Dynamics of roots of arboreal species: vision of the literature

A din\ue2mica do sistema radicular de uma planta \ue9 de extrema import\ue2ncia para defini\ue7\uf5es de t\ue9cnicas de manejo nas \ue1reas agr\uedcola e florestal. A raiz, al\ue9m de ter a fun\ue7\ue3o b\ue1sica de sustentar a planta, \ue9 o meio de esta absorver \ue1gua e nutrientes. Observando a import\ue2ncia do sistema radicular de uma planta e a escassez de estudos sobre o assunto, esta revis\ue3o tem como objetivo levantar os pontos abordados por pesquisadores da \ue1rea florestal, com rela\ue7\ue3o aos fatores ambientais que influenciam a produ\ue7\ue3o de ra\uedzes finas, aos recursos dispon\uedveis no solo, \ue0s varia\ue7\uf5es na longevidade das ra\uedzes e nos processos de senesc\ueancia e substitui\ue7\ue3o das ra\uedzes finas. A din\ue2mica observada na rizosfera \ue9 sens\uedvel \ue0s varia\ue7\uf5es edafoclim\ue1ticas, sendo que esse comportamento varia ainda em fun\ue7\ue3o das esp\ue9cies, idade do povoamento, competi\ue7\ue3o entre indiv\uedduos, recursos dispon\uedveis, manejo, profundidade de avalia\ue7\ue3o, competi\ue7\ue3o entre esp\ue9cies, entre outros.The root system dynamics of a plant are very important for definitions of management in the agricultural and forest area. The root, besides the basic function of sustaining the plant, is the part through which plants absorb water and nutritious. In function of the importance of the root system of a plant and the shortage of studies on this subject, this revision has as objective to approach the researched themes in the forest area, regarding the environmental factors that influence the fine roots production, the available resources in the soil, the variations in the roots longevity and the aging processes and turnover of the fine roots. The root dynamics are sensitive to the climate and soil variations, and still variable in function of the species, age of the forest or plantation, competition among individuals, resources available, management, evaluation depth, competition among species, and others

