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Bragantia, Volume: 12, Número: 4-6, Publicado: 1952
  • Melhoramento do cafeeiro: IV - Café Mundo Novo

    Carvalho, A.; Krug, C. A.; Mendes, J. E. T.; Antunes Filho, H.; Morais, Hélio de; Aloisi Sobrinho, J.; Morais, M. Vieira de; Rocha, T. Ribeiro da

    Resumo em Português:

    Em um conjunto de cafeeiros existentes em Mundo Novo, hoje Urupês, na região Araraquarense do Estado de São Paulo, foram feitas seleções de vários cafeeiros baseando-se no seu aspecto vegetativo, na produção existente na época da seleção e na provável produção do ano seguinte. Estudou-se a origem da plantação inicial desse café, tanto em Urupês como em Jaú, chegando-se à conclusão de que é provavelmente originário desta última localidade. Progênies do café "Mundo Novo", anteriormente conhecido por "Sumatra" e derivado de plantas selecionadas em Urupês e Jaú, acham-se em estudo em seis localidades do Estado : Campinas, Ribeirão Prêto, Pindorama, Mococa, Jaú e Monte Alegre do Sul. No presente trabalho são apenas aproveitados dados referentes à variabilidade morfológica e característicos da produção das progênies dos primeiros cafeeiros selecionados em Urupês e estudados em Campinas, Jaú, Pindorama e Mococa. Em tôdas as localidades, observou-se variação nos caracteres morfológicos das progênies, verificando-se a ocorrência de plantas quase improdutivas. A maioria das progênies, no entanto, se caracteriza por acentuado vigor vegetativo. Foram estudadas as produções totais das progénies e das plantas, no período 1946-1951, notando-se que algumas progénies se salientaram pela elevada produção em tôdas as localidades. Os tipos de sementes "moca", "concha" e "chato" foram determinados em amostras de tôdas as plantas, por um período de três anos, notando-se que a variação ocorrida é da mesma ordem que a encontrada em outros cafeeiros em seleção. Procurou-se eliminar, pela seleção, cafeeiros com elevada produção de frutos sem sementes em uma ou duas lojas, característico êsse que parece ser hereditário. Os resultados obtidos de cruzamento entre os melhores cafeeiros "Mundo Novo" de Campinas e plantas da variedade murta, indicaram que esses cafeeiros são do tipo bourbon. Provavelmente, êsses cafeeiros constituem recombinações de um cruzamento primitivo entre o café "Sumatra" e o bourbon. As progênies mais produtivas do café "Mundo Novo" e livres de vários dos defeitos mencionados, já se acham em multiplicação, a fim de, em breve, serem fornecidas sementes aos lavradores, que tanto interêsse têm demonstrado por êsse café.

    Resumo em Inglês:

