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Seed Size as Key Factor in Germination and Seedling Development of Copaifera langsdorffii (Fabaceae)  [PDF]
Matheus Lopes Souza, Marcílio Fagundes
American Journal of Plant Sciences (AJPS) , 2014, DOI: 10.4236/ajps.2014.517270
Abstract:

Seed size is a plastic trait of the plants that directly affect seed germination and seedling recruitment. This study aimed to investigate the relationship between seed size, seed germinability and seedling performance of Copaifera langsdorffii by testing four hypotheses: 1) larger seeds have higher germination percentage; 2) smaller seeds require less time to germinate and for initial development of the seedlings; 3) larger seeds produce more vigorous seedlings and 4) seed size negatively affects seedling root/shoot ratio. In 2011, we selected 30 individuals of C. langsdorffii from which 300 seeds were randomly collected in the plant canopy. All these seeds were weighted and placed in germination tray using vermiculite as substrate. Seed germinability and initial development of seedlings were monitored daily until cotyledons fell. Small seeds have higher germination percentage and germinate faster when compared to large seeds. Nonetheless, seedlings originated from larger seeds have longer development times, resulting in more vigorous seedlings. In addition, seedlings originating from small seeds allocate proportionally greater amount of resources to roots when compared to larger seeds. The fact that small seeds have higher germination percentage and faster germination favors the colonization of transient habitats. However, larger seeds produce more vigorous seedlings, favoring the seedling establishment in more stable habitats. Thus, we argue that high variability in seed size of C. langsdorffii favors its widespread geographic distribution.

Arquitetura da planta e diversidade de galhas associadas à Copaifera langsdorffii (Fabaceae)
Costa,Fernanda Vieira da; Fagundes,Marcílio; Nieves,Frederico de Siqueira;
Ecolog?-a austral , 2010,
Abstract: plant architecture and gall diversity associated with copaifera langsdorffii (fabaceae). galling insects induce tumors on their host plants in response to climatic adversities and as a protection against natural enemies. among several hypotheses that explain differences in the distribution and abundance of galling-inducing insects, the plant architecture hypothesis stresses the influence of host plant architecture (e.g., a combination of life form, plant height, and number of shoots, branches and leaves in relation to crown volume). the aims of this study was to evaluate the effects of host plant architecture on gall species diversity and to determine the sample effort to perform a representative collect of the galling insects fauna. on fifty c. langsdorffii trees, we determined both architectural variables (i.e. height, dbh, number of ramifications of the first, second and third level, and crown area and plant volume) and gall richness and abundance. we found a total of 23 gall morphotypes associated with host plant c. langsdorffii. the gall richness and abundance were not affected by host plant architecture. rarefaction curves indicated that ten individuals and 14 shoots per plant are sufficient to sample all gall morphotypes associated with c. langsdorffii. the study suggest a new methodology to sampling galls in this tropical tree species.
Altera??es estruturais e fisiológicas em sementes de Copaifera Langsdorffii DESF. - Leguminosae-Caesalpinioideae submetidas ao tratamento com hipoclorito de sódio
Noleto, Leonardo Gon?alves;Pereira, Maria de Fátima Rodrigues;Amaral, Lourdes Isabel Velho Do;
Revista Brasileira de Sementes , 2010, DOI: 10.1590/S0101-31222010000100005
Abstract: we determined the effect of sodium hypochlorite (naclo) immersion on the seed coat, germination and establishment of seedlings of copaifera langsdorffii desf. (copaiba; diesel tree; kerosene tree; langsdorf's copaifera). cuticle removal of the seed coats treated with 2.5% naclo was shown by sudan iv staining and scanning electronic microscopy. treatment with naclo increased water uptake by the seeds during the early stages of imbibition. the cell walls of cotyledons stained with ferric chloride showed phenolic compounds with putative inhibitory proprieties upon germination. immersion in naclo was the treatment most favorable to seedling emergence (54%) when compared to mechanical scarification (2%) and untreated control seeds (14%). these results indicate that naclo is an efficient option for large-scale seedling production, principally due to its antiseptic proprieties.