Effect of the roots pruning in the growth of the Eucalyptus seedlings

O trabalho teve como objetivo avaliar o efeito das podas no sistema radicial de mudas de Eucalyptus camaldulensis , produzidas em blocos. No viveiro, foram testados tr\ueas tratamentos (T1: sem poda do sistema radicial; T2: 1 poda do sistema radicial; T3: duas podas do sistema radicial), disposto em DIC, com nove repeti\ue7\uf5es, sendo cada repeti\ue7\ue3o composta por 96 mudas. Parte dessas mudas foi levada para o campo para avalia\ue7\ue3o do efeito da poda das ra\uedzes ap\uf3s o plantio no campo. Foram dispostas em quatro blocos casualizados, com 49 mudas por parcela. O substrato utilizado para produ\ue7\ue3o de mudas foi a mistura de plantmax florestal (60%) e fibra de coco de granulometria mista (40%), sendo adicionados 8 g de osmocote (19-06-10) por quilo do substrato. As podas das ra\uedzes na fase de viveiro foram realizadas aos 80 e 90 dias ap\uf3s a semeadura, com auxilio de uma l\ue2mina afiada. As mudas foram avaliadas aos 100 dias ap\uf3s a semeadura, quanto \ue0 altura da parte a\ue9rea, di\ue2metro do colo, massa seca da parte a\ue9rea, comprimento e di\ue2metro das ra\uedzes. No campo as mudas foram avaliadas quanto a altura e di\ue2metro ao 1, 3, 5, 7 e 9 meses ap\uf3s plantio. No viveiro, mesmo n\ue3o havendo diferen\ue7a no crescimento em altura e di\ue2metro da parte a\ue9rea das mudas entre os tratamentos, aquelas que n\ue3o sofreram poda de suas ra\uedzes (T1) apresentaram menor produ\ue7\ue3o de massa seca da parte a\ue9rea, representada pelas folhas. J\ue1 para o sistema radicial, quando foram aplicadas duas podas durante o ciclo de produ\ue7\ue3o, as mudas apresentaram maior comprimento e di\ue2metro de ra\uedzes produzidas. N\ue3o houve diferen\ue7a no crescimento das mudas ap\uf3s plantio no campo, no entanto, a condi\ue7\ue3o clim\ue1tica na \ue9poca de implanta\ue7\ue3o e condu\ue7\ue3o do experimento, al\ue9m do s\uedtio favor\ue1vel ao desenvolvimento das mudas pode ter contribu\ueddo para esse resultado, sendo necess\ue1ria condu\ue7\ue3o de novo experimento, para avaliar o efeito das podas, em mudas plantadas em condi\ue7\uf5es adversas.The objective of this work was to evaluate the effect of the roots prunings of Eucalyptus camaldulensis seedlings produced in blocks. In the nursery, three treatments were tested (T1: without roots pruning; T2: one roots pruning; T3: two roots pruning), in Completely Randomized Design, with nine replicates (96 seedlings for replicate). Portion of those seedlings was taken for the field for evaluation of the pruning roots effect after the planting in the field. The substrate used for production of seedlings was the mixture of forest plantimax (60%) and fiber of the coconut (40%), 8g of osmocote were added (19-06-10) per kilo of the substrate. The prunings of the roots in the nursery were accomplished to the 80 and 90 days after sowing, with sharp sheet. The seedlings were evaluated 100 days after the sowing, for height, stem diameter, shoot dry matter, length and diameter roots. In the field the seedlings were evaluated as the height and diameter to the 1, 3, 5, 7 and 9 months after planting. In the nursery, there was no difference in the shoot height and diameter of the seedlings among the treatments, but the seedlings which did not receive any root pruning (T1) presented smaller production of shoot dry matter, acted by the leaves. When two prunings were applied during the production cycle, the seedlings presented larger length and diameter roots. There was not nay difference in the growth of the seedlings after planting in the field; however, the climatic condition in the implantation and conduction of experiment, besides the favorable site to the development of the seedlings might have contributed to that result, being necessary the conduction again experiment, to evaluate the effect of the prunings, in seedlings planted in adverse conditions

Physiological Characteristics Of Eucalyptus spp Seedlings Submitted To Saline Stress

The objective of this study was to evaluate the effects of increasing sodium chloride (NaCl) concentrations on quantum potential efficiency of the photosystem II (Fv/Fm), index of the intensity of the green color in leaves (SPAD value), dry leaf biomass, leaf area and potassium (K) and sodium (Na) concentrations in Eucalyptus seedlings leaves. The experiment was carried out in a green house, using 11.5 L pots filled with sand and irrigated with nutrient solution, in Campos dos Goytacazes (RJ). The experiment was set up according to a completely randomized factorial design, with four species ( Eucalyptus camaldulensis , Eucalyptus tereticornis , Eucalyptus pellita and Eucalyptus robusta ) and five saline levels (1.41; 2.50; 4.50; 6.45 and 8.33 dS m-1), with five replicates. Up to the maximum applied saline level, seedlings of Eucalyptus camaldulensis , Eucalyptus tereticornis and Eucalyptus robusta showed positive responses regarding SPAD values and quantum potential efficiency of the photosystem II, dry leaf biomass and leaf area. These evaluations suggest tolerance of these species to saline conditions. Seedlings of Eucalyptus pellita showed sensitivity to saline stress. The reductions of dry leaf biomass and leaf area may be related to seedling resistance to saline conditions.Este trabalho objetivou avaliar como o aumento da concentra\ue7\ue3o de cloreto de s\uf3dio (NaCl) influencia o rendimento qu\ue2ntico potencial do fotossistema II (Fv/Fm), \uedndice da intensidade da cor verde nas folhas (valor SPAD), \ue1rea foliar, biomassa seca foliar e concentra\ue7\ue3o de pot\ue1ssio (K) e s\uf3dio (Na) nas folhas de mudas de esp\ue9cies de Eucalyptus. O experimento foi conduzido em casa de vegeta\ue7\ue3o, em vasos de 11,5 L, preenchidos com areia e irrigados com solu\ue7\ue3o salinizada, em Campos dos Goytacazes, RJ. O delineamento experimental foi inteiramente casualizado em esquema fatorial com quatro esp\ue9cies ( Eucalyptus camaldulensis , Eucalyptus tereticornis , Eucalyptus pellita e Eucalyptus robusta ) e cinco n\uedveis de salinidade (1,4; 2,50; 4,50; 6,45 e 8,33 dS m-1), com cinco repeti\ue7\uf5es. At\ue9 o n\uedvel m\ue1ximo de salinidade aplicado, as mudas de Eucalyptus camaldulensis , Eucalyptus tereticornis e Eucalyptus robusta responderam positivamente com rela\ue7\ue3o \ue0s caracter\uedsticas valor SPAD, rendimento qu\ue2ntico potencial do fotossistema II, biomassa seca foliar e \ue1rea foliar. Essas avalia\ue7\uf5es sugerem toler\ue2ncia dessas esp\ue9cies \ue0s condi\ue7\uf5es de salinidade impostas. Mudas de Eucalyptus pellita mostraram sensibilidade ao estresse salino. As redu\ue7\uf5es da biomassa seca e \ue1rea foliar podem estar relacionadas a estrat\ue9gias de resist\ueancia das plantas ao estresse salino