    In the course of the coffee breeding project carried out at the Instituto Agronômico, outstanding progenies have been derived from mother plants selected by either of the two following methods; a) before selection, individual yield is recorded for a number of years begining with the first crop, and b) selection of mother plants is made on the basis of vegetative vigor and the crop they have at the time of selection, regardless of their previous yields. Yield data and other observations presented in this paper refer to a group of progenies derived from plants selected according to the second method. With open pollinated seeds collected the from best plants found in 1943 in a private coffee plantation at Urupês County, (formerly Mundo Novo) State of São Paulo several progenies were planted at the Experiment Stations of Campinas, Pindorama, Jaú and Mococa, with different types of soils. The original coffee plantation of Urupês had been formed with seeds collected in Mineiros do Tietê County, in a farm nearby the place where the so called Sumatra coffee (Coffea arabica var. typica) was first planted after it was privately imported from the island of Sumatra at the end of the last century. This is probably the reason why the Mundo Novo coffee, as it is called nowadays, was formerly named Sumatra de Mundo Novo. From observations on the morphological type of Mundo Novo coffee plants, it was noted that most plants in all progenies and also in private plantations are morphologically similar to the bourbon variety, while a few plants are similar to the typica variety. Artificial crosses between the highest yielding Mundo Novo plants from progenies grown in Campinas and the murta variety (ttNana) grave indication that these plants are of the bourbon type (ttNaNa) and not of the typica type (TTNaNa), as it is the case of the ordinary Sumatra coffee. It has been assumed, therefore, that the Mundo Novo coffee probably originated from a primitive natural cross between the imported Sumatra coffee and the bourbon variety, already existent in the State of São Paulo when the Sumatra coffee was introduced. The progenies of Mundo Novo coffee here studied present a majority of vigorous and productive plants and a few weak individuals with very low productivity. Total yield per plant and per progeny were analized and discussed, for the period from 1946 to 1951. It is apparent that some progenies behave equally well in all locations and that high yield variability between plants is found in all Experiment Stations. The Mundo Novo coffee does not differ from other varieties in the percentages of the commercial seed types, namely, the normal flat beans, the peaberry type, and those resulting from the simultaneous development of two or more ovules in the same fruit locule. It was found, however, that a large percentage of Mundo Novo plants regularly produce an abnormal quantity of fruits with one or two empty locules. This constitutes a defect of the Mundo Novo coffee, which probably can be overcome by selection. It seems that this defect, which is not correlated with yield, is detenruned by genetic factors. Progenies are found where the number of plants showing unusual amounts of empty fruit locules is very low, other plants being normal is this respect. The most promising Mundo Novo plants from several progenies have already been artificially self-pollinated, and the seeds thus obtained were used to plant foundation seed plots. Within a few years seeds of selected Mundo Novo coffee plants will be available to farmers in the State of São Paulo.
  • Genética de Coffea: XIV - Hereditariedade do cálice petalóide em Coffea arábica L. Var. calycanthema K.M.C.

    Carvalho, A.

    Resumo em Português:

    As espécies de Coffea, no geral, apresentam um cálice constituído de cinco sépalas muito rudimentares. Em Coffea arabica L. foi encontrado um único cafeeiro, possuindo o cálice bem desenvolvido e de natureza petalóide. A análise genética dêsse característico é discutida no presente trabalho. Verificou-se que se trata de um fator que afeta, aparentemente, apenas algumas partes da flor, sendo o cálice de natureza petalóide, o estilo e o estigma de forma e tamanho variáveis e o estigma desprovido de superfície estigmática. O ovário e o pedicelo da flor são de cor branca e se desprendem com a flor, alguns dias após a sua abertura, determinando esterilidade quase total das plantas portadoras do fator calicântema. O pólen é normal. Pelo cruzamento de plantas normais com o cafeeiro calicântema, obtiveram-se 50% de plantas normais e 50% de plantas calicântema. Êstes dados da análise genética indicam, pois, que a calicantemia é controlada por um par de fatôres genéticos, tendo as plantas com cálice normal a constituição cc e, sendo heterozigotas para êsse par de alelos - Cc, as plantas calicântema estudadas. Não se conhecem plantas de constituição CC, pois todos os cafeeiros portadores do alelo C apresentam esterilidade das partes femininas da flor. As plantas calicântema têm tôdas as flores com o cálice petalóide, e não se notaram casos de instabilidade somática do alelo C. A julgar pelos dados de cruzamento com a var. murta, o cafeeiro mostrando o característico calicântema deve ter-se originado por mutação da var. typica. Essa mutação deve ser muito rara, pois apenas uma planta foi observada entre centenas de milhares de cafeeiros que têm sido examinados, tanto em viveiros como nas plantações de café.

    Resumo em Inglês:

