7 research outputs found
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