ROOT HYDRAULIC CONDUCTIVITY AND PHOTOSYNTHETIC CAPACITY OF EUCALYPT CLONAL CUTTINGS WITH ROOT MALFORMATION INDUCTIONS

A redu\ue7\ue3o do ganho em biomassa de lenho em \ue1rvores tem sido atribu\uedda \ue0 ocorr\ueancia de deforma\ue7\uf5es radiculares ainda na fase de viveiro. O objetivo deste trabalho foi avaliar a condutividade hidr\ue1ulica do sistema radicular, trocas gasosas e a efici\ueancia fotoqu\uedmica de mudas clonais de eucalipto com e sem indu\ue7\ue3o de deforma\ue7\uf5es radiculares. Os tratamentos foram: 1 \u2013 mudas sem a indu\ue7\ue3o de deforma\ue7\uf5es radiculares (produzidas de acordo com metodologia operacional do viveiro da Fibria Celulose S.A.) e 2 \u2013 mudas com indu\ue7\ue3o de deforma\ue7\uf5es radiculares. A indu\ue7\ue3o da deforma\ue7\ue3o radicular n\ue3o resultou em queda no volume radicular. Contudo, deforma\ue7\uf5es radiculares provocaram redu\ue7\ue3o na condutividade hidr\ue1ulica do sistema radicular, assim como foram verificadas quedas na taxa fotossint\ue9tica das mudas ao longo do dia. A queda da taxa fotossint\ue9tica em mudas com indu\ue7\ue3o de deforma\ue7\uf5es radiculares est\ue1 associada a fatores estom\ue1ticos e n\ue3o estom\ue1ticos.The gain reduction of wood biomass in trees has been assigned to root deformations even in the nursery phase. The objective of this work was the evaluation of the root system hydraulic conductivity, gas exchanges and photochemical efficiency of eucalypt clonal cuttings with and without root deformation inductions. The treatments were: 1) operational cuttings without root malformation inductions (grown according to the used methodology of Fibria Cellulose S.A.); 2) root deformation inductions. These inductions did not promote decrease in the root volume. However, the deformations brought reduction of the root system hydraulic conductivity. Lower photosynthetic rates were also observed along the day in the cuttings in the root deformed cuttings. This decreasing rate is connected to stomatal and non stomatal factors