    Coffea arabica varieties usually develop a rudimentary calyx formed by five reduced denticles. Two exceptions however have already been found which have large sepals. In one of them the development of large sepals is controlled by a single pair of genetic factors expressing incomplete dominance in F1 (Sd sd). The other exception is the calycanthema variety which possess flowers with a large and conspicuous petaloid calyx the inheritance of which has been studied in the present paper. The size and shape or the calycanthema plants, as well as its branches and leaves, are normal and similar to those of the typica variety. The sepals are almost identical with the petals, giving the impression of a flower with two. corollas. The anthers are normal and the pollen is viable ; the style and stigma are very abnormal, the stigma usually having no papillose surface. The pedicel and the ovary are white colored and when the corolla dries the whole flower drops from the branch. The production of fruits is extremelly small. The mutant is almost completely female sterile, which is a handicap for genetic investigations. By crossing heterozygous calycanthema with normal varieties of C. arabica, an offspring is obtained which segregats into 50% of normal and 50% calycanthema plants. The symbol C was given, to the gene involved, the normal coffee plants being cc the calycanthema mutant Cc. So far no homozygous dominant plants have been found. Crosses of the calycanthema mutant with the murta variety, have indicated that the new mutant most probably derived from the typica variety. The occurrence of this mutations must be very rare, as no other case has been found among hundred of thousands of coffee plants that have been so far investigated.
  • Melhoramento do cafeeiro: V - Melhoramento por hibridação

    Krug, C. A.; Carvalho, A.

    Resumo em Português:

    A hibridação como método de melhoramento do cafeeiro, oferece amplas possibilidades que ainda se acham pouco exploradas. Para o caso da espécie C. arabica, a hibridação entre suas variedades, além de fornecer dados seguros sôbre a constituição genética, permite também a verificação de ocorrência da heterose, o melhoramento sem mudança dos caracteres das variedades, ou sintetização de estruturas genéticas novas. Os cruzamentos interespecíficos poderão contribuir decisivamente para a solução do problema da melhoria da qualidade do produto e dar indicações a respeito das relações das várias espécies e da reação dos fatôres genéticos de uma espécie em ambientes genéticos diversos. Cêrca de 2500 híbridos se acham em estudo na Secção de Genética, envolvendo plantas da mesma variedade, plantas de variedades diferentes e cafeeiros pertencentes a espécies distintas. As diversas possibilidades dêsses cruzamentos no melhoramento do cafeeiro são indicadas, chamando-se especial atenção para os híbridos interespecíficos, principalmente aquêles que envolvem a espécie tetraplóide C. arabica e outras espécies diplóides, como C. canephora, C. Dewevrei e C. congensis. Êstes híbridos triplóides, após duplicação do número de cromosômios, poderão constituir fonte de novas formas de Coffea, permitindo a expansão do cultivo do café era São Paulo.

    Resumo em Inglês:

    Artificial hybridization in coffee breeding offers possibilities that are still unexplored. Inter-varietal hybridization has been used in Coffea arabica in order to get information about the genetic constitution of the varieties, and occurrence of heterosis, to breed without changing the morphological characters of the varieties and also to synthesize new genetic types of economic value. Inter-specific hybridization has been employed for improvement of cup quality and to furnish data about the relationship of various coffee species and the behaviour of known genetic factors of one species in the genetic background of other coffee species. About 2500 inter-varietal and inter-specific artificial hybridization have been made in Campinas during the last 20 years. The economic value of some of these hybrids has been stressed in this paper and special attention has been called to the inter-specific hybrids involving the tetraploid C. arabica and other known diploid species as C. canephora, C. Dewevrei and C. congensis. After chromosome doubling of these triploid hybrids, the resulting allopolyploids may be of economic value.
  • Observações citológicas em Coffea: XIX - Microsporogênese em Coffea dewevrei

    Medina, Dixier M.

    Resumo em Inglês:

    Coffea Dewevrei De Wild, et Th. Dur. is a diploid species with 2n = 22 chromosomes. Details on the microsporogenesis are presented in this paper. From pachynema to diakynesis the 11 bivalents were well differentiated into achromatic and chromatic regions : the centromere was in all chromosomes surrounded by deeply chromatic zones. Only one pair of chromosomes was found to be attached to the nucleolus; it has a submedian centromere, the organizing region seeming to be located in the short arm. Chiasmata were seen in diakynesis and metaphase I; in this later stage they were studied in detail and the chromosomes were classified as follows : a) 1 longer pair with 3 chiasmata; b) 2.7 pairs (average) with 2 chiasmata ; c) 7.3 pairs (average) with 1 chiasma. The 2-chiasmata chromosomes were of two kinds : "symmetric" and "assymmetric", depending on the position of their chiasmata in relation to the centromere. The anaphase is normal, pollen grains having 11 chromosomes. Very seldon are pollen grains formed with 10 or 12 chromosomes. First mitosis in the microspores occurs before pollen shedding. It was concluded that microsporogenesis in the coffee plants studied is normal.
  • Genética de Coffea: XV - Hereditariedade dos característicos principais de Coffea arabica L. Var. semperflorens K.M.C.