Influence of leaflet age in anatomy and possible adaptive values of the midrib gall of Copaifera langsdorffii (Fabaceae: Caesalpinioideae)
de Oliveira,Denis Coelho; dos Santos Isaias,Rosy Mary;
Revista de Biología Tropical , 2009,
Abstract: gall inducing insects most frequently oviposit in young tissues because these tissues have higher metabolism and potential for differentiation. however, these insects may also successfully establish in mature tissues as was observed in the super-host copaifera langsdorffii. among c. langsdorffii gall morphotypes, one of the most common is a midrib gall induced by an undescribed species of cecidomyiidae. following this ?host plant and gall-inducing insect? model, we addressed two questions: 1) do the age of the tissues alter the gall extended phenotype? 2) do gall morphological and anatomical features influence the adaptive value of the galling insect? for anatomical and histometrical studies, transverse sections of young and mature, galled and ungalled samples were prepared. galls in young leaflets presented higher potential for cell division and greater nutritive reserves, whereas galls in mature leaflets perhaps provide more protection against natural predators and desiccation. host organ age at the time of oviposition may influence plant cell fates and consequently the interpretation of the adaptive value of insect galls. rev. biol. trop. 57 (1-2): 293-302. epub 2009 june 30.
Influence of leaflet age in anatomy and possible adaptive values of the midrib gall of Copaifera langsdorffii (Fabaceae: Caesalpinioideae)  [cached]
Denis Coelho de Oliveira,Rosy Mary dos Santos Isaias
Revista de Biología Tropical , 2009,
Abstract: Gall inducing insects most frequently oviposit in young tissues because these tissues have higher metabolism and potential for differentiation. However, these insects may also successfully establish in mature tissues as was observed in the super-host Copaifera langsdorffii. Among C. langsdorffii gall morphotypes, one of the most common is a midrib gall induced by an undescribed species of Cecidomyiidae. Following this ‘host plant and gall-inducing insect’ model, we addressed two questions: 1) Do the age of the tissues alter the gall extended phenotype? 2) Do gall morphological and anatomical features influence the adaptive value of the galling insect? For anatomical and histometrical studies, transverse sections of young and mature, galled and ungalled samples were prepared. Galls in young leaflets presented higher potential for cell division and greater nutritive reserves, whereas galls in mature leaflets perhaps provide more protection against natural predators and desiccation. Host organ age at the time of oviposition may influence plant cell fates and consequently the interpretation of the adaptive value of insect galls. Rev. Biol. Trop. 57 (1-2): 293-302. Epub 2009 June 30.
Semi-hypogeal germination in Pachyrhizus ahipa (Wedd.) parodi (Fabaceae: Phaseoleae): seedling and sapling morphology
Milanez, Camilla R. Dias;Oliveira, Denise M. Trombert;Moraes-Dallaqua, Marina A.;
Brazilian Archives of Biology and Technology , 2008, DOI: 10.1590/S1516-89132008000200015
Abstract: the aim of this work was to describe the morphology of seedlings and saplings of pachyrhizus ahipa, a cultivated species of phaseoleae (fabaceae), analysing the seedling type and characterizing the structure of cotyledons, eophylls and metaphylls. it was observed that the seedling was semi-hypogeal, a germination type not yet recorded for the phaseoleae tribe. it formed two opposite and unifoliated eophylls with an evident pair of stipels. metaphylls were trifoliolate and had alternate phyllotaxis. both eophylls and metaphylls were pinnate, camptodromous, and brochidodromous.
