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| Registros recuperados: 148.874 | |
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| Brieger,F. G.; Forster,R.. |
| The present paper gives some observations on the tumour formation and other abnormalities observed in the interspecific hybrids, Nicotiana glauca x N. Langsdorffii and N. glauca x N. Sanderae. Without entering into a detailed discussion of the literature and the various speculations proposed by Kostoff and Whitaker about the causes of tumour formations or on the relations between "spontaneous" and pathogenic tumours (Kostoff, Levine and others), two new observations are described. 1) The abnormalities in the two above mentioned hybrids are quite different. As already reported by other authors, the hybrids N. glauca x N. Langsdorffii are initially quite normal and vigorous, while tumours and other proliferations, on the stem, the stem base and the root... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1942 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87051942000700002 |
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| Graner,E. A.. |
| The methods used in obtaining polyploid cassava (Manihot utilissima Pohl) by colchicine treatment were described in detail. Two solutions of colchicine were tried, one at 0.5% and other at 1.0%, both giving identical results in producing many altered plants. The chromosome number of the altered plants was determined and [a correlation between chromosome duplication and increase of the major diameter of stomata was found. Size of stomata in cassava serves to identify poliploids individuals if the plant produced by treatment is not a chimera, a very frequent event in producing polyploid cassava by colchicine. It was emphasized that the plants obtained by treatment were a type of chimera, with the aerial part polyploid and the subterranean base diploid. The... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1942 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87051942000200001 |
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| Franco,Coarací M.. |
| Knudson's asymbiotic method and medium for germination of orchid seeds were used with success. Heating this medium at 100°C twice for 15 minutes with an interval of 24 hours was found to be better than to sterilize just once at 120°C. This procedure avoids the hydrolysis of the agar. The poor quality of the glass from which some test tubes were made raised the pH tabove 5.9 and this was apparently the cause of poor developmen of the seedlings. Also some toxic elements given off by the glass diffusing thru the medium might havo impaired somewhat the results obtained in the experiment. |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1942 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87051942000700001 |
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| Medina,J. C.; Jensen,G. O.; Neri,J. P.. |
| A study was made of the chemical composition of samples of the ribbons taken from the rami stalks at successive stages of growth with the object of determining the percentage oí lignin, cellulose, pectin, pentosans and of some substances not belonging to the cell wall. After an initial decrease, the percentage of ash increased as the plant grew and matured. The maximum (17,5%) was reached when the plant was 105 days old. The percentage of cellulose increased regularly and reached a maximum (38,2%) when the plant was 75 days old. Subsequently there was a decrease as the plant grew older. After an initial increase, the percentage of lignin decreased somewhat and again increased as the plant matured. The maximum (14,5%), however, was observed when the plant... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1942 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87051942001100001 |
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| Brieger,F. G.; Gurgel,J. T. A.. |
| The preliminary work with vegetables was described and special reference was-made to the group Brassica oleracea. a) Plants flowering easily in Piracicaba and probably in the whole State of São Paulo. To this group belongs the lettuce, endive, chichory, carrot, radish, kale, brocoli and cauliflower. b) Plants where special treatment is necessary for flowering, as cabbage. c) Plants that did not flower up to this moment, as Svisschard beet and beet. Three main factors contribute for the seedless condition in the group cabbage : lack of flowering, anormalities of the flowers and self-sterility. The preliminary experiments in controling these factors seem to indicate the possibility of seed production in this group. The systematics of the two species Brassica... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1942 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87051942001100002 |
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| Brieger,F. G.; Gurgel,J. T. A.. |
| The occurrence of polyembryonic seeds in Mangifera indica has been known for a long time, but nothing is known with reference to the forms cultivated in Brazil. It was found impossible to count the number of embryos in the seed, in spite of the size of both seed and embryo. But the cotyledons are in such a way twisted around each other that it is impossible to separate them. Thus it was necessary to take into acount only the embryos which were able to germinate and their number was determined after 3 and 7 months. It was necessary to dig up the seedlings and wash off all soil in order to distinguish ramifications of shoot and root from the actual polyembryony. In 7 months old seedlings a new complication arises owing to the complete fusion of their base.... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1942 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87051942001200001 |
