• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 166
  • 143
  • 44
  • 16
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 3
  • 3
  • 2
  • 2
  • 2
  • Tagged with
  • 441
  • 123
  • 73
  • 61
  • 59
  • 59
  • 47
  • 42
  • 42
  • 41
  • 34
  • 34
  • 34
  • 34
  • 32
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
301

Avaliação da estrutura e do potencial fisiológico de sementes de crotalária por meio de recursos de análise de imagens / Evaluation of the structure and physiological potential of sun hemp seeds using image analysis

Natália Arruda 29 January 2013 (has links)
A utilização de procedimentos rápidos e confiáveis para análise de sementes é fundamental para a tomada de decisões nas diferentes etapas do processo produtivo e definição do destino dos lotes de sementes. Neste sentido, os objetivos desta pesquisa foram: a) avaliar a estrutura de sementes de crotalária, utilizando raios X para avaliação das partes da semente, identificação de possíveis danos causados por injúrias mecânicas, por percevejo e tecidos deteriorados nas sementes e sua relação com a germinação; b) verificar a possibilidade de utilização do sistema computadorizado de análise de plântulas (SVIS®) para detectar diferenças de vigor entre lotes de sementes de Crotalaria juncea, em comparação com as informações fornecidas por testes tradicionalmente utilizados para a espécie. Foram utilizadas seis lotes de sementes de crotalária do cultivar IAC-KR1, tanto para avaliação da estrutura de sementes quanto para a análise de imagens de plântulas. As análises relativas à morfologia interna das sementes foram realizadas em apenas uma época, no início da pesquisa, ao passo que aquelas relativas ao sistema computadorizado de imagens de plântulas e demais testes de vigor foram realizados em duas épocas, espaçadas de quatro meses. Inicialmente as sementes foram submetidas ao teste de raios X e ao teste de germinação. As plântulas normais, anormais e sementes mortas foram fotografadas e analisadas paralelamente às imagens radiográficas das sementes. Na segunda etapa da pesquisa, os seis lotes foram submetidos a testes de germinação e de vigor (primeira contagem de germinação, envelhecimento acelerado, emergência de plântulas em areia e condutividade elétrica). Para determinação do vigor das sementes por meio do SVIS®, as plântulas foram avaliadas aos três e quatro dias após a semeadura do teste de germinação, sendo obtidos dados referentes ao índice de uniformidade de desenvolvimento, vigor e comprimento de plântulas. Concluiu-se que a análise de imagens de raios X permite identificar danos mecânicos, por percevejo e tecidos deteriorados em sementes de crotalária e relacioná-las com a germinação; o SVIS® é uma alternativa viável para a avaliação do vigor de sementes de crotalária. / Fast and reliable procedures for analyzing seeds are fundamental for taking decisions during the different production stages and defining the destination of seed lots. Therefore, the objectives of this study were: a) to study the structure of sun hemp seeds with X-ray to evaluate the seed parts and identify possible damage caused by mechanical injuries, stink bugs and deteriorated tissues and their relation to germination; b) verify the possibility of using a computerized seedling analysis system (SVIS®) to detect differences in vigor between seed lots of Crotalaria juncea, and compare the results with those obtained from vigor tests used for the species. Six lots of the sun hemp cultivar IAC-KR1 were used to evaluate seed structure and also to analyze seedling images. The internal morphology seed was analyzed only at the beginning of the study whereas the computer analysis of seedling images and the other vigor tests were done at two different times, four months apart. The seeds were first submitted to X-ray and germination tests. Normal and abnormal seedlings and dead seeds were photographed and analyzed at the same time as the seed X-ray images. In the second stage of the study, the six lots were submitted to germination and vigor (first germination count, accelerated aging, seedling emergence in sand and electrical conductivity) tests. To determine the seed vigor using the SVIS®, the seedlings were evaluated three and four days after sowing for the germination test, when data on the uniformity development index, vigor and seedling length were obtained. It was concluded that the analysis of X-ray images is efficient for identifying mechanical damage, stink bug damage and deteriorated tissues and allowed to establish an association between their occurrence and germination; the SVIS® is a viable alternative for evaluating the vigor of sun hemp seeds.
302

Viabilidade do uso do sistema de blocos prensados na produ??o de mudas de tr?s esp?cies arb?reas nativas / Viability of the use of the system of pressed blocks in the production of seedlings of native arboreous species