ENRAIZAMENTO DE MINIESTACAS E PRODUTIVIDADE DE MINICEPAS DE CEDRO AUSTRALIANO MANEJADAS EM CANALET 5ES E TUBETES

The planted forest stands aim to supply the growing demand for wood, especially for the sawing and veneer industries, that exclusively used wood from native forests. The Australian cedar ( Toona ciliata ) belongs to the family Meliaceae, is the species of interest for this sector. Studies with the Australian cedar propagation have carried out in latest years, mainly involving the use of mini-cuttings due to the need for high quality cuttings. The objectives of this paper were to evaluate the rooting and the productive capacity of Australian cedar mini-strains, managed in lifted seedbeds and 180 cm3 plastic tubes systems. So, two mini-clone gardens were set up. The mini-strains of both gardens were grown from cut-off seedlings originated from seeds. Successive collections of sprouts were carried out to get the mini-cuttings. Afterwards, they remained in the rooting area under intermittent mist. Thirty days later the rooting characteristics of the cuttings originated from both mini-gardens were evaluated. The period of permanence of the cuttings in the gardens was seven-month long. During this period, six collections from the lifted seedbed and four from the plastic tubes were carried out. The mini-strains in the two systems showed 100 % of survival rate. At the end of this seven-month period, an increasing tendency of the average number of mini-cutting was found out in both systems. Those from the lifted seedbed showed more productivity than those ones from the tubes. The plants from the mini-cuttings of the tube showed higher number and length of adventitious roots at the end rooting stage.Os povoamentos florestais plantados buscam atender \ue0 demanda crescente por madeira, principalmente, para as ind\ufastrias de serraria e de lamina\ue7\ue3o, que utilizavam madeira exclusivamente de matas nativas. O cedro australiano ( Toona ciliata ), pertencente \ue0 fam\uedlia Meliaceae, \ue9 uma das esp\ue9cies de interesse desse setor. Pela necessidade cada vez maior por mudas de alta qualidade, estudos sobre propaga\ue7\ue3o de cedro australiano t\ueam sido realizados nos \ufaltimos anos, principalmente envolvendo o uso da miniestaquia. Os objetivos deste trabalho foram avaliar o enraizamento e a capacidade produtiva das minicepas de cedro australiano, manejadas em sistemas de canalet\uf5es e em tubetes de 180 cm3. Assim, estabeleceram-se dois minijardins de minicepas formadas a partir de mudas recepadas, produzidas por sementes. Nestes dois sistemas, foram realizadas coletas sucessivas de brota\ue7\uf5es para confec\ue7\ue3o de miniestacas, que permaneceram por 30 dias no setor de enraizamento, em c\ue2mara com nebuliza\ue7\ue3o intermitente. Ap\uf3s este per\uedodo, foram avaliadas as caracter\uedsticas do enraizamento das mudas originadas nos dois sistemas de minijardins testados, que foram conduzidos por sete meses e, durante este per\uedodo, foram realizadas seis coletas no minijardim de canalet\ue3o e quatro, no de tubetes. As minicepas dos dois sistemas apresentam 100 % de sobreviv\ueancia. Ao final do per\uedodo observou-se tend\ueancia no aumento do n\ufamero m\ue9dio de miniestacas em ambos os sistemas. As minicepas do sistema de minijardim em canalet\ue3o s\ue3o mais produtivas que as do sistema conduzido em tubetes. As mudas originadas de miniestacas do sistema de tubetes apresentam maior n\ufamero e comprimento de ra\uedzes advent\uedcias na expedi\ue7\ue3o do setor de enraizamento