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| Brieger,F. G.; Lima,A. Rodrigues; Forster,R.; Costa,A. S.; Santos,S. Ribeiro dos. |
| 1. Since our experiments on tobacco during the past years were greatly prejudiced by the extreme effect of the infection by the virus of the "vira-cabeça" causing the death of the great majority of the plants attacked, it was considered necessary to carry out an extensive experiment in order to determine whether there are differences: between localities, between varieties, between times of planting. Thus the experiment was carried out during 3 years in four Experiment Stations in the State of São Paulo: (Campinas, Piracicaba, Tietê e Limeira). In the first year 10 varieties were included and later on their number was reduced to 6. It was planed to sow and plant at regular time intervals and simultaneously in all Exp. Sta's, but this turned out to be... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1942 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87051942000800002 |
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| Mendes,A. J. T.. |
| The ovule of C. arabica L. consists õf a single integument and a small nucellús which disappears as the ovule matures. Three of the four macrospores resulting from the'division of the macrosporocyte, degenerate. The remaining chalazal cell gives rise to a "normal'' embryo sac, which is ready for fertilization at the time of the flower opening. Double fertilization occurs, as a rule, the day the flower opens. The embryo sac then increases in volume and compresses the inner integument cells. The outer cells of the integument, however, multiply actively, giving rise to the "perisperm". After degeneration of the synergids and antipodals, the zygote stays near the micro-pyle in a resting stage, while the primary endosperm nucleus divides. This first division of... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1942 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87051942000400002 |
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| Germek,Emílio. |
| A description is given of a new method for the production of seedlings in planting of rice strains. This method has been used these three last years in connection with the improvement work on rice in the "Instituto Agronômico". Perforated cylinders, 14 cm high and 18 cm diameter, are distributed over the seed bed and the seeds of each strain sown inside. A week afterwards the cylinders are pulled up and used again. With this method seedlings are obtained with great facility and perfect separation between strains thus avoiding mixture of seeds. |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1942 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87051942001200003 |
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| Paiva Neto,J. E. de. |
| In the beginning of this work a brief idea was given on what is understood as "clay", on the scientific methods applied to the study of the matter "clay" as well as on its conception with regard to the edaphic studies. A description is given of the methods of total and natural mechanical analyses which were employed in the agro-geological Department. The work is illustrated by a graphic showing the fractions of the mechanical analysis of the chief great soil types of the State of São Paulo. The fraction clay is then studied by chemical way in the following sequence : 1.° total chemical analysis, 2.° partial chemical analysis, 3.° chemical analysis of the Helmholz layer and 4.° study of the fixation of the ion Ca+ + in the already mentioned Helmholz layer.... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1942 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87051942001000001 |
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| Normanha,Edgard S.; Boock,Olavo J.. |
| In the present work were studied several varieties of manihot of the Ubatuba area on the north coast of the State of São Paulo. The experiments were carried out at the Experiment Station of that locality with a view to compare the production of roots and meal of each variety with that of the variety "Vassourinha", introduced in that district in 1938 by the Division of Roots and Tubers of the Instituto Agronômico. Said variety ("Vassourinha") is the most cultivated all over the State of São Paulo. Results have shown that among the eleven varieties studied the following exceeded the others as regards production of roots and meal: N.° 1 ("Vassourinha") and N.° 120 ("Santa"). Comparing these two one with another, it was found that N.° 1 surpassed N.° 120, not... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1942 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87051942001200004 |
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| Graner,E. A.. |