Keller, Luciano 27 April 2006 (has links)
Made available in DSpace on 2016-04-28T14:56:19Z (GMT). No. of bitstreams: 1 2006 - Luciano Keller.pdf: 334126 bytes, checksum: 61f193dcc02e3911711ef2d11e41f545 (MD5) Previous issue date: 2006-04-27 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The objective was to evaluate the viability use of the system of blocks pressed for the production of seedlings of Inga marginata, Jacaranda puberula and Zeyheria tuberculosa. It was used as containers pressed block (440 cm3/ seedlings), plastic sacks (11x15 cm) and the tubetes of circular section (280 cm3). They were made evaluations of the seedlings, planting simulation in the nursery and definitive planting in the field in ciliary area to river Guand? s margins. It was used as substratum organic composition, ground coal and loamy soil, in the proportion volumetric, 6:2:2. For the making of the blocks, the substratum was moistened, put in metallic form with dimensions of: 60 x 40 x 20 cm (length, width and height) on a wood box with screen bottom (0,5 mm) and pressed by 15 minutes with a hydraulic monkey. After the presage, the blocks presented height of 12 cm. The seeds were sowed in sand and transplanted for the containers, selecting themselves plantules more homogeneous. The comparison was made by the characteristics of the produced seedlings and for his/her acting powder-planting in bags of 20 liters and in the field. At that time of expedition of the seedlings for the field (150 days after the sowing), the seedlings of the three studied species presented satisfactory growth, when produced in the system of blocks pressed unlike the seedlings produced in the tubetes, 150 days after the repicage. Seedlings of Jacaranda puberula produced in tubetes presented estiolation. That was not observed in seedlings of Inga marginata and Zeyheria tuberculosa. In condition of planting controlled seedlings of Inga marginata produced in tubetes presented smaller values of lap diameter and dry weight of the radicular system and seedlings of Jacaranda puberula produced in the pressed blocks presented smaller height values, lap diameter and dry weight of the radicular system, however that no repeating in the field. After the planting in the field mute of Jacaranda puberula produced in tubetes presented smaller survival taxes. There was not difference among the systems of production of the seedlings, when appraised the height and the diameter of lap of the plants 10 months after the planting. The system of pressed blocks was shown technically viable for the production of seedlings of native forest essences. / O objetivo do estudo foi avaliar a viabilidade uso do sistema de blocos prensados para a produ??o de mudas de Inga marginata, Jacaranda puberula e Zeyheria tuberculosa. Utilizou-se como recipientes bloco prensado (440 cm?/muda), sacos pl?sticos (330 cm3) e tubetes de se??o circular (280 cm3). Foram feitas avalia??es das mudas, simula??o de plantio no viveiro e plantio definitivo no campo em ?rea ciliar ?s margens do Rio Guandu, Serop?dica/RJ. Utilizou-se como substrato composto org?nico, moinha de carv?o e solo argiloso, na propor??o volum?trica, 6:2:2. Para a confec??o dos blocos, o substrato foi umedecido, colocado em forma met?lica com dimens?es de: 60 x 40 x 20 cm (comprimento, largura e altura) sobre uma caixa de madeira com fundo de tela (0,5 mm) e prensado por 15 minutos com um macaco hidr?ulico. Ap?s a prensagem, os blocos apresentaram altura de 12 cm. As sementes foram semeadas em areia e transplantadas para os recipientes, selecionando-se as pl?ntulas mais homog?neas. A compara??o foi feita pelas caracter?sticas das mudas produzidas e por seu desempenho p?s-plantio em sacolas de 20 litros e no campo. Na ?poca de expedi??o das mudas para o campo (150 dias ap?s a semeadura), as mudas das tr?s esp?cies apresentaram crescimento satisfat?rio, quando produzidas no sistema de blocos prensados ao contr?rio das mudas produzidas nos tubetes. Mudas de Jacaranda puberula produzidas em tubetes apresentaram estiolamento. Isso n?o foi observado em mudas de Inga marginata e Zeyheria tuberculosa. Em condi??es de plantio controlado mudas de Inga marginata produzidas em tubetes apresentaram menores valores de di?metro de colo e peso seco do sistema radicular e mudas de Jacaranda puberula produzidas nos blocos prensados apresentaram menores valores de altura, di?metro de colo e peso seco do sistema radicular, por?m isso n?o se repetiu no campo. Ap?s o plantio no campo as plantas de Jacaranda puberula produzidas em tubetes apresentaram menores taxas de sobreviv?ncia. N?o houve diferen?a entre os sistemas de produ??o das mudas, quando avaliada a altura e o di?metro de colo das plantas 10 meses ap?s o plantio. O sistema de blocos prensados mostrou-se tecnicamente vi?vel para a produ??o de mudas de ess?ncias florestais nativas.
303

An?lise dos viveiros e da legisla??o brasileira sobre sementes e mudas florestais nativas no estado do Rio de Janeiro / Analysis of the nurseries and the Brazilian law on native forest seeds and seedlings in state of Rio de Janeiro

Alonso, Jorge Makhlouta 31 January 2011 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-10-11T13:54:16Z No. of bitstreams: 1 2011 - Jorge Makhlouta Alonso.pdf: 2171400 bytes, checksum: e641011cdcb7b32ae286a3b24cb5852c (MD5) / Made available in DSpace on 2016-10-11T13:54:16Z (GMT). No. of bitstreams: 1 2011 - Jorge Makhlouta Alonso.pdf: 2171400 bytes, checksum: e641011cdcb7b32ae286a3b24cb5852c (MD5) Previous issue date: 2011-01-31 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / The demand for forest restoration projects grows increasingly in the State of Rio de Janeiro. One of the difficulties that these projects are having is the lack of knowledge about the regional offer of seedlings of native species. This study aims to evaluate the nurseries and seedling production of species from the Atlantic Forest in the state of Rio de Janeiro, as well as analyze the Brazilian legislation about production of forest seeds and seedlings. To conduct the study on legislation, researches were made in internet sites of federal agencies. The legal instruments found were discussed, considering the political and historical context of each era. For evaluation of nurseries and seedling production, was used data from the "Diagnostic of Seeds Collection and Seedlings Production in Rio de Janeiro", coordinated by the Secretariat of State for the Environment ? SEA-RJ, in partnership with other institutions. The study was conducted in the state of Rio de Janeiro from February to April 2010. In the diagnostic were included the nurseries producing seedlings of Atlantic Forest species, regardless of the amount, purpose and destination of then. The field work consisted of visits to the 70 nurseries surveyed, in which was applied an structured questionnaire addressing various topics related to the nursery and the seedling production, requested a list of the species produced, performed the photographic record of the nursery and marked its geographic coordinates. It was noted that the new legislation concerning forest seeds and seedlings established requirements for producers in order to guarantee for the consumer the identity and quality of what is produced. However, some issues need to be reviewed and best formulated aiming at reducing the "distance" between legislation and the reality of the producer of forest seeds and seedlings. The 70 nurseries are concentrated in some cities and regions, not covering the state as a whole. Regarding the administrative structure, the nurseries of the state, are mostly small sized, administered by public agencies and many of them lacks infrastructure for seedling production. Only 5 of 70 nurseries are registered to the RENASEM / MAPA as required by the current legislation. The seedlings are produced with low diversity of species, predominance of plastic bags as recipients and little technical and managerial control over the production. The data shows that the activity still have a lot to develop in the state, being necessary public policies aiming reinforce the existing nurseries, stimulate Atlantic Forest restoration plantations and, consequently, the demand for native forest seedlings / No Estado do Rio de Janeiro cresce cada vez mais a demanda por projetos de restaura??o florestal. Uma das dificuldades desses projetos ? o desconhecimento da oferta regional de mudas de esp?cies florestais nativas. O presente trabalho tem como objetivo avaliar os viveiros e a produ??o de mudas florestais da Mata Atl?ntica no Estado do Rio de Janeiro, bem como realizar uma an?lise da legisla??o federal referente ? produ??o de sementes e mudas florestais. Para realizar o estudo referente ? legisla??o foram feitas consultas na internet a sites de ?rg?os p?blicos federais. Os instrumentos legais encontrados foram discutidos, considerando o contexto pol?tico e hist?rico de cada ?poca. Para avalia??o dos viveiros e da produ??o de mudas, foram utilizados os dados do ?Diagn?stico de Coleta de Sementes e Produ??o de Mudas no Rio de Janeiro?, coordenado pela Secretaria de Estado do Ambiente ? SEA, em parceria com outras institui??es. O estudo foi realizado no Estado do Rio de Janeiro de fevereiro a abril de 2010. Foram inclu?dos no diagn?stico, os viveiros florestais que produziam mudas de esp?cies da Mata Atl?ntica, independente da quantidade, finalidade e destina??o das mesmas. A etapa de campo do diagn?stico consistiu em visitas aos 70 viveiros levantados, nas quais foi aplicado question?rio estruturado abordando v?rios temas relacionados ao viveiro e a produ??o de mudas, requerida uma lista das esp?cies produzidas, realizado o registro fotogr?fico do viveiro e marcadas suas coordenadas geogr?ficas. Observou-se que a nova legisla??o referente ?s sementes e mudas florestais criou exig?ncias para os produtores, visando garantir ao consumidor a identidade e a qualidade do que ? produzido. No entanto, algumas quest?es precisam ser revisadas e melhor formuladas visando diminuir a ?dist?ncia? existente entre a legisla??o e a realidade do produtor de sementes e mudas florestais. Os 70 viveiros est?o concentrados em alguns munic?pios e regi?es, n?o abrangendo o estado como um todo. Com rela??o ? estrutura administrativa, os viveiros do estado, s?o em maioria administrados por ?rg?os p?blicos, de pequeno porte e carecem de infraestrutura para produ??o de mudas. Apenas cinco entre os 70 viveiros est?o inscritos no RENASEM conforme exigido pela atual legisla??o. As mudas s?o produzidas com baixa diversidade de esp?cies, predomin?ncia de sacos pl?sticos como recipiente e pouco controle t?cnico e gerencial sobre a produ??o. Os dados demonstram que a atividade ainda tem muito a evoluir no estado, sendo necess?rias pol?ticas p?blicas visando fortalecer os viveiros j? existentes, estimular plantios de restaura??o da Mata Atl?ntica e consequentemente, a demanda por mudas florestais nativas.
304

