Eucalyptus Grandis Seedlings Research Articles

Measuring water stress in Eucalyptus grandis Hill ex Maiden seedlings planted into pots

A pot trial incorporating various watering regimes was initiated to assess: 1) water stress in Eucalyptus grandis seedlings, and 2) the efficacy of different types of research equipment in quantifying these levels of water stress for applied research. There were two dry soil treatments differing in terms of seedling root plug moisture at transplanting, dry (DD) and wet (WD), respectively, and three treatments consisting of well watered seedlings transplanted into wet soil (WWD, WWW and control). Treatment WWW was re-watered when seedlings were water stressed. The control was maintained at field capacity for the entire trial period. Seedling physiology was assessed by shoot water potential, stomatal conductance and chlorophyll fluorescence. Seedlings with dry root plugs, planted into dry soil were dead one to two days after planting. A wet root plug at the time of transplanting increased seedling shoot water potential and survival for up to three days in dry soil. Planting into wet soil increased shoot water potential for the duration of the trial and was also associated with new root growth. This study indicated that both the pressure chamber and the porometer provided simple and easy to interpret measures of water stress in E. grandis seedlings. Measurements of chlorophyll fluorescence did not significantly reflect treatment effects.

Aparecimento de folhas em mudas de eucalipto estimado por dois modelos

O objetivo deste trabalho foi avaliar e comparar os modelos do Filocrono e de Wang e Engel para estimativa do aparecimento de folhas em mudas de Eucalyptus grandis e E. saligna. Foram instalados dois experimentos em Santa Maria em 2005 e 2006, um, em campo, com nove épocas de semeadura, e o outro, em casa, de vegetação com duas épocas de semeadura. Os modelos usados foram o do Filocrono, que assume uma relação linear entre taxa de aparecimento de folhas e temperatura, e o de Wang e Engel, que assume uma relação não-linear entre taxa de aparecimento de folhas e temperatura. As quatro primeiras épocas de semeadura em campo foram usadas para estimar os coeficientes dos modelos utilizados. As épocas de semeadura restantes do experimento em campo e as duas épocas de semeadura, em casa de vegetação, foram utilizadas como dados independentes para avaliar os modelos. O modelo de Wang e Engel proporcionou estimativa mais precisa do número de folhas, com valor da raiz do quadrado médio do erro de 2,7 e 3,7 folhas, comparado com o modelo do Filocrono com 7,1 e 10 folhas para E. grandis e E. saligna, respectivamente.

Nutrição mineral de mudas de eucalipto produzidas sob diferentes lâminas de irrigação e substratos

Este trabalho teve como objetivo avaliar os efeitos das lâminas brutas de irrigação na concentração de nutrientes de mudas de Eucalyptus grandis, produzidas em diferentes substratos. O experimento foi realizado na Camará - Mudas Florestais, em Ibaté, SP, e constituiu-se de um fatorial 5 x 4, sendo cinco lâminas brutas de irrigação diárias (6, 8, 10, 12 e 14 mm), aplicadas em diferentes horários (10, 13 e 16 h), e quatro substratos (FB - fibra de coco; CPV - casca de pinus e vermiculita; CATV - casca de pinus, carvão, turfa e vermiculita; e um MIX - 70 % de CPV e 30 % de FB). Foram determinadas os conteúdos dos nutrientes na parte aérea e no sistema radicular das mudas. Os resultados indicaram que houve influência das lâminas de irrigação e dos substratos no conteúdo dos nutrientes das mudas com maior acúmulo dos mesmos à medida que o fornecimento de água foi maior. As plantas crescidas nos substratos FB e CPV registraram os maiores acúmulos de nutrientes. CPV foi o melhor em se tratando do acúmulo dos macronutrientes nas raízes e também, juntamente com FB, o melhor para o acúmulo dos micronutrientes nas raízes e na parte aérea. Não houve influência dos substratos no acúmulo dos macronutrientes na parte aérea, porém houve das lâminas de irrigação.

Temperature effects on wood anatomy, wood density, photosynthesis and biomass partitioning of Eucalyptus grandis seedlings

Wood density, a gross measure of wood mass relative to wood volume, is important in our understanding of stem volume growth, carbon sequestration and leaf water supply. Disproportionate changes in the ratio of wood mass to volume may occur at the level of the whole stem or the individual cell. In general, there is a positive relationship between temperature and wood density of eucalypts, although this relationship has broken down in recent years with wood density decreasing as global temperatures have risen. To determine the anatomical causes of the effects of temperature on wood density, Eucalyptus grandis W. Hill ex Maiden seedlings were grown in controlled-environment cabinets at constant temperatures from 10 to 35 degrees C. The 20% increase in wood density of E. grandis seedlings grown at the higher temperatures was variously related to a 40% reduction in lumen area of xylem vessels, a 10% reduction in the lumen area of fiber cells and a 10% increase in fiber cell wall thickness. The changes in cell wall characteristics could be considered analogous to changes in carbon supply. Lumen area of fiber cells declined because of reduced fiber cell expansion and increased fiber cell wall thickening. Fiber cell wall thickness was positively related to canopy CO2 assimilation rate (Ac), which increased 26-fold because of a 24-fold increase in leaf area and a doubling in leaf CO2 assimilation rate from minima at 10 and 35 degrees C to maxima at 25 and 30 degrees C. Increased Ac increased seedling volume, biomass and wood density; but increased wood density was also related to a shift in partitioning of seedling biomass from roots to stems as temperature increased.

