leat significant differences are rather smaller in the case of two common treatments, but are not too different in the other cases.

This paper object is to show an easier methodology for the variance analysis of experiments in augmented complete randomized blocks.

In order to find out the concentration of macro and micronutrients, as well the total amounts of nutrients absorved by Roma VF, of the Santa Cruz group of tomato, plants were collected from field from 15 days up to 105 days and analysed for the nutrients. At the flowering period the leaves presented the following concentration on nutrients: 3.7% N; 0.5% P; 3.2% Ca; 0,9% Mg; 0,4% S; 72 ppm B; 15 ppm Cu; 434 ppm Fe; 375 ppm Mn; 0.1 ppm Mo and 148 ppm Zn. A production of 65 t/ha effective hasrvested content: 67.8 kg N; 8.9 kg P; 112.2 kg K; 7.7 kg Ca; 6.0 kg Mg; 3.1 kg S; 93 g B; 45 g Cu; 547 g Fe; 163 g Mn; 485 mg Mo; 321 g Zn.

Com a finalidade de se verificar a influência do volume de terra disponível no desenvolvimento vegetativo da berinjela (Solanun melongena L.), conduziu-se um ensaio, em condições de casa de vegetação, no Setor de Horticultura da E.S.A, "Luiz de Queiroz", em Piracicaba, SP, utilizando-se da cultivar híbrida F 100. Foram utilizados recipientes (vasos) de 5 tamanhos diferentes: 200, 450, 3000, 4750 e 9000 cm³ de capacidade. Através dos resultados obtidos pode-se concluir que: quanto maior o recipiente utilizado maior o desenvolvimento vegetativo da beringela, até um ponto em que poderia haver uma menor produtividade por unidade de área plantada. Para a berinjela, há a necessidade de recipiente que corresponda a uma capacidade de, no mínimo, 4750 centímetros cúbicos de substrato.

Com a finalidade de se evitar a operação de desbrota manual em plantas de fumo (Nicotiana tabacum L.), controlando a brotação axilar, conduziu-se um experimento, em Piracicaba (SP), em condições de campo, utilizando-se um inibidor de brotação, o 4-(1,1-dimetiletil)-N-(1-metilpropil)-2,6-dinitrobenzenamina (butralin), nas concentrações de 1, 2 e 3% do produto comercial, na dose de 20 ml da emulsão por planta, aplicada logo após a retirada da inflorescência principal, na extremidade superior da haste atingindo as gemas axilares uniformemente. Os resultados mostram que o butralin, nas concentrações utilizadas, em comparação com o controle, promove a inibiçao no desenvolvimento dos meristemas das gemas axilares, sem afetar o desenvolvimento das folhas. A concentração de 2% do produto comercial, foi a que proporcionou maior peso de matéria seca de folhas e menor de matéria seca de brotos. Os resultados mostram que o butralin, nas concentrações utilizadas, em comparação com o controle, promove a inibiçao no desen volvimento dos meristemas das gemas axila-res, sem afetar o desenvolvimento das folhas. A concentração de 2% do produto comercial, foi a que proporcionou maior peso de materia seca de folhas e menor de materia seca de brotos.

(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.

The present work was carried out in order to study: 1. identification of deficiencies symptoms of N, P, K, Ca, Mg and B. 2. The effect of the deficiency of each macronutrient and boron on the chemical composition of the plants. Young Solanum jilo var. Morro Grande Oblongo plants were grown in pots containing pure quartz. Twice a day, the plants were irrigated by percolation with nutrient solutions. The treatments were: complete solution and deficient solutions, in which each of the macronutrients or boron was omited. When the malnutrition symptons appeared the plants were harvested and divided into: superior and inferior leaves and stalk. The dry matter was analysed chemically for N, P, K, Ca, Mg and B. CONCLUSIONS - Symptons of malnutrition were observed for N, P, K, Ca. Mg, B. - High rate of multiplicaiton of Tetranychus urticae was observed on plants deficient in potassium. - Nutrient content expressed in porcentages and in ppm for boron in the ripened leaves of plants cultivated under normal conditions and under deficient conditions were.

Seeds of the legumes where sowed in an Alfisol (Terra Roxa Estruturada) well supplied in nutrients. In order to find out the concentrations of the macronutrients as well the total amounts of nutrients absorved by the legumes, plants were harvested from 21 days after germinated up to 147 days. The plants were divided into leaves and stems and analysed for N, P. K, Ca, Mg and S by conventional methods. Digestibility test "in vivo" was carried out for the differents stages of development of the legumes. The authors concluded: - Maximum dry matter production was obtained by perennial soybean plants, followed by centro and siratro, between 134 and 140 days. - The maximum velocity of growth happen at 83 and 91 days for the three species. - The highest concentration of potassium was found in the legumes. - The maximum aounts of macronutrients extracted by the legumes are: CENTRO PERENNIAL SOYBEAN SIRATRO - The digestibility test by the nylon bag techniques (dry matter) showed differences between the stems and leaves. - The digestibility increased with the age for centro and siratro. - For perennial soybean the minimum of digestibility at 74 days (33.2%) for the stems and at 88 days (30.2%) for the leaves. - After 42 days the digestibility increased up to the 147 days for centro and stratro. - At 147 days the digestibility of dry matter for perennial soybean was 58.9%, for siratro 56.5% and for centro 44%.