An?lise dos viveiros e da legisla??o brasileira sobre sementes e mudas florestais nativas no estado do Rio de Janeiro / Analysis of the nurseries and the Brazilian law on native forest seeds and seedlings in state of Rio de Janeiro

Alonso, Jorge Makhlouta 31 January 2013 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-10-20T11:07:04Z No. of bitstreams: 1 2013 - Jorge Makhlouta Alonso.pdf: 2171400 bytes, checksum: eec9c3f847abd21fecbe9f0f7dea6dbb (MD5) / Made available in DSpace on 2016-10-20T11:07:04Z (GMT). No. of bitstreams: 1 2013 - Jorge Makhlouta Alonso.pdf: 2171400 bytes, checksum: eec9c3f847abd21fecbe9f0f7dea6dbb (MD5) Previous issue date: 2013-01-31 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / The demand for forest restoration projects grows increasingly in the State of Rio de Janeiro. One of the difficulties that these projects are having is the lack of knowledge about the regional offer of seedlings of native species. This study aims to evaluate the nurseries and seedling production of species from the Atlantic Forest in the state of Rio de Janeiro, as well as analyze the Brazilian legislation about production of forest seeds and seedlings. To conduct the study on legislation, researches were made in internet sites of federal agencies. The legal instruments found were discussed, considering the political and historical context of each era. For evaluation of nurseries and seedling production, was used data from the "Diagnostic of Seeds Collection and Seedlings Production in Rio de Janeiro", coordinated by the Secretariat of State for the Environment ? SEA-RJ, in partnership with other institutions. The study was conducted in the state of Rio de Janeiro from February to April 2010. In the diagnostic were included the nurseries producing seedlings of Atlantic Forest species, regardless of the amount, purpose and destination of then. The field work consisted of visits to the 70 nurseries surveyed, in which was applied an structured questionnaire addressing various topics related to the nursery and the seedling production, requested a list of the species produced, performed the photographic record of the nursery and marked its geographic coordinates. It was noted that the new legislation concerning forest seeds and seedlings established requirements for producers in order to guarantee for the consumer the identity and quality of what is produced. However, some issues need to be reviewed and best formulated aiming at reducing the "distance" between legislation and the reality of the producer of forest seeds and seedlings. The 70 nurseries are concentrated in some cities and regions, not covering the state as a whole. Regarding the administrative structure, the nurseries of the state, are mostly small sized, administered by public agencies and many of them lacks infrastructure for seedling production. Only 5 of 70 nurseries are registered to the RENASEM / MAPA as required by the current legislation. The seedlings are produced with low diversity of species, predominance of plastic bags as recipients and little technical and managerial control over the production. The data shows that the activity still have a lot to develop in the state, being necessary public policies aiming reinforce the existing nurseries, stimulate Atlantic Forest restoration plantations and, consequently, the demand for native forest seedlings. / No Estado do Rio de Janeiro cresce cada vez mais a demanda por projetos de restaura??o florestal. Uma das dificuldades desses projetos ? o desconhecimento da oferta regional de mudas de esp?cies florestais nativas. O presente trabalho tem como objetivo avaliar os viveiros e a produ??o de mudas florestais da Mata Atl?ntica no Estado do Rio de Janeiro, bem como realizar uma an?lise da legisla??o federal referente ? produ??o de sementes e mudas florestais. Para realizar o estudo referente ? legisla??o foram feitas consultas na internet a sites de ?rg?os p?blicos federais. Os instrumentos legais encontrados foram discutidos, considerando o contexto pol?tico e hist?rico de cada ?poca. Para avalia??o dos viveiros e da produ??o de mudas, foram utilizados os dados do ?Diagn?stico de Coleta de Sementes e Produ??o de Mudas no Rio de Janeiro?, coordenado pela Secretaria de Estado do Ambiente ? SEA, em parceria com outras institui??es. O estudo foi realizado no Estado do Rio de Janeiro de fevereiro a abril de 2010. Foram inclu?dos no diagn?stico, os viveiros florestais que produziam mudas de esp?cies da Mata Atl?ntica, independente da quantidade, finalidade e destina??o das mesmas. A etapa de campo do diagn?stico consistiu em visitas aos 70 viveiros levantados, nas quais foi aplicado question?rio estruturado abordando v?rios temas relacionados ao viveiro e a produ??o de mudas, requerida uma lista das esp?cies produzidas, realizado o registro fotogr?fico do viveiro e marcadas suas coordenadas geogr?ficas. Observou-se que a nova legisla??o referente ?s sementes e mudas florestais criou exig?ncias para os produtores, visando garantir ao consumidor a identidade e a qualidade do que ? produzido. No entanto, algumas quest?es precisam ser revisadas e melhor formuladas visando diminuir a ?dist?ncia? existente entre a legisla??o e a realidade do produtor de sementes e mudas florestais. Os 70 viveiros est?o concentrados em alguns munic?pios e regi?es, n?o abrangendo o estado como um todo. Com rela??o ? estrutura administrativa, os viveiros do estado, s?o em maioria administrados por ?rg?os p?blicos, de pequeno porte e carecem de infraestrutura para produ??o de mudas. Apenas cinco entre os 70 viveiros est?o inscritos no RENASEM conforme exigido pela atual legisla??o. As mudas s?o produzidas com baixa diversidade de esp?cies, predomin?ncia de sacos pl?sticos como recipiente e pouco controle t?cnico e gerencial sobre a produ??o. Os dados demonstram que a atividade ainda tem muito a evoluir no estado, sendo necess?rias pol?ticas p?blicas visando fortalecer os viveiros j? existentes, estimular plantios de restaura??o da Mata Atl?ntica e consequentemente, a demanda por mudas florestais nativas
305