Modeling Grouped Survival Data with Time-Dependent Covariates

In this article, proportional hazards and logistic models for grouped survival data were extended to incorporate time-dependent covariates. The extension was motivated by a forestry experiment designed to compare five different water stresses in Eucalyptus grandis seedlings. The response was the seedling lifetime. The data set was grouped since there were just three occasions in which the seedlings was visited by the researcher. In each of these occasions also the shoot height was measured and therefore it is a time-dependent covariate. Both extended models were used in this example, and the results were very similar.

Effects of leaf and branch removal on carbon assimilation and stem wood density of Eucalyptus grandis seedlings

The rate of leaf CO2 assimilation (Al) and leaf area determine the rate of canopy CO2 assimilation (Ac) can be thought proportional to assimilate supply for growth and structural requirements of plants. Partitioning of biomass within plants and anatomy of cells within stems can determine how assimilate supply affects both stem growth and wood density. We examined the response of stem growth and wood density to reduced assimilate supply by pruning leaf area. Removing 42% of the leaf area of Eucalyptus grandis Hill ex Maiden seedlings did not stimulate leaf-level photosynthesis (Al) or stomatal conductance, contrary to some previous studies. Canopy-level photosynthesis (Ac) was reduced by 41% immediately after pruning but due almost solely to continued production of leaves, and was only 21% lower 3 weeks later. Pruning consequently reduced seedling biomass by 24% and stem biomass by 18%. These reductions in biomass were correlated with reduced Ac. Pruning had no effect on stem height or diameter and reduced wood density to 338 kg m−3 compared to 366 kg m−3 in control seedlings. The lower wood density in pruned seedlings was associated with a 10% reduction in the thickness of fibre cell walls, and as fibre cell diameter was invariant to pruning, this resulted in smaller lumen diameters. These anatomical changes increased the ratio of cross-sectional area of lumen to area cell wall material within the wood. The results suggest changes to wood density following pruning of young eucalypt trees may be independent of tree volume and of longer duration.

Propriedades químicas do solo e nutrição do eucalipto em função da aplicação de lodo de esgoto

A aplicação do lodo de esgoto em plantações florestais é uma das alternativas para resolver o problema da disposição final desse resíduo. O objetivo deste trabalho foi avaliar se a aplicação de biossólido melhora a fertilidade do solo e o estado nutricional de mudas de Eucalyptus grandis. O experimento foi montado em colunas de PVC de 20 cm de diâmetro, com nove tratamentos (testemunha, adubação mineral, doses crescentes de biossólido variando de 10 a 160 t ha-1) e quatro repetições. O experimento foi realizado durante 12 meses após o plantio das mudas. O biossólido influenciou mais a acidez do que outros atributos químicos do solo. Os teores de N, P e S nas folhas correlacionaram-se com a CTC e com o teor de C orgânico do solo, tendo essas variáveis apresentado valores significativamente mais elevados nas doses de 80 e 160 t ha-1. Observou-se diminuição da matéria orgânica do solo nas doses de 10 a 40 t ha-1. O biossólido alcalino diminui a acidez do solo e melhora sua fertilidade, aumentando a disponibilidade da maioria dos nutrientes.

Why does phosphorus limitation increase wood density in Eucalyptus grandis seedlings?

Wood density influences both the physiological function and economic value of tree stems. We examined the relationship between phosphorus (P) supply and stem wood density of Eucalyptus grandis Hill ex Maiden seedlings grown with varying soil P additions and determined how changes in wood anatomy and biomass partitioning affect the relationship. Plant height, stem diameter and total biomass increased by 400-500% with increasing P supply. Stem wood density decreased sharply from 520 to 380 kg m(-3) as P supply increased to 70 mg P kg(soil) (-1). Further increases in P supply to 1000 mg P kg(soil) (-1) had no effect on wood density. The increase in wood density at low soil P supply arose principally from enhanced secondary wall thickening of stem fiber cells. Cell wall thickness increased from 3.6 to 4.5 microm as soil P supply decreased. Because fiber cell diameter was independent of soil P (12 microm +/- 0.3), the proportion of the stem occupied by cell wall material increased as P supply declined. The enhanced secondary wall thickening of stem fiber cells at low P supply was not associated with changes in whole-plant biomass partitioning. Instead, low P supply appeared to alter biomass partitioning within the stem in favor of secondary wall thickening. Thus, increased wood density in E. grandis seedlings grown at low P soil supply was associated with inhibited stem cambial activity, resulting in an increased proportion of photoassimilates available for secondary wall thickening of fiber cells.

