Trials were established on four soil types (Latosolic B Terra Roxa - LR; Ortho Dark Red Latosol - LE and Red Yellow Podzolic Laras variation - PVls in the state of São Paulo and Textural B Terra Roxa - TE in Parana to study varietal and soil effects on macronutrient composition of sugarcane leaves and to do a nutritional survey of varieties by foliar analysis. A randomized block designwas used with four replications of 16 varieties (CB 41-76; CB 45-155; CB 47-355; CB 49-260; CB 56-171; CB 61-80; IAC 50/134; IAC 51/205; IAC 52/150; IAC 52/326; Co 740; Co 775; CP 51-22 and NA 56-62). Varieties were planted under the same conditions of climate, fertilization, tillage and age, sanitation and source. A central 20 cm portion of each +3 leaf was taken (except for midrib for determining amounts of N, R, K, Ca, Mg and S, expressed -on a dry weight basis. Leaf samplesof 20 leaves per plot were selected at four months of age, for analysis. From the results obtained it was conclued that: a) There is a varietal effect on leaf composition of major elements, independent of soil type; b) Soil type has an influence on leaf composition of different varieties; c) The higher nutrient levels in the leaves did not always result in the highest production intpol/ha; d) Because of soil and varietal influence on leaf composition it is rifficult to generalize critical nutrient, levels obtained from foliar diagnosis; e) Critical levels of nutrients obtained from foliar diagnosis for une variety do not represented the same levels for all varieties. | Com o objetivo de se estudar o comportamento varietal e do solo na concentração de macronutrientes nas folhas de cana-de--açúcar e, ao mesmo tempo, executar o levantamento do estado nutricional das variedades através da análise foliar, instalaram-se ensaios em quatro Grandes Grupos de Solos cultivando 16 plantadas sob idênticas condições de clima, adubação, tratos culturais, idade, estado de sanidade e procedência de mudas. O delineamento estatístico foi o de blocos ao acaso com 16 tratamentos (variedades) e 4 repetições. Realizou-se a amostragem foliar aos 4 meses de idade, tomando-se os 20 cm centrais da folha +3 (20 por parcela), desprezando-se a nervura principal. Determinaram-se os macronutrientes (nitrogênio, fósforo, potássio, cálcio, magnésio e enxofre) os quais foram expressos em percentagem de matéria seca. Os ensaios foram colhidos aos 18 meses de idade, sendo que para cada um deles determinou-se as produtividades em toneladas por pol/ha.

An experiment was carried out with "santa-rosa, "viçoja", and "IAC-2" soybean varieties (Glycine max (L.) Merril), in nutrient solution (Leonard jars) with the objectives of pre-selection of thirteen Rhizoblum japonicum strains, and verification of the degree of specificity of the soybean varieties. After a fifty eight days growth period it was observed, from the nitrogen fixed, that strains n.° SMS-64, SMS-65, SMS-68, SMS-309, and SMS-310 were equally efficient on the three varieties. Some strains were efficient in two, and others in only one variety. Strain SMS-333 did not form nodules on "IAC-2", but was efficient on the other varieties. The total plant dry weight was not as good criteria as the total nitrogen, for the strain differentiation, although total nitrogen and dry weight were correlated. Nodulation (nodule number, or dry weight) was not a good criterion for strain selection. | Um experimento foi conduzido em casa de vegetação, em vasos de Leonard com solução nutritiva sem nitrogênio, em condições assépticas, com os objetivos de pré-selecionar treze estirpes de Rhizobium japonicum e verificar o grau e especificidade das variedades santa-rosa, viçoja e IAC-2 (Glycine max (L.) Merril.). Pela observação do nitrogênio total fixado aos 58 dias, verificou-se que as estirpes SMS-64 (= 513 Re, RS), SMS-65 (= 519 Re, RS), SMS-68 (= 532c, RS = PR-G3, IBPT, PR) SMS-309 e SMS-310, são igualmente eficientes nas três variedades. Houve correlação entre o peso seco das plantas e o nitrogênio fixado, porém a diferenciação das estirpes pelo peso seco das plantas perdeu em sensibilidade. A nodulação não foi critério satisfatório para separar estirpes eficientes. Para o conjunto de estirpes eficientes em pelo menos uma das variedades estudadas, verificou-se que viçoja apresentou menor especificidade, estabelecendo simbiose eficaz com nove das estirpes testadas.

This work was designed to study the effect of copper in the medium on growth and mineral composition of the coffee plant, bearing in mind the possibility of accumulation of toxic residues in the soil as a consequence of the treatments against rust. Young plants of the varieties Mundo Novo and Catuái were grown in nutrient solution in the presence of Cu concentrations from 0.02 to 200 ppm. Toxic effects were found to be darkening and cessation of root growth; wilt, necrosis and leaf drop; abnormalities in the epidermis, parenchyma and chlorophasts. The threshold level for copper toxicity is around 30 ppm in the leaves. Mundo Novo seems to be more sensitive to copper toxicity. Under soil conditions it was found that the joint use of lime and stable manure eliminates the toxicity of an application of 200 ppm of cooper. | Foi estudado o efeito do cobre do substrato no crescimento, sintomatologia e composição mineral do cafeeiro novo. Verificou-se ser a var. Mundo Novo mais sensível à toxidez do cobre por translocar maior proporção do elemento que a var. Catuaí. O uso de calcário e de matéria orgânica no solo neutraliza o sobre tóxico.