    Carvalho, A.; Krug, C. A.

    Resumo em Português:

    No planalto de São Paulo, o cafeeiro normalmente floresce duas a quatro vezes por ano, nos períodos compreendidos entre fins de julho a novembro. Raramente floresce mais vêzes, e um pouco além dessa estação. Em 1934, foram encontrados alguns cafeeiros da espécie C. arabica, caracterizados por seu florescimento quase que continuamente durante o ano. A êsse mutante foi dada a denominação de semperflorens. Os resultados da análise genética apresentados indicam que os característicos principais do semperflorens, a forma da planta, tipo de ramificação e florescimento quase que contínuo, são controlados por um par de fatôres genéticos recessivos. Êsse fator genético tem por símbolo sf sf, correspondente à abreviação da palavra semperflorens. Os resultados dos cruzamentos entre o semperflorens e as variedades murta e nana indicam que o semperflorens deve ter-se originado como uma mutação recessiva do bourbon. Apesar de terem sido encontrados cafeeiros semperflorens quase que simultâneamente em Ribeirão Prêto e Campinas, é mais provável que a mutação tenha ocorrido em Ribeirão Preto, onde o café bourbon foi cultivado pela primeira vez em São Paulo. Além de apresentar o semperflorens interêsse do ponto de vista fisiológico, tem também valor econômico, por ser produtivo e possuir boa resistência à sêca, motivo pelo qual numerosas progênies dêsse cafeeiro vêm sendo estudadas, visando o isolamento de linhagens ainda mais produtivas.

    Resumo em Inglês:

    Under normal environmental conditions coffee plants in the State of São Paulo flower two to four times during the period of July to November. Only rarely do they flower beyond these limits. In 1934 a few coffee plants of the species C. arabica were found which flower almost at any period of the year. This mutant was named semperflorens. The results of the gene tical analysis here presented indicate that the characteristics of this mutant are controled by one pair of recessive factors (sf sf). This pair of genes controls the growth habit of the plant and leaf characters, its almost continuous flowering habit and its marked drought resistance. The F1 plants (semperflorens x normal) are entirely normal, the F 2 segregatir g into 3 normal and 1 semperflorens. By crossing semperflorens with the testers murta and nana, it was concluded that the new variation probably originated as a mutation from the bourbon variety. The fruits of the semperflorens plants ripen almost throughout the whole year; at two periods however, yields are higher, one of them corresponding with the normal harvest period of coffee (March-April-May), the other occuring in October-November-December. Its total annual yield is of the same magnitude as that of the bourbon variety. As the semperflorens also seems to be of certain economic value for small intensive plantations, an attempt is being made to improve its yielding capacity through regional breeding work.
  • Taxonomia de Coffea arabica L. V: algumas recombinações genéticas

    Carvalho, A.

    Resumo em Português:

    Os resultados das análises genéticas das principais variedades de Coffea arabica têm demonstrado que elas diferem da variedade typica, tomada como têrmo de comparação, apenas por um ou dois pares de fatores genéticos principais. Essas variedades de C. arabica se acham reunidas em uma coleção na Estação Experimental Central de Campinas, que atualmente conta 24 variedades. Diversas outras variedades se acham em estudo e ainda não foram descritas. Em vista de se multiplicar a espécie C. arabica, praticamente por auto-fecundação (7 a 9% de sementes são resultantes de cruzamentos naturais), sugeriu-se que, sòmente após a obtenção da forma homozigota para os fatôres genéticos principais que as caracterizam, sejam as novas variações hereditárias descritas como variedades. Durante a execução das análises genéticas, mais de uma centena de recombinações de fatôres foram obtidas, algumas das quais dão ao cafeeiro aparência bem diferente. Após apresentar os principais característicos morfológicos de algumas recombinações, chamou-se atenção para a inconveniência de virem a ser descritas como novas variedades, criando desnecessária complexidade à nomenclatura das variedades de C. arabica.

