|
|
|
| Registros recuperados: 16 | |
|
|
| Moreira,Sílvio; Gurgel,J. T. A.. |
| 1 - The present paper deals with the results of studies on pollen fertility, number of seeds per fruit and frequency of polyembryony in Citrus. 2 - The pollen may be divided into four groups of which the first consists of the living and functional grains, colouring deeply with carmín acetic, germinating in sugar solutions fairly well. The remainny three types : half filled grains, empty grains, and small deformed grains are all inviable. 3 - The grains are generally spherical, 15 to 40ix in diameter. The smallest grains were found in Citrus hystrix and Citrus mitis (fig. 3 and 4), while citron and the grape-fruits have the largest grains (fig. 1, 2 and 5). 4 - Size and form are reasonably constant, except the hybrid "Citran-gequat", "limão galego" without... |
| Tipo: Info:eu-repo/semantics/article |
|
| Ano: 1941 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87051941001000001 |
| |
|
|
| Gurgel,J. T. A.; Soubihe Sobº,J.. |
| 1 - This paper is a joined publication of the Dept. of Genetics, Escola Superior de Agricultura "Luiz de Queiroz", University of São Paulo, and Secção de Citricultura e Frutas Tropicais, Instituto Agronômico, de Campinas, and deal with the number of seed per fruit and the polyembryony in Citrus, with special reference to the pummelos (C. grandis). 2 - For C. pectinifera, hibrid limon x acid lime, C. histrix and Citrus sp. the mean of seeds per fruit is 5,8 - 17,3 - 30,2 -94,6; for 14 pummelos the average was 100 and the range of variation 11 to 185 seeds per fruit. For the four above mentioned Citrus the cotyledons were classified into 3 types: big (near 8 mm.), medium (near 6 mm) and small (near 4 mm) and for the pummelos there was only one size of... |
| Tipo: Info:eu-repo/semantics/article |
|
| Ano: 1951 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0071-12761951000100029 |
| |
|
|
| Gurgel,J. T. A.. |
| The general properties of POISSON distributions and their relations to the binomial distribuitions are discussed. Two methods of statistical analysis are dealt with in detail: X2-test. In order to carry out the X2-test, the mean frequency and the theoretical frequencies for all classes are calculated. Than the observed and the calculated frequencies are compared, using the well nown formula: f(obs) - f(esp) 2; i(esp). When the expected frequencies are small, one must not forget that the value of X2 may only be calculated, if the expected frequencies are biger than 5. If smaller values should occur, the frequencies of neighboroughing classes must ge pooled. As a second test reintroduced by BRIEGER, consists in comparing the observed and expected error... |
| Tipo: Info:eu-repo/semantics/article |
|
| Ano: 1945 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0071-12761945000100010 |
| |
|
| |
|
|
| Gurgel,J. T. A.; Mitidieri,J.. |
| The present work deals with the study of the effects of selfing and crossing in pures lines of okra inbred for five generations and the methods of breeding in this plant. This work is party of a large program of this Dept. to study heterosis in plants naturally self pollinated. The technic of selfing consists of tying with a string the floral bud before anthesis. To make controlled crosses, it is necessary to emasculate the flowers removing the anthers with small forceps, and to cover the flowers with a bag and wait for 1 or 2 days until the blooming. Also, the male parents are covered with paper bags prior to flowering. Finally, the pollen is brushed lightly over the stigma of the emasculated flowers and the females unit rebagged. The authors have tried... |
| Tipo: Info:eu-repo/semantics/article |
|
| Ano: 1956 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0071-12761956000100008 |
| |
|
|
| Gurgel,J. T. A.; Soubihe Sobrinho,J.; Malavolta,E.; Leme Júnior,J.. |
| In the present paper the authors deal with the content of ascorbic acid in guavas (Psidium guajava L.) and the methods of sampling used. Ascorbic acid was determined directly in the photoeletric colorimeter (EEL), after extraction with a 4 per cent solution of oxalic acid. Guavas from various parts of State of S.Paulo were used and the general mean found was around 100 mgm of ascorbic acid per 100 gm fresh weight of the material used for extraction. It was found that there is great variation in the ascorbic acid content according to the condition of the fruit: Ascorbic acid Condition content in Mean mgm/100 gm Green and hard 93,36 - 119,54 102,43 Small green 57,34 - 92,30 83,40 Firm ripe 71,28 - 115,98 90,32 Overripe 63,22 - 85,98 77,36 Of the diferent... |
| Tipo: Info:eu-repo/semantics/article |
|
| Ano: 1951 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0071-12761951000100019 |
| |
|
|
| Gurgel,J. T. A.; Leme Jr.,J.; Malavolta,E.; Montenegro,H.. |
| This paper deals with the variation of the ascorbic acid content in Natal orange as related to the type of rootstock and to the picking time. The determinations were carried out in the juice of fruits which had practically the same ratio total solids/acidity being selected only the highest values of such quotient. The results can be summaryzed as follows: 1. The rootstock has a significant influence on the vitamin C content of the scion; this influence shows two interesting aspects: first, the ascorbic acid contet itself varies as a function of the rootstock; among the three rootstocks studied the highest values were obtained on scion growing on Serra d'água orange; the lowest values were found in "limão rugoso" and "limão francês" was intermediate; the... |
| Tipo: Info:eu-repo/semantics/article |
|
| Ano: 1953 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0071-12761953000100011 |
| |
|
|
| Brieger,F. G.; Gurgel,J. T. A.. |