Germination, Vigor of Seeds and Emergence of Fabaceae Seedling in Bovine Faeces  [PDF]
Renata Vianna Lima, Henrique Duarte Vieira, Francielle de Souza Guimar?es, Nardele Moreno Rohem Jr., Tatiana Oliveira da Silva, Alberto Magno Fernandes, Cynthia Pires Guimar?es, Amanda Justino Acha, Bruno Borges Deminicis
American Journal of Plant Sciences (AJPS) , 2014, DOI: 10.4236/ajps.2014.514230
Abstract:

This study was conducted to evaluate the physiological quality of forage seeds after passage through the gastrointestinal tract of cattle, as well as the emergence of seedlings derived from these seeds. Three Fabaceae species were used: tropical kudzu, leucaena and calopo. One hundred grams of seeds of each species were offered, separately, to five bovines. After the start of the dispersion, the faeces of the animals were collected every 6 hours, in a total of 72 hours, being taken to the greenhouse immediately after each collection. The study evaluated the total number of seedlings in the stool, the lengths of roots and aerial parts, as well as the natural and dry seedling weight thirty days after the disposal of the faeces in the greenhouse. The experimental design consisted of randomized blocks, with twelve treatments (sampling periods) and five replications (cattle). The best performance for the total number of seedlings in the faeces of cattle was observed in the kudzu species. The length of the root, length of the aerial part and dry matter seedling weight was observed in the leucaena species, followed by kudzu. The calopo showed low results for all variables due to the high degradation of the seeds.

Eletroforese de proteínas e isoenzimas em sementes de Copaifera Langsdorffii Desf. (leguminosae caesalpinioideae) envelhecidas artificialmente
Carvalho, Dulcinéia de;Ferreira, Robério Anastácio;Oliveira, Luciana Magda de;Oliveira, Alessandro Fabiano de;Gemaque, Rin? Celeste Rodrigues;
Revista árvore , 2006, DOI: 10.1590/S0100-67622006000100003
Abstract: electrophoresis has been used to aid the evaluation of physiological seed quality of forest species, as isozymes provide fast responses. seeds of copaiba (copaifera langsdorffii) were artificially aged for 0, 24, 48, 72 and 96 hours, in a germination chamber (42o c and 100% ur). the objective of this research was to evaluate possible changes in the electrophoretic patterns of proteins and isozymes during the artificial aging. the artificial aging reduced the germination and vigor of c. langsdorffii seeds, but vigor was affected faster than germination. the electrophoretic patterns showed no difference in the content of soluble and storage proteins, but for esterase and peroxidase isozymes there was reduction in the activity with aging.
Spatial heterogeneity and its influence on Copaifera langsdorffii Desf. (Caesalpiniaceae)
Resende, Júlio Carlos Fran?a;Klink, Carlos Augusto;Schiavini, Ivan;
Brazilian Archives of Biology and Technology , 2003, DOI: 10.1590/S1516-89132003000300012
Abstract: population dynamics and structure of young individuals of the tree copaifera langsdorffii desf. (caesalpiniaceae) were studied in the gallery forest of the panga ecological station, uberlandia, mg, brazil. three distinct habitats were recognized in this forest, dike, middle and edge zone. four annual surveys of plant height, diameter at plant base and density were made between 1993 and 1996. the species showed an aggregated distribution in all three habitats. population structure in all four surveys presented the typical reversed "j" form, characteristic of populations in local regeneration. for the whole population, mortality rates during the four years were constant and low (average of 4.8 % per year), while recruitment declined during the same period (average of 2.9 % per year). the c. langsdorffii seedling and sapling intraspecific density had a negative effect on growth, possibly due to the action of herbivores and pathogens.
Spatial heterogeneity and its influence on Copaifera langsdorffii Desf. (Caesalpiniaceae)  [cached]
Resende Júlio Carlos Fran?a,Klink Carlos Augusto,Schiavini Ivan
Brazilian Archives of Biology and Technology , 2003,
Abstract: Population dynamics and structure of young individuals of the tree Copaifera langsdorffii Desf. (Caesalpiniaceae) were studied in the gallery forest of the Panga Ecological Station, Uberlandia, MG, Brazil. Three distinct habitats were recognized in this forest, Dike, Middle and Edge zone. Four annual surveys of plant height, diameter at plant base and density were made between 1993 and 1996. The species showed an aggregated distribution in all three habitats. Population structure in all four surveys presented the typical reversed "J" form, characteristic of populations in local regeneration. For the whole population, mortality rates during the four years were constant and low (average of 4.8 % per year), while recruitment declined during the same period (average of 2.9 % per year). The C. langsdorffii seedling and sapling intraspecific density had a negative effect on growth, possibly due to the action of herbivores and pathogens.
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