Tigmomorfogênese na rustificação e sobrevivência em mudas de Pinus taeda L. / Thigmomorphogenesis in the hardening and survival in Pinus taeda L. seedlings

Dranski, João Alexandre Lopes 04 March 2013 (has links)
Made available in DSpace on 2017-07-10T17:40:44Z (GMT). No. of bitstreams: 1 Joao_Alexandre_Lopes_Dranski.pdf: 1387311 bytes, checksum: e0d0c6141cd57f35175f1e8208b56884 (MD5) Previous issue date: 2013-03-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Thigmomorphogenesis is the adopted term to describe the growth response of plants to mechanical stimuli, naturally triggered by abiotic factors or artificially, by agroclimatic adverse event simulation. In the implantation of forest stands, such adversities limit of the seedlings establishment, and condition it to the recognize the limiting factor is the role in the hardening. It is speculated that the thigmomorphogenesis induced by stem bending become's more tolerant by forces exerted by the wind through the activation of mechanisms that alter the growth and accumulation of organic compounds. However, little is known if the employment of mechanical perturbations during seedlings hardening phase results in greater success in the implantation of forest stands. This present work aimed to evaluate morphophysiological alterations in Pinus taeda L. seedlings resulting from thigmomorphogenesis induced and its reflections about establishing in the field. For both, three experiments were conducted with the intention of quantify morphophysiological alterations resulting from stem bending and its reflections about establishing in the field; the partition and the buildup dry weight and carbon; and the correlation between lignin contente with field survival. P. taeda seedlings were produced by the nursery belonging to the company Sbaraini Agropecuária S.A., in Cascavel, PR. When reached the target size, were submitted to different intensities of stem bending during 60 days. At the end, were quantified morphophysiologic attributes, nutritionals, the dry weight and carbon partition between components, and lignin content. Additionally, the seedlings quality was measured by the root electrolyte leakage (REL). Posteriorly, part of the seedlings was planted in a commercial área of Pine monocropping in Cascavel, PR. Was quantitated by the survival, and increases of growth shoot at 90 and 360 days after planting. The increased intensity of the stem bendings reduced linearly of the stem height growth, the leaf area, resulting in the reduction in absolute growth rate and in the phosphorus content. Moderate intensities with up to 20 stem bending increased the secondary growth, the stem volume and the lignin content both in the root system how much aerial. The alteration in the primary and secondary growth was resulting of the carbon redistribution and of the dry weight accumulation in stem and in the root system, mostly in lateral roots, to the detriment of the leaf area reduction in terms of surface and dry matter. On the field, seedlings stimulated with that intensity showed higher survival and growth velocity, observed at 90 days after planting. After this period, he difference in growth velocity between seedlings stimulated or not has reduced, indicating acclimation of the seedlings unstimulated at the environment condition. There was correlation between the lignin content of the root system with the survival percentage at the 90 days, as well as the seedling quality measured by REL test proved to be predictive of field performance. Therefore, the application of 20 stem bendings applied during hardening of the P. taeda seedlings promoted greater success in implanting of the population in the experimental conditions analyzed. / Tigmomorfogênese é o termo adotado para descrever o crescimento dos vegetais em resposta ao estímulo mecânico, desencadeado naturalmente por fatores abióticos ou artificialmente, por simulação de eventos agroclimáticos adversos. Na implantação de povoamentos florestais, tais adversidades limitam o estabelecimento das mudas, e condicioná-las ao reconhecimento do fator limitante é o papel da rustificação. Especula-se que a tigmomorfogênese induzida por flexões caulinares tornam-as mais tolerantes às forças exercidas pelo vento, por meio da ativação de mecanismos que alteram o crescimento e o acúmulo de compostos orgânicos. Contudo, pouco se sabe se o emprego de perturbações mecânicas na fase de rustificação de mudas resulta em maior sucesso na implantação de povoamentos florestais. O presente trabalho objetivou avaliar as alterações morfofisiológicas em mudas de Pinus taeda L. resultantes da tigmomorfogênese induzida e seus reflexos sobre o estabelecimento no campo. Para tanto, três experimentos foram conduzidos com o intuito de: quantificar alterações morfofisiológicas resultantes de flexões caulinares e seus reflexos no desempenho das mudas a campo; a partição e o acúmulo de massa seca e carbono; e a correlação entre o teor de lignina com a sobrevivência no campo. Mudas de P. taeda foram produzidas pelo viveiro pertencente à empresa Sbaraini Agropecuária S.A., no município de Cascavel, PR. Quando atingiram altura maior que 15 cm, foram submetidas a diferentes intensidades de flexões caulinares durante 60 dias. Ao final, foram quantificados atributos morfofisiológicos, nutricionais, a partição de massa seca e carbono entre componentes da parte aérea (acículas, casca e cerne) e radicular (raízes laterais e pivotante), e o teor de lignina nas raízes e na parte aérea. Adicionalmente, a qualidade das mudas foi aferida pelo teste da perda eletrólitos de raízes (PER). Posteriormente, parte das mudas foi plantada em uma área comercial de monocultivo de Pinus em Cascavel, PR. Quantificou-se a sobrevivência, e os incrementos no crescimento aéreo aos 90 e 360 dias após o plantio. O aumento da intensidade de flexões caulinares reduziu linearmente o crescimento em altura, a área foliar, resultando em redução na taxa de crescimento absoluto e no teor de fósforo no sistema radicular e na parte aérea. Intensidades moderadas com até 20 flexões caulinares aumentou o crescimento secundário, o volume do caule e o teor de lignina tanto no sistema radicular quanto na parte aérea. A alteração no crescimento primário e secundário foi resultante da redistribuição de carbono e do acúmulo de massa seca no caule e no sistema radicular, principalmente em raízes laterais, em detrimento a redução de área foliar em termos de superfície e matéria seca. No campo, mudas estimuladas com 20 flexões caulinares externaram maior sobrevivência e velocidade de crescimento, observado aos 90 dias do plantio. Após este período, a diferença na velocidade de crescimento entre mudas estimuladas ou não reduziu, indicando aclimatação das mudas não estimuladas à condição do ambiente. Houve correlação entre o teor de lignina do sistema radicular com a porcentagem de sobrevivência aos 90 dias, assim como a qualidade da muda aferida pelo teste da PER mostrou ser preditivo ao desempenho no campo. Portanto, a aplicação de 20 flexões caulinares aplicadas na fase de rustificação de mudas de P. taeda promoveu maior sucesso na implantação do povoamento
306