| 1 - The object of the present paper is the study of the effect of different rootstocks on pollen fertility of the scion. The material was obtained from experiments by Moreira (18), in progress at the Experimental Station, Limeira, São Paulo, and from experiments by Vasconcelos (1), in progress in the Experimental Orchard at Piracicaba, São Paulo. Homogeneity test of method 2 -A preliminary homogeneity test was carried out and showed that the methods for collecting and counting pollen were sufficiently satisfactory. This test consisted in the following : pollen was collected from 3 plants for each of 5 different rootstocks, budded with laranja pera and for each plant 3 determinations were made. The decomposition of the total error showed no significant,... |
| Tipo: Info:eu-repo/semantics/article |
|
| Ano: 1941 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87051941001000002 |
| |
|
|
| 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 |
|
| Ano: 1942 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87051942001200001 |
| |
|
|
| Moreira,Sílvio; Gurgel,J. T. A.; Arruda,Lineu F. de. |
| The studies on polyembryony in Citrus reported in this paper show that there is a great variability in the degree of polyembryony among the seeds, fruits and trees of a same form or variety of Citrus. Seeds from different crops of the same plant also show considerable variation in the degree of polyembryony. In order to obtain reliable data on the degree of polyembryony in Citrus the samples for study should include a great number of seeds taken from several fruits of different trees. Since there is a yearly variation on the degree of polyembryony it was found necessary to study samples from several crops. The average number of embryos was determined by direct examination of individual seeds. Determinations based on the number of plants developed from... |
| Tipo: Info:eu-repo/semantics/article |
|
| Ano: 1947 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87051947000300002 |
| |
|
| |
|
|
| Gurgel,J. T. A.; Valsechi,O.. |
| This paper is a joined publication of the Depts. of Genetics and of Technology, of the E. S. A. "Luiz de Queiroz", Universidade de São Paulo, and deals with the variation of the percentage oil content in the whole seeds, the embryos and the seed-coat of 28 varieties of castor-beans (Ricinus communis, L.). Primarily, the authors, as a justification of this paper, make reference to the applications which castor-oil has in industry, medicine, etc. In accordance with the weight of 100 seeds, the varieties of castor-beans were classified into 3 classes : small seeds (100 seeds less than 30 g), medium seeds (100 seeds between 30 g and 60) and large seeds (100 seeds more than 60 g). The percentage of oil in the seed, embryo and seed-coat, the dimensions of the... |
| Tipo: Info:eu-repo/semantics/article |
|
| Ano: 1952 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0071-12761952000100016 |
| |
|
|
| 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 |
|
| Ano: 1942 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87051942001100002 |
| |
|
|
| Soubihe Sobrinho,J.; Gurgel,J. T. A.. |
| Foi relatada o presença de algumas goiabeiras com frutos de polpa branca distribuídas em um goíabal de cêrca de 30.000 árvores com frutos de polpa vermelha, pertencente à Fábrica Peixe, em Santo Antônio do Posse, São Paulo. Desde que o caráter de polpa branca é recessivo ao caráter de polpa vermelho, a existência daquelas árvores ofereceu a oportunidade de, usando o gen responsável pelo primeiro caráter como um recessivo marcador, determinar a taxa de panmixia. Para o presente estudo colheram-se, de cada planta possuindo o gen recessivo, 3 frutos de polinização livre; semearam-se as sementes e nas plantas que dai resultaram, protocolaram-se aquelas com frutos de polpa vermelha e de polpa branca (quadro 1). A análise estatística por meio do teste de... |
| Tipo: Info:eu-repo/semantics/article |
|
| Ano: 1962 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87051962000100002 |
| |
|
|
| Gurgel,J. T. A.. |
| 1) O caráter presença de espinhos nos frutos da mamoneira é determinado por um par de fatores dominantes SS, sendo a forma recessiva ss, inerme. A interação alélica nao é bem intermediária, havendo uma predominância do fator S. Êste resultado foi anteriormente constatado por HARLAND (7), PEAT (8), DOMINGO (2), GURGEL (4) e FERNANDES (3). 2) A constatação da segregação 1 SS : 2 Ss : 1 ss foi feita após extensivas contagens de espinhos, tanto na forma paternal, como também no Fl, F2 e "back-cross". Por essas contagens foi verificado que existem variedades com números diferentes de espinhos, podendo-se distinguir dois tipos: variedades que têm muitos espinhos, com uma média aproximada de 170 espinhos por fruto e variedades que têm um número médio de espinhos,... |
| Tipo: Info:eu-repo/semantics/article |
|
| Ano: 1946 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0071-12761946000100014 |
| |
|
|
| Sobrinho,J. Soubihe; Pelegrino,D.; Gurgel,J. T. A.; Leme Júnior,J.; Malavolta,E.. |
| Êste trabalho faz parte do estudo do melhoramento genético das mirtáceas frutíferas, que vem sendo realizado pela Seção de Frutas Tropicais do Instituto Agronômiso e pela Seção de Genética da Escola Superior de Agricultura "Luiz de Queiroz", em Piracicaba. Colaboraram na parte analítica a Seção Técnica "Química Agrícola" e a Cadeira de Química, da "Luiz de Queiroz''. A extração de vitamina C foi feita num liqüidificador durante dois minutos, utilizando-se o ácido oxálico a quatro por mil como solução protetora. A determinação se fez no "EEL. portable colorimeter". A determinação do conteúdo de vitamina C no fruto integral de plantas expostas ao pleno sol revelou o seguinte : planta 1, 2147 mg/100 g ; planta 2, 2389 mg/100 g ; planta 3, 2322 mg/100 g de... |
| Tipo: Info:eu-repo/semantics/article |
|
| Ano: 1955 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87051955000100019 |
| |
| Registros recuperados: 16 | |
|
|
|