| The inheritance of two characters in Manihot utilissima Pohl were studied. It was found that the leaves with narrow lobes V (Fig. 1) are dominant over leaves with large lobes v (Fig. 2) and that the brown coloration of the roots M (Fig. 5) is dominant over white m (Fig. 6). These two characters segregate independently, according to the dates recorded in tables III and IV. The phenotypic expression of the form of the leaves is largely dependent from the environment, the leaves with narrow lobes being replaced by leaves with large lobes in plants transported to a shady place under big trees. (Figs. 3 and 4). Thus reduction of light causes a change of dominance. |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1942 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87051942000100002 |
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| Krug,C. A.; Mendes,P. Teixeira. |
| In the introduction to this article data are presented to show the growing economic importance of the cultivation of Ricinus in Brasil and particularly in the State of São Paulo. Following general statements regarding the botany, the origin and the geographic distribution of this genus, the investigations are outlined which are carried out by the Divisions of Genetics and Oil Plants of the Instituto Agronômico of the State of São Paulo, Brasil, to improve this important crop plant. Summarising, these investigations deal with the following subjects : a) Organisation of a large collection of types ; b) Investigations concerning the variability of the genus Ricinus c) Genetic analysis; d) Regional variety trials ; e) Improvement of the best varieties by... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1942 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87051942000500001 |
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| Krug,C. A.; Carvalho,Alcides. |
| Em artigos anteriores (1, 2) os autores demonstraram que a cor amarela dos frutos e a coloração bronzeada das folhas novas são, em Coffea arabica L, controladas, cada uma, por um único par de fatores genéticos (respectivamente xc xc e Br Br). Os híbridos F1 no primeiro caso com plantas de frutos vermelhos, e no segundo com plantas de folhas novas verdes, demonstraram tratar-se de casos em que há dominância incompleta nesta geração, os frutos híbridos possuindo uma coloração vermelho clara e as folhas novas se apresentando com uma tonalidade bronze clara. Como algumas das hibridações realizadas envolviam, ao mesmo tempo, os dois caracteres em questão, apresentou-se a oportunidade para constatar se havia ou não independência entre os dois pares de fatores... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1942 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87051942000600002 |
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| Costa,A. S.; Forster,R.. |
| The present paper deals with the virus disease of the tobacco plant recently described by Kramer & Silberschmidt (12) under the name "faixa das nervuras" (veinbanding). New host plants are added to the list of suscepts, as follows : Nicotiana repanda Willd., JV. angustifolia (*), N. Gossey Domin, N. Sanderae Hort. ex. W. Watson, N. glutinosa L., N. longiflora Cav., N. paniculata L., Lycopersicon esculentum Mill., L. pimpinellifolium Mill., and Cyphomandra betacea Sendt. Datura stramonium L., already studied by Kramer & Silberschmidt (12) and Nicotiana glauca Grah., Nicandra physaloides Gaertn., Solanum nodiflorum (**), S. nigrum L., Lactuca sativa L., Brassica oleracea L., Vigna sinensis Endl. var. Black., and Dolichos lablab L., var.... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1942 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87051942000200002 |
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| Paiva Neto,J. E. de. |
| The present work is a study of Vageler's formula y =x.S/ x+y.S for the determination of the final value of the reaction of the cation change in the sorptive complex of the soil. The author took the changeable H+ of the soil as a cation to be examined. Samples studied by the author belong to a chain (a series of soil profiles with 5 horizons each) taken from the original red soil ("terra roxa") of the Ribeirão-Preto Experiment Station. In these samples, as a rule, H+ changed could be considered = T - S, because the Al changed, as far as it existed, was traced in very low percentage, as can be seen in table I. For the determination of T - S, the author used a solution of (CH3COO)2Ca N/l (normal calcium acetate). As a mean of extraction, the percolation of... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1942 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87051942000900003 |
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| Krug,C. A.; Mendes,P. Teixeira. |
| Ninety six varieties of Ricinus communis, L. were studied as for their growth habit, height, length and number of internodes from the base of the plant to its first inflorescence, types of branching, color of branches and various characters of leaves, inflorescences, fruit clusters, fruits and seeds ; earliness ; yielding capacity and porcentage of oil in the seeds. The description of several of the quantitative characters is supplemented by numerical data, which are also presented graphically. The extreme variability of Ricinus offers excellent opportunities not only for genetical studies but also for breeding new and better varieties for cultivation. |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1942 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87051942000500002 |
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| Registros recuperados: 148.874 | |
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