PRODUTIVIDADE DE MINICEPAS DE CEDRO AUSTRALIANO E REMO\uc7\uc3O DE NUTRIENTES PELA COLETA SUCESSIVA DE MINIESTACAS

The management of ministumps to produce minicuttings results in the continuous removal of nutrients and it is necessary replacement to avoid depletion and decline in production. Thus, it is necessary to determine the amount of nutrients removed over time, in different management models, to enable commercial mulproduction. The objective of this study was to evaluate two minigarden multiclonal systems of Toona ciliata , in plastic tubes and bed, for productivity and nutrients removal over time by ministumps, produced by seeds, submitted to successive collections of minicuttings. One hundred and eighty-six seedlings were used in each management system. In this paper, it was determined the nutrient content in shoots issued by 20 ministumps randomly selected in each system. Five shoots were collected at intervals of 32 days in bed system, while in the plastic tubes system three shoots were collected at intervals of 31 days. The data were analyzed by a sample simple random considering an infinite population of minicuttings. The qualitative treatment average was compared by confidence interval using the Student t test, 5% probability, and the quantitative treatment (productivity and nutrients removed in time by ministumps) by regression. It has been found that the productivity and nutrient contents removed by ministumps in bed were higher than in the plastic tubes. Nitrogen and potassium are the nutrients most removed by ministumps in both systems. Here, it was presented the curves corresponding to the nutrients exported, to estimate the replacement that will be made in each system over time.O manejo de minicepas para produ\ue7\ue3o de miniestacas resulta na remo\ue7\ue3o cont\uednua de nutrientes, sendo indispens\ue1vel sua reposi\ue7\ue3o para evitar o esgotamento e queda na produ\ue7\ue3o. Assim, \ue9 necess\ue1rio determinar a quantidade de nutrientes removidos no tempo, em diferentes modelos de manejo, para viabilizar a produ\ue7\ue3o comercial. O objetivo deste trabalho foi avaliar dois sistemas de minijardim multiclonal de Toona ciliata , conduzidos em tubete e canalet\ue3o, quanto \ue0 produtividade e remo\ue7\ue3o de nutrientes ao longo do tempo pelas minicepas, produzidas por via seminal, submetidas a coletas sucessivas de miniestacas. Foram utilizadas 186 mudas em cada sistema de manejo. Foram determinados os conte\ufados de nutrientes nas brota\ue7\uf5es emitidas por 20 minicepas selecionadas ao acaso em cada sistema. Foram realizadas cinco coletas de brota\ue7\uf5es em intervalos m\ue9dios de 32 dias no sistema canalet\ue3o, enquanto no sistema tubete foram realizadas tr\ueas coletas de brota\ue7\uf5es em intervalos m\ue9dios de 31 dias. Os dados foram analisados por amostragem simples ao acaso considerando uma popula\ue7\ue3o infinita de miniestacas. As m\ue9dias dos tratamentos qualitativos foram comparadas por intervalo de confian\ue7a, utilizando o teste \u201ct\u201d de Student, a 5% de probabilidade, e os tratamentos quantitativos (produtividade e nutrientes removidos no tempo pelas minicepas) por regress\ue3o. Foi constatado que a produtividade e o conte\ufado de nutrientes removidos pelas minicepas manejadas em canalet\ue3o foram superiores \ue0 dos tubetes. O nitrog\ueanio e o pot\ue1ssio foram os nutrientes mais removidos pelas minicepas em ambos os sistemas de manejo. S\ue3o apresentadas as equa\ue7\uf5es que descrevem as quantidades removidas ao longo do tempo nos dois sistemas

INFLU\ucaNCIA DA POSI\uc7\uc3O DAS MINIESTACAS NA QUALIDADE DE MUDAS DE CEDRO AUSTRALIANO E NO SEU DESEMPENHO INICIAL NO P 3S-PLANTIO