Identifica??o, quantifica??o e inocula??o de fungos micorr?zicos arbusculares no sistema de produ??o de cana-de-a??car / Identification, quantification and inoculation of arbuscular mycorrhizal fungi in the sugarcane production system

FORS, Rosalba Ortega 18 February 2016 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2018-05-11T19:39:26Z No. of bitstreams: 1 2016 - Rosalba Ortega Fors.pdf: 2620047 bytes, checksum: d7b3d78fdeae080e9bee983dad584881 (MD5) / Made available in DSpace on 2018-05-11T19:39:26Z (GMT). No. of bitstreams: 1 2016 - Rosalba Ortega Fors.pdf: 2620047 bytes, checksum: d7b3d78fdeae080e9bee983dad584881 (MD5) Previous issue date: 2016-02-18 / CNPq / Brazil is the main sugarcane producer worldwide, with the crop accounting for 15% of the total fertilizers used in the country. In this context, the development and application of arbuscular mycorrhizal fungi (AMF) (Phylum Glomeromycota) inoculants represents a promising alternative for increasing the utilization eficiency of chemical fertilizers, mainly the phosphates In the present work a survey of the AMF community was carried out before planting and after harvesting of the "plant cane" in renewal (rotated or not with Brachiaria ruziziensis) and expansion (previously under pasture) areas. A similar assessment was carried out in sugarcane renovation and expansion areas where two experiments of inoculation with diazotrophic bacterias were being conducted. Under greenhouse conditions, two experiments for selecting AMF strains for sugarcane (Variety SP81-3250) in different soils and substrates were carried out. In renewal areas, after maintained sugarcane monocropping, a rotation cycle with B. ruziziensis between the ratoon removal and the new cane planting doesnot influence the AMF species richness. Prolonged monoculture of sugarcane tends to reduce the AMF diversity after the renewal of the sugarcane plantation, but stills quite high compared to other agricultural systems. In pasture areas converted to sugarcane plantation (expansion) the AMF species richness tends to be higher in the first year after the conversion (plant cane) compared to sugarcane renovation areas. The spore density reached the highest values after the "plant cane" harvesting. The AMF isolates with potentiality to compose a mycorrhizal inoculant for sugarcane areAcaulospora colombiana and Claroideoglomus etunicatum which favoured the development of the pre-sprouted seedlings of sugarcane in soil and substrate. Other isolates that promoted the sugarcane seedlings' development ou nutrition, but still need additional studies are Gigaspora margarita, Scutellospora calospora and Rhizophagus clarus. The expansion area soil (with moderate P content) was the most favorable for the sugarcane growth. The Multiplant substrate promoted the highest growth of the seedlings and favored the AMF colonization. The fertillization recommended for sugarcane seedling production inhibited the plants growth, particularly in the substrate Turfa F?rtil. The Sugar Mill substrate stimulated the seedlings growth the least. The rate of dark septate endophytes colonization (DSE) in the sugarcane seedlings of the cultivar SP81-3250 was high, independently of the inoculated AMF isolate. All the AMF isolates tested showed simultaneus colonization with DSE. / O Brasil ? o maior produtor mundial de cana-de-a??car, sendo a cultura respons?vel por 15% dos fertilizantes utilizados no pa?s. Nesse contexto, o desenvolvimento e aplica??o de inoculantes de fungos micorr?zicos arbusculares (FMAs) (Phylum Glomeromycota) representa uma promissora alternativa para incrementara efici?ncia de aproveitamento dos fertilizantes, principalmente os sfatados. No presente trabalho foi realizado um levantamento da comunidade de FMAs pr?-plantio e p?s-colheita da "cana planta" em ?reas de renova??o (rotacionadas ou n?o com Brachiaria ruzizensis) e expans?o (previamente sobre pastagem) do canavial. Uma avalia??o similar foi realizada em ?reas correspondentes a dois experimentos de inocula??o com bact?rias diazotr?ficas. Foram conduzidos, em casa de vegeta??o, dois experimentos de sele??o de linhagens de FMAs para cana-de-a??car (Cultivar SP81-3250) em diferentes solos e substratos. Em ?reas de monocultivo prolongado de cana-de-a??car uma rota??o com B. ruziziensis na ?poca da renova??o n?o influencia a riqueza da comunidade de FMAs. Por?m, a riqueza de FMAs diminui em monocultura prolongada de cana, mas ainda ? elevada comparada com outros sistemas agr?colas. A riqueza de FMAs em pastagem convertida a canavial ? maior na ?cana planta? comparada ? ?reas de renova??o de canavial. As maiores densidades de esporos nas ?reas canavieiras ocorrem ap?s a colheita da ?cana planta?. As linhagens de FMAs com potencialidade para compor um inoculante micorr?zico para cana-de-a??car s?o Acaulospora colombiana Claroideoglomus etunicatum as quais favorecem o desenvolvimento de mudas pr?-brotadas de cana tanto em solo como em substrato. Outras linhagens que precisam de estudos adicionais por promoverem crescimento ou nutri??o de mudas de cana s?o Gigaspora margarita, Scutellospora calospora e Rhizophagus clarus. O solo da ?rea de expans?o, com teores intermedi?rios de P, ? o mais favor?vel para o crescimento da cana-de-a??car. O substrato Multiplant foi o que mais estimulou o crescimento de mudas pr?-brotadas e promove a maior coloniza??o por FMAs. A aduba??o completa recomendada para a produ??o de mudas pr?-brotadas de cana-de-a??car inibiu o crescimento das plantas, particularmente no substrato Turfa F?rtil. O substrato da Usina promoveu o menor crescimento de mudas de cana-de-a??car. A taxa de coloniza??o radicular por DSE nas mudas da cultivar SP81-3250 foi elevada, independentemente da linhagem de FMA inoculada. Todas as linhagens de FMAs avaliadas apresentaram coloniza??o conjunta com DSE.
307