    Resumo em Inglês:

    Genetic analysis of the varieties of Coffea arabica L. revealed so far that most of them differ from the standard variety typica by one or two main pairs of genetic factors. Twenty four varieties are planted in a collection at the Central Experiment Station of the Instituto Agronômico, in Campinas. Several other varieties not yet described are being studied. It is suggested that new variations found in C. arabica, which is self-fertile and predominantly self-pollinated in nature, be described as new varieties only after the homozygous condition for the genetic factors which are responsible for their main characteristics have been observed. Haploid (monosperma) and polyploid (bullata) plants should not be considered as varieties. In order to avoid unnecessary complexity in the taxonomy of C. arabica it is also suggested that recombinations of genetic factors which are individually responsible for the main characteristics of different varieties should not be described as new varieties. More than one hundred recombinations of two pairs of factors were obtained in the course of the genetic analysis of C. arabica varieties, some of them determining striking phenotypical effects. The main features of a few recombinant types were described in this paper.
  • Melhoramento do cafeeiro: VI - estudo e interpretação, para fins de seleção, de produções individuais na variedade bourbon

    Carvalho, Alcides

    Resumo em Inglês:

    The present study was undertaken to get information on the following questions of primary importance in coffee breeding : a) the number of years during which individual plants must have their yields recorded, in order to select the best mother trees for progeny tests; b) the number of years of individual progeny plant records, necessary for selection of the best progenies on the basis of total progeny yield ; c) the relation between the yields of mother plants and of their progenies. An attempt to answer the above questions was made through the analysis of data furnished by the Coffee Department of this Institute from a plot of 1107 plants (1 hectare), of Coffea arabica, var. bourbon, planted in 1930 for mother tree selection and individual plant recording. These plants have now 19 consecutive years of individual yield records, and some of them have progenies with 12 to 15 years of yields available for the scope of this investigation. From the study of such a group of mother trees and of their F1 progenies, the following conclusions can be drawn, assuming that the best plants are in fact those which have the highest total yields up to the present time : a) Selection of high yielding coffee mother trees is most efficient when they are already fully grown, on the basis of at least 14 years of production. Selection at early ages is not so effective. b) The efficiency is approximately the same whether the selection is based on total yield after 14 years, or when it is based on the latest biennial yield, such as the 13th plus the 14th, or even when only a single high yield of a late year is considered. This conclusion was drawn from the number of plants which, belonging to the 25 and 100 best after 19 years of yield, were found among the 25 and 100 best plants at different periods of time. From the 100 plants with the highest yield after 19 years, 59 were among the 100 best plants after 12 years; 71 were among the 100 best plants after 14 years, and so on (page 183). The conclusion that efficient mother plant selection in possible with basis on a single year of high yield, though valid only for the plot under investigation, has been corroborated by other results obtained in Campinas, where selection of mother trees was made in adult coffee plantations in years of high yield. c) A similar comparison for progenies, when the whole progeny total is considered at different periods of time, indicates that the best progenies reveal themselves much earlier, that is, after the first 6 years of consecutive yields. It must be pointed out, however, that this conclusion is also based on the assumption that the best progenies are those with highest total yield at the time the analysis was made. d) As in the case of mother plants, efficient individual selection within progenies must be based on a higher number of years of yield, when the plants are completely developed. e) It was found to be difficult to establish the relationship between the yields of mother plants and the total yield of their progenies. However, the available data indicate that, as a rule, exceptionally high yielding mother plants give outstanding progenies. In order to have a better insight on the value of a group of selected mother trees the study of their progenies in replicated trials is advisable. When yield data of several consecutive years are available for individual mother trees, the yield increase index, that is, the coefficient of regression of yield on years, can be useful for comparison among these plants. This index has been calculated for mother plants which have progenies at Campinas. Yield data of the next few years will probably contribute to a better understanding of the relationship between the yields of mother plants and their progenies.
  • Taxonomia de Coffea arabica L. VI: caracteres morfológicos dos haplóides

    Carvalho, A.