The Toona ciliata (Australian cedar), originated from Australia showed high acclimatization in Brazil, where it found appropriate conditions for its growth, particularly in southern Bahia and throughout the southeastern region. However, the plantings presented irregular stems. Besides the seeds are a limiting resource, in result of their production seasonality and short viability period. This study aimed the evaluation of the quality of cuttings grown from 6 cm length apical, middle and basal mini-cutting positions of the sprouts of the mini-strains - from seminal origin - and the initial growth of cuttings. It was established a multi-clone mini-garden containing a total of 284 mini-strains. After cutting off the sprouts of the seedlings - to originate the mini-strains - the mini-cuttings from the above different positions were collected. At the lifting time of the rooting sector, dry mass weight of shoot and root, length, diameter, number of adventitious roots and survival data were collected. The height and diameter were monitored fortnightly, starting from 80 days after the staking of the mini-cuttings. At the end of the production cycle, the dry mass weight of shoot, the root number, the diameter and the length of root cuttings were evaluated. Thirty percent of the cuttings were transplanted to pots of 3.8 L, in the open air where the height and basal diameter, the dry mass of shoot, the leaves and the roots were measured 60 days after the transplanting. Cuttings originated from the basal mini-cuttings at the end of the lifting time of the rooting sector, showed the highest height and diameter, however no difference was pointed out regarding to the basal diameter of cuttings originated from the middle position. There were no differences related to the shoot dry mass and the adventitious root number, the dry mass weight, the total length and the diameter of the adventitious roots of cuttings in relation to the mini-cutting positions in the sprouts. The survival was high, averaging 94.7 % for the apical, 96.3 % for the middle and 96.6 for basal position. Sixty days after transplanting, despite the differences in the diameter and the height of the cuttings at the end of the nursery phase, no difference in the height, the diameter and the dry mass weight of shoots, the leaves and the roots as pointed out in the treatments.O cedro australiano, origin\ue1rio da Austr\ue1lia, adaptou-se muito bem no Brasil, que apresenta condi\ue7\uf5es adequadas para o seu desenvolvimento, sobretudo no sul da Bahia e em toda a regi\ue3o sudeste. Por\ue9m, os plantios s\ue3o irregulares e as sementes s\ue3o insumo limitante, por sua sazonalidade de oferta e curta viabilidade. A finalidade deste estudo foi avaliar a qualidade das mudas obtidas de miniestacas apicais, intermedi\ue1rias e basais com 6 cm de comprimento oriundas de brotos de minicepas de Toona ciliata cultivadas em minijardim multiclonal em canalet\uf5es e o crescimento inicial das mudas no p\uf3s-plantio. Foi implantado um minijardim multiclonal em canalet\uf5es, contendo um total de 284 minicepas. A partir da parte a\ue9rea das mudas recepadas para forma\ue7\ue3o das minicepas, foram produzidas miniestacas de diferentes posi\ue7\uf5es. Na expedi\ue7\ue3o do setor de enraizamento foram coletados dados de massa seca da parte a\ue9rea e do sistema radicular, comprimento, di\ue2metro, n\ufamero de ra\uedzes advent\uedcias e sobreviv\ueancia. A altura e di\ue2metro das mudas foram monitorados quinzenalmente, a partir de 80 dias, ap\uf3s o estaqueamento. Ao final do ciclo de produ\ue7\ue3o, as mudas foram avaliadas com rela\ue7\ue3o \ue0 massa seca da parte a\ue9rea e do sistema radicular, n\ufamero, di\ue2metro e comprimento das ra\uedzes. Para avaliar as mudas ap\uf3s o plantio, 30 % das mudas foram transferidas para vasos de 3,8 L, onde foram avaliadas em altura e di\ue2metro do colo e, aos 60 dias, em massa seca do caule, folhas e ra\uedzes. As mudas provenientes das miniestacas basais, na expedi\ue7\ue3o da fase de enraizamento, apresentaram os maiores valores de altura e di\ue2metro, n\ue3o se diferenciando das intermedi\ue1rias com rela\ue7\ue3o ao di\ue2metro do colo. N\ue3o houve diferen\ue7as com rela\ue7\ue3o \ue0 massa seca da parte a\ue9rea e n\ufamero, massa seca, comprimento total e di\ue2metro das ra\uedzes advent\uedcias das mudas em fun\ue7\ue3o do tipo de miniestacas. Ap\uf3s a transfer\ueancia das mudas para a casa de vegeta\ue7\ue3o, a sobreviv\ueancia foi alta, com m\ue9dia de 94,7 % para apicais, 96,3 % para intermedi\ue1rias e 96,6 % para basais. Aos 60 dias ap\uf3s o plantio, apesar das diferen\ue7as observadas no di\ue2metro e altura das mudas ao final da fase de viveiro, n\ue3o houve diferen\ue7a no crescimento em altura, di\ue2metro e massa seca do caule, folhas e sistema radicular, em fun\ue7\ue3o dos tratamentos