Avalia??o da toler?ncia ao alum?nio em pl?ntulas de maracujazeiro e mamoeiro. / Evaluation of aluminum tolerance in seedlings of Passion fruit and Carica papaya.

Silva, Aldir Carlos 06 March 2009 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2018-08-30T16:36:02Z No. of bitstreams: 1 2009 - Aldir Carlos Silva.pdf: 1230710 bytes, checksum: 56dbab398ff37045b73bd259ab1a15ac (MD5) / Made available in DSpace on 2018-08-30T16:36:02Z (GMT). No. of bitstreams: 1 2009 - Aldir Carlos Silva.pdf: 1230710 bytes, checksum: 56dbab398ff37045b73bd259ab1a15ac (MD5) Previous issue date: 2009-03-06 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / Aluminum tolerance studies in seedlings of Passion fruit (cvs. IAC-273/277, IACPaulista, IAC-275, FB-100) and Carica papaya (cvs.Taiung, Golden, Gran Golden, Baixinho de Santa Amalia) were performed in a growth chamber at the Laboratories of Chemistry of the Rhizosphere and Seeds of the Department of Fitotecnia, of University Federal Rural of Rio Janeiro, Institute of Agronomy. Experiments with different concentrations of Al were conducted in nutrient solution simple (with Ca) and complete, with the aims to analyze the tap root length, ratio of root lengths, relative root elongation, diameter of root and stem and effect of stains. Also were conducted experiments with seeds soaked in different concentration of Al to verify the percentage of germination, seedlings normal and abnormal. The use of simple nutrient solution was not satisfactory to shown the performance of seedlings of papaya. In passion fruit both nutrient solutions can be used in short term experiment. Over the concentration of 160?M of Al occurred effect of toxicity in root of seedlings of passion fruit and papaya, but at concentrations lower that 80?M there were stimulus of growth. The tap root length was the more efficient parameter to compare root toxicity. The soaking of seeds in the solution of aluminum did not affect the germination, root tap emission and the growth of seedlings until 1280?M. With the increased of time of contact with the Al solution, the young roots have been injured especially in papaya seedlings. The use of stains pyrocatechol violet and hematoxylin were both efficient to determinate the aluminum tolerance in papaya and passion fruit, but just pyrocatechol violet could compare the doses used, produced a color gradient with increasing concentration of aluminum. With the use of hematoxylin was only possible to separate the high concentrations of low concentrations of aluminum. The best passion fruit cultivar was IAC 273/277and papaya was Tainung / Os estudos da toler?ncia ao alum?nio em pl?ntulas de maracuj? (cvs. IAC-273/277, IACPaulista, IAC-275, FB-100) e mam?o (cvs.Tainug, Golden, Gran Golden, Baixinho de Santa Am?lia) foram realizados, em c?mara de crescimento nos Laborat?rios de Qu?mica da Rizosfera e Laborat?rio de Analise de Sementes, Departamento de Fitotecnia, Instituto de Agronomia da Universidade Federal Rural Rio de Janeiro. Foram realizados experimentos com diferentes concentra??es de alum?nio em solu??o nutritiva simples (com c?lcio) e completa, para analise do crescimento radicular utilizando os par?metros comprimento radicular, taxa de crescimento radicular, elonga??o radicular relativa, di?metro do colo, di?metro de ?pice da raiz principal bem como testes com corantes. Foi tamb?m realizado estudos do efeito da embebi??o das sementes com solu??es de alum?nio para verificar o efeito na porcentagem de germina??o, pl?ntulas normais e anormais, e n?o germinadas. O uso da solu??o nutritiva simples para realizar testes de curta dura??o de contacto ao alum?nio, n?o foi satisfat?rio para mam?o, sendo mais adequado o uso de solu??o nutritiva completa. Em maracuj?, ambas as solu??es podem ser utilizadas. As pl?ntulas de maracuj? crescidas em solu??o simples com o aumento do tempo de contacto com alum?nio na solu??o, as ra?zes ficaram endurecidas. Em concentra??es acima de 160?M de alum?nio, ocorreu efeito fitotoxico, contudo em concentra??es menores que 80?M ocorreu at? aumento do crescimento radicular para mam?o e maracuj?. O comprimento radicular foi o mais eficiente par?metro indicador da toler?ncia ao alum?nio. A embebi??o das sementes em alum?nio n?o afetou a germina??o a emiss?o da raiz principal e o crescimento da pl?ntula at? a concentra??o da solu??o de embebi??o de 1280?M, mas a medida que aumentou o tempo de contato e a concentra??o de alum?nio, as ra?zes rec?m emitidas sofreram danos, principalmente as de pl?ntulas de mam?o. O uso dos corantes qu?micos violeta de pirocatecol e hematoxilina foram eficiente na determina??o da toler?ncia ao alum?nio em maracuj? e mam?o, mais somente o violeta de pirocatecol permitiu comparar as doses entre si, gerando um gradiente de colora??o com o aumento da concentra??o de alum?nio, com o uso da hematoxilina s? foi poss?vel separar as concentra??es altas das concentra??es baixas de alum?nio. As melhores cultivares nas condi??es testadas foi a IAC 273/277 de maracuj? e a cv Tainung de mam?o
308

NR Primjena biostimulatora u proizvodnji begonije (Begonia semperflorens Link.et Otto) i kadifice (Tagetes patula L.) / Biostimulants application in production begonia (Begonia semperflorens Link et. Otto) and marigold (Tagetes patula L.)