This research deals with the effects of exogenous growth substances on germination of cotton 'IAC - 17'. 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, indoleacetic acid (IAA) 100 ppm, and water as check treatment. CCC 2000 ppm delayed germination of cotton, reducing plant development. Soaking cotton seeds in GA at a concentration of 100 ppm before planting were found to result in a more rapid growth and that the germination is hastened. SADH 4000 ppm reduced the growth of the seedlings and IAA 100 ppm did not alter the germination or the development of cotton seedlings in relation to control.

A utilização de inibidores do crescimento de plantas tem sido uma prática interessante para a manutenção de sebes em condições adequadas por períodos mais longos de tempo após a realização da poda. Para se determinar a melhor concentração de hidrazida maleica que promovesse inibição no desenvolvimento da cerca viva de Murraya paniculata, aplicou-se, sob a forma de pulverização, 30 dias depois da poda, MH-30 (sal dietanolamina de 6-hidroxi-3-(2H)-piridazinona) nas dosagens de 500, 750, 1000 e 1250 ppm, além do controle. Com a finalidade de estabelecer as variações promovidas pelo inibidor de crescimento, efetuou-se a poda das plantas 130 dias após a aplicação do regulador de crescimento, determinando-se o peso da materia seca da folhagem cortada. Os resultados obtidos mostraram que MH 1000 e 1250 ppm reduziram significativamente o desenvolvimento das plantas em relação ao controle, sendo que as concentrações de 500 e 750 ppm não promoveram variações no crescimento da folhagem comparativamente às plantas não tratadas. Estes resultados sugerem a possibilidade da utilização da hidrazida maleica como uma prática que poderia substituir o controle mecânico do crescimento na manutenção de sebes, desde que aplicada em concentrações inibitórias ao desenvolvimento mas que não promovam sintomas de fitotoxidade.

This paper deal with pollen grain characteristics of 14 species of Compositae honey plants more frequently in pollen analysis of honey bees (Apis mellifera L.) and colleted by them. We present a key for separation and identification of those honey plants by pollen characteristcs.

Foram estudados para 4 cultivares de laranjas-doces, a utilização do mesmo tecido somático, porém de duas origens - do clone velho original e do nucelar na obtenção de mudas de Citrus. Observou-se influência das borbulhas de origem nucelar no vigor das mudas e sua expressão de juvenilidade através da presença de espinhos. Confirmou-se que a presença de espinhos está ligada à fase juvenil e não ao vigor vegetativo.

Estudou-se a persistência da fase juvenil em clones de Citrus expressa pela presença de espinhos. Os 8 clones observados pertencem à coleção básica de matrizes nucelares do Instituto Agronômico de Campinas. A verificação dos espinhos foi realizada nas mudas obtidas a partir das borbulhas retiradas de varias posições das arvores matrizes, que tinham na oportunidade 24 e 18 ano de idade. Constatou-se a presença de tecidos juvenis em todas as mudas obtidas, com intensidade variável em função da posição da árvo re de onde se obteve a borbulha. Verificou--se ainda variação no numero e tamanho dos espinhos entre clones, provavelmente influindo nesse fator, a origem da borbulha do seedling original, e a intensidade de poda realizada nas arvores matrizes.

Tendo em vista que há lavradores que fazem o desbaste das plantas e outros não em culturas de cenoura, foi instalado um experimento na Horta Experimental do D.A.H./ESALQ, Piracicaba, Brasil, utilizando-se o cultivar Nantes, com os seguintes tratamentos: espaçamento entre-linhas de 15 cm e 30 cm, e espaçamento entre plantas de 4 cm e 8 cm após o desbaste, e sem desbaste. Os resultados mostram que o efeito da competição é maior entre plantas do que entre linhas e que para as condições normais de semeadura não há necessidade de se fazer desbaste. A produção total de raízes aumenta com a elevação da densidade. O espaçamento de 30 cm é preferível ao de 15 cm entre-linhas.

No summary/description provided

49 strawberry clones were tested for the reaction to the natural incidente of Ramularia tulasnei in field condictions, in Piracicaba, São Paulo State. The evaluation were done using a scale of 1 (denoting no infection) to 6 (indicating a severe infection) in the phase of highest severity of the disease; the clones were classified in resistants (1.00 to 2.30), moderately resistants (2.31 to 3.70), and susceptibles(3.71 to 5.00). 11 resistant clones, 31 moderately resistant, and 7 susceptible ones were identified. The resistant clones were "1-2008" (grade 1.00 ± 0.00), "IAC-2713", "Camanducaia (IAC-3530)", "A. Brucknner (1-2492)", "IAC-3113 x (IAC-2712 x 1-2008-1)-10", "IAC-4326", "IAC-3530 x IAC-2747-2", "Konwoy (1-3846)", "Atibaia (IAC--4325)", "IAC-4896-4", and "IAC-4749"; the most susceptible one was "Jundiai (IAC-4204)" (grade 5.00 ± 0.41).