    Resumo em Português:

    No decorrer dos trabalhos de melhoramento do café em execução no Instituto Agronômico de Campinas, plantas haplóides foram encontradas nas variedades typica, bourbon, maragogipe, semperflorens, laurina, erecta, caturra e San Ramon, da espécie Coffea arabica. Todos os haplóides apresentam porte menor e fôlhas mais estreitas e mais finas do que as variedades que lhes deram origem. Apesar de as flores serem completas, nota-se esterilidade muito acentuada. Raramente se formam alguns frutos, e êstes são providos de uma única semente, motivo pelo qual as plantas haplóides são denominadas "monosperma". Os fatôres genéticos dominantes maragogipe (Mg), erecta (Er), caturra (Ct) e San Ramon, bem como os gens recessivos semperflorens (sf), e laurina (lr), das variedades estudadas, manifestam-se nas plantas haplóides, de modo semelhante ao que ocorre nas plantas diplóides correspondentes. O fator para coloração bronze dos brotos novos tem dominância incompleta e, na condição heterozigota (Brbr), mostra intensidade intermediária de côr. Nas plantas haplóides contendo um só alelo Br, a côr dos brotos novos é bronze-clara. Uma única dose do fator Na, que também apresenta dominância incompleta, dando, na forma heterozigota (Nana) e na presença de tt, o fenótipo conhecido por murta, manifesta-se, na forma haplóide, dando plantas semelhantes às homozigotas ttNaNa, apenas com fôlhas mais estreitas e mais finas. Chamou-se atenção para as linhas puras de café obtidas pela duplicação do número de cromosômios dos haplóides e sua aplicação nos ensaios de linhagens e na determinação das taxas de mutação. As observações realizadas na meiose da espécie C. arabica, bem como os dados das análises genéticas e as observações feitas nesses haplóides parecem indicar que, se essa espécie fôr alotetraplóide, tal origem deve ser bem antiga, comportando-se hoje a espécie C. arábica, como um diplóide normal. As plantas monosperma, bem como as plantas bullata, podem ser encontradas em qualquer variedade de café, motivo por que não devem ser consideradas como variedades, mas, apenas, como haplóides ou poliplóides das variedades de que se originaram.

    Resumo em Inglês:

    Haploid plants were found in progenies of the following varieties of Coffea arabica : typica, bourbon, maragogipe, semperflorens, laurina, erecta, caturra and San Ramon. These haploids resemble the normal plants from which they have originated ; they are reduced in size, their branches are more slender and the leaves are narrower and thinner. Flowers are normal, smaller, with very low fertility, due to abnormal meiosis. The dominant genetic factors maragogipe (Mg), erecta (Er), caturra (Ct), and San Ramon, and the recessive factors semperflorens (sf) and laurina (lr) have the same phenotypical expression both in haploid and normal plants. The Br (bronze young leaves) gene shows incomplete dominance, the heterozygous plants having light bronze tips; the haploid with a single dose of Br has also a light bronze color of the young leaves. In the presence of tt the Na gene is incompletely dominant the heterozygotes having the murta phenotype (ttNana). Haploids derived from bourbon (ttNaNa), therefore hemizygotes t Na, do not resemble murta but bourbon. Attention was called to pure lines obtained through duplication of chromosome number of haploids, for use in progeny tests, in order to measure the environmental variation, and also to determine mutation rate in C. arabica. Observation on meiosis and the results of genetic analysis have already pointed out that C. arabica is probably an allotetraploid of ancient origin ; this has been confirmed by the study of the haploids here described. Monosperma coffee plants with 22 somatic chromosomes, and the bullata types with 66 or 88 chromoeomes, should not be considered any more as varieties of C. arabica, but only as haploids or polyploids of the varieties from which they originated.
Instituto Agronômico de Campinas Avenida Barão de Itapura, 1481, 13020-902, Tel.: +55 19 2137-0653, Fax: +55 19 2137-0666 - Campinas - SP - Brazil
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