Zeljković Svjetlana 29 November 2013 (has links)
<p>U ovom istraživanju je utvrđen uticaj primjene biostimulatora na morfolo&scaron;ke i fiziolo&scaron;ke parametre rasta i razvoja, te na mineralni sastav kod sezonskog cvijeća, kadifice i stalnocvjetajuće begonije.&nbsp; Uticaj biostimulatora je ispitan kroz tri godine istraživanja u za&scaron;tićenom prostoru i na otvorenom polju. Istraživanje je provedeno na mladim biljkama-rasadu prije presađivanja i na odraslim biljkama. U fazi rasada primjenjen je biostimulator Radifarm, a u fazi odraslih biljaka primjenjeni su biostimulatori Megafol, Kendal i Viva.&nbsp; Tretman sa primjenjenim biostimulatorima, u sve tri godine istraživanja i oba načina uzgoja, je značajno uticao na povećanje svježe i suhe mase korijena i nadzemnog dijela ispitivanih cvjetnih vrsta. Takođe, svi praćeni morfolo&scaron;ki parametri rasta i razvoja bili su pod pozitivnim uticajem tretmana biostimulatorima. Kod rasada kadifice i stalnocvjetajuće begonije, tretman Radifarmom je snizio sadržaj prolina u listovima te se i na taj način potvrdio pozitivan uticaj biostimulatora na smanjenje abiotskog stresa. Svi primjenjeni biostimulatori su značajno ubrzali cvjetanje i produžili vrijeme cvatnje u poređenju sa kontrolnim biljkama. Tretmani biostimulatorima su uticali na povećanje ukupnog sadržaja svih elemenata ishrane u cijelim biljkama kadifice i stalnocvjetajuće begonije. Rezultati pokazuju korist primjene biostimulatora u uzgoju sezonskog cvijeća u fazi rasada, ali i u fazi uzgoja na otvorenom polju, jer pozitivno utiču na procese rasta i razvoja kroz ublažavanje abiotskog stresa uzrokovanog presađivanjem. Na kraju, javlja se potreba za daljim istraživanjem mogućnosti primjene biostimulatora i na druge poljoprivredne kulture, kao preporučljive tehnolo&scaron;ke mjere za&scaron;tite životne sredine, jer primjenom biostimulatora ne dolazi do ispiranja azotnih materija u dublje slojeve zemlji&scaron;ta.</p> / <p>This research showed the effect of biostimulant application on morphophysiological growth and development indicators and plant mineral content of seasonal flowers, marigold and begonia.&nbsp; Biostimulant effect was investigated in three years, where plants were grown in greenhouse and in open field. Young seasonal plants before transplanting and adult plants after transplanting in open field were analysed to determine the influence of biostimulant application. Biostimulant Radifarm was applied before transplanting, and Megafol, Kendal and Viva after transplanting.&nbsp; Treatment with applied biostimulants, in three years of investigation and both growing conditions, significantly increased root and stem fresh and dry weight of seasonal flowers. Also, all morphological properties were under positive influence of biostimulants treatment. Furthermore, treatment with biostimulant Radifarm resulted by lower proline content in leaves, which confirmed positive effect biostimulant on abiotical stress conditions. All applied biostimulants, significantly increased earlier flowering and ensured longest flowering in marigold and begonia. The most significant influence of biostimulants application in role of plant nutrition was increased mineral nutrients total content in the whole plant in both sampling.&nbsp; Results showed advantage of biostimulants application in seasonal flowers seedlings production, but also after transplanting in open filed, because their application intensified growth process through damage reduction caused by abiotic stress during transplanting. At the end, there is a need for further investigation of biostimulant function, their application possibilities on others agricultural plants and their combinations in modern agriculture towards environmental friendly production strategy.</p>
309

Controle de gramíneas exóticas invasoras em área de restauração ecológica com plantio total, floresta estacional semidecidual, Itu-SP / Control of Urochloa decumbens Stapf. in ecological restoration area by planting in total area, Semideciduous Forest, Itu SP.

Martins, Adriana Ferrer 10 March 2011 (has links)
A atividade de restauração florestal é freqüentemente realizada em áreas degradadas, ocupadas por gramíneas exóticas invasoras, e o controle destas plantas é fator determinante no sucesso da restauração. Esta pesquisa tem o objetivo de testar intervenções para controle da gramínea exótica invasora Urochloa decumbens Stapf. em área de restauração florestal, com plantio de mudas nativas em área total. O delineamento utilizado foi o de blocos com parcelas subdivididas. Os tratamentos aplicados nas parcelas foram: 1. Não inversão de solo (R) e 2. Com inversão de solo por gradagem (G). Os tratamentos aplicados nas subparcelas foram: 1. Aplicação de herbicida na instalação e nas manutenções (H), 2. Plantio de feijão de porco (Canavalia ensiformes DC.) com aplicação de herbicida na instalação e nas manutenções só roçagem (H+FP), 3. Plantio de feijão de guandu (Cajanus cajan L.) com aplicação de herbicida na instalação e nas manutenções só roçagem (H+FG), 4. Plantio de feijão de porco (Canavalia ensiformes DC.) na instalação e nas manutenções só roçagem (FP), 5. Plantio de feijão de guandu (Cajanus cajan L.) na instalação e nas manutenções só roçagem (FG), 6. Roçagem na instalação e nas manutenções (sem aplicação de herbicida e sem plantio de adubos verdes) (s/Hs/AV). O desenvolvimento da gramínea foi avaliado pela altura e porcentagem de cobertura no solo e o desenvolvimento das mudas pela altura, área de copas e mortalidade. As analises estatísticas foram realizadas pelo pacote estatístico SAS. O experimento permitiu concluir que, no período entre plantio e a primeira manutenção (realizada 3 meses após o plantio) as coberturas vivas na interação R(H+FP) e R(H+FG) diminuíram a porcentagem de cobertura no solo de U. decumbens em relação ao tratamento R(s/Hs/AV) e os tratamentos (H+FP) e (H+FG) diminuíram a altura da U. decumbens no primeiro mês em relação ao tratamento (s/Hs/AV). Após a primeira manutenção, apenas o tratamento (H) diminuiu a porcentagem de cobertura no solo de U. decumbens e a altura desta gramínea em relação a todos os demais. Nas variáveis referentes ao desenvolvimento das mudas, apenas a variável área de copas apresentou diferença significativa nas interações entre os tratamentos R(H) e R(s/Hs/AV) 7 meses após o plantio e R(H) em relação a todos os demais 9 meses após o plantio, sendo que o R(H) apresentou maior área de copas. Neste experimento, o uso de adubos verdes em área de restauração florestal não melhorou o desenvolvimento das mudas plantadas. O tratamento que promoveu menor porcentagem de cobertura no solo de U. decumbens, menor altura de Urochloa decumbens Stapf. e mudas com maior área de copas foi o que teve aplicação de herbicida na instalação e nas manutenções (H). / The activity of forest restoration is often performed in areas covered by exotic grasses. In this way, the weed control of these plants is a determining factor in the success of restoration. This project aims to test different interventions for Urochloa decumbens Stapf. control in an area of forest restoration with seedlings planting in total area. The design adopted was split plot treatments divided in blocks, with each plot with different kind of soil tillage systems: 1. tillage (no soil movement) and 2. Harrowing (ground motion); and subplots with: 1. herbicide application in the installation and during maintenance (H); 2. herbicide application and planting of bean (Canavalia ensiformis DC.) in the installation and maintenance on mowing (FP + H); 3. herbicide application and planting beans (Cajanus cajan L.) in the installation and maintenance on mowing (H + FG); 4. planting bean (Canavalia ensiformis DC.) in the installation and maintenance on mowing (FP), 5. planting bean (Cajanus cajan L.) in the installation and maintenance on mowing (FG); and 6. no herbicide application nor planting green manure in the installation and the maintenance on mowing (s / Hs / AV). The grass height and percentage of occupation in of the soil was measured, as well the height, canopy area and mortality of seedlings, all of them analyzed by the SAS statistical package. In the period between planting and first maintenance (3 months), the living roofs in the interaction R (H + FP) and R (H + FG) controlled the percentage of invasive exotic grasses in the soil, and the treatments (H + FP) and ( H + FG) controlled the height of grasses in the first month. After the first maintenance, only the treatment (H) controlled the grasses in percentage of occupancy in the soil and height. Regarding the variables referred to the seedlings, only the canopy area showed a significant difference between treatments (H) and (s / Hs / AV) 7 months after planting and the (H) treatment showed a difference among all others, 9 months after planting,, as well its showed the biggest area. In this experiment the use of green manure in the area of forest restoration did not improve seedling growth. The (H) treatment was the one that promotes the Urochloa decumbens Stapf. control for a longer time and the seedlings with the largest canopy area.
310

Functional assessment of the role of cyclic nucleotide-gates channel (CNGC10) and salt overly sensitive (SOS1) antiporter in salinity tolerance in Arabidopsis

Guo, Kunmei January 2009 (has links)
Control of intracellular ion homeostasis is pivotal to plant salt tolerance. Plants have developed a number of mechanisms to keep ions at appropriate concentrations. Both transporters and channels on the plasma membrane play important roles in this function. Plant cyclic nucleotide-gated channels (CNGCs) in the plasma membrane are non-selective monovalent and divalent cation channels. So far, most studies on plant CNGCs have been conducted on heterologous systems. In planta, reverse genetic studies revealed the role of different CNGCs in cation uptake, transport and homeostasis. However, there is little information available about the functional characteristics of plant CNGCs. Among the 20 members of this protein family in Arabidopsis, only AtCNGC2 has been functionally identified as an ion channel; therefore, more functional characterization needs to be done on other members of this protein family. Several CNGCs were suggested to be involved in K+, Ca2+ and Na+ uptake and transport, but available information is scarce. This study investigated the relationship between CNGC10 and ion transport in Arabidopsis, with a particular emphasis on the involvement of CNGC10 in salt tolerance. Arabidopsis thaliana wild type (WT) and two AtCNGC10 antisense lines (A2 and A3) were used to characterise the impact of different level of salt stress on (i) root growth, ion concentration in tissues, ion fluxes across the root surface and intracellular ion concentration and pH at the seedling stage, and (ii) photosynthesis and ion concentration in tissues at the flowering stage. Plants of both antisense lines had higher K+ and lower Ca2+ and Mg2+ concentrations in shoots than WT plants when grown in non-salt control 1/4 Hoagland solution. Altered K+, Ca2+ and Mg2+ internal concentrations in AtCNGC10 antisense lines compared with WT plants under non-salt conditions indicated disturbed long distance ion transport, especially xylem loading/retrieval and/or phloem loading. The results of ion fluxes across the root surface also suggested that AtCNGC10 might be involved in transport of K+, Ca2+ and Mg2+ in tissue. Under sudden salt exposure, higher Na+ efflux and smaller K+ efflux in both antisense lines suggested that AtCNGC10 channels are involved in Na+ and K+ transport. The shoots of AtCNGC10 antisense lines A2 and A3 contained higher Na+ concentrations and significantly higher Na+/K+ ratios compared to WT, resulting in impaired photosynthesis and increased salt sensitivity in A2 and A3 than in WT plants. In contrast, seedlings of both antisense lines exposed to salt stress had lower shoot Na+/K+ ratios and longer roots than WT seedlings, indicating that A2 and A3 were more salt-tolerant than WT in the seedling stage, likely because growth is less dependent on photosynthesis in the seedling than in the flowering stage. These results suggested CNGC gene might play a different role during different developmental stages and in various plant organs.

Page generated in 0.0933 seconds