Leaf inorganic phosphorus as a potential indicator of phosphorus status, photosynthesis and growth of Eucalyptus grandis seedlings

In eucalypts the reduction in CO 2 assimilation and total leaf area at low phosphorus (P) supply is not associated with lower leaf total P concentrations. We tested the hypothesis that the leaf concentration of inorganic phosphorus ([P i]) may be a better indicator of P nutrition status in Eucalyptus grandis W. Hill ex Maiden by growing seedlings in P deficient soil supplemented with P supplies ranging from 3 to1000 mg kg −1. Height, biomass accumulation, gas exchange, chlorophyll fluorescence and concentrations of total P ([P t]), organic P ([P o]) and [P i] of the last fully expanded leaves were measured when harvested at 19 weeks. All parameters of growth increased with larger applications of soil P with most becoming saturated at additions of 500 mg P kg −1 soil. Soil P supply had larger effects on biomass and canopy leaf area, by both increased in leaf initiation and expansion, than on CO 2 assimilation ( A). Leaf [P t] and [P o] concentrations were largely invariant to soil P supply and were not correlated with any of the measured growth and photosynthetic parameters. By contrast, leaf [P i] increased from 171 to 398 mg kg −1 with increasing soil P supply. Furthermore, number of leaves, total leaf area and seedling biomass increased exponentially with leaf [P i], while individual leaf area and A increased linearly with leaf [P i], and quantum yield of photosystem II similarly increased, and non-photochemical quenching decreased, with increasing leaf [P i]. The response of A to internal CO 2 concentration ( C i) indicated that at lower P supplies A became increasingly restricted by limitations associated with Rubisco and RuBP regeneration. Stomatal limitation may in part be masking the full effect of P supply on A as C i declined with either increasing soil P or leaf [P i] supply. We conclude that leaf [P i] was a potentially better indicator than [P t] or [P o] for correlating the effects of soil P supply on growth and photosynthesis of E. grandis. Furthermore, as A achieved at saturating C a increased with increasing P supply leaf [P i], these findings suggest that a greatly increased rate of canopy assimilation could be achieved at higher P supply in response to the expected increase in global CO 2 levels.

Imazapyr root exudation from eucalypt seedlings cultivated in nutritive solution

Imazapyr has been used in Brazilian eucalypt cultivation for the maintenance of clearings and coppicing control in areas undergoing stand reform. However, inquiries have been made as to the final fate of the molecule. Imazapyr root exudation in eucalypt plants was evaluated through a bioassay under greenhouse conditions, by applying different herbicide doses (0.000, 0.375, 0.750, 1.125, and 1.500 kg ha-1 a.i.) on Eucalyptus grandis seedlings derived from vegetative propagation, hydroponically cultivated in 2.500 ml vases. Forty-day-old seedlings of the same clone were used as bioindicators, transplanted to the vases two days after herbicide application. After a period of 13 days of coexistence, the sprayed plants were removed and discarded; ten days later, the visual symptoms of toxicity were evaluated and the total dry biomass (aerial part and roots) of the bioindicators were determined. The lowest herbicide dose (0.375 kg ha-1 a.i.) affected the total biomass and growth, being most evident in the aerial part, with larger I50 for root dry biomass. The E. grandis seedlings exuded imazapyr, and/or its metabolites, in concentrations capable of affecting the growth of plants of the same species.

Impact of nitrogen and phosphorus fertilization on drought responses in Eucalyptus grandis seedlings

Water and nutrients are two of the most important factors controlling the growth of trees. Numerous studies show that fertilization is most effective when trees are not water-stressed and that irrigation is most effective when nutrients are not scarce. The goal of this work was to test the responses of Eucalyptus grandis seedlings to drought as affected by soil type and fertilization with nitrogen (N) or phosphorus (P). Seedlings of E. grandis were planted in pots with two different types of soil: a sandy soil and a clay (black) soil. Plants were fertilized with N or P, and half of them were water-stressed. Fertilization did not affect the growth reduction brought about by drought in the red sands; in the black soil, plants fertilized with P showed a moderate growth increase under drought, compared to non-fertilized plants. Dry mass allocation to roots was decreased by fertilization in water-stressed and well-watered plants in the sandy soil, and in well-watered plants of the black soil, but it increased in water-stressed plants fertilized with N in the black soil. Water use efficiency (WUE), i.e., the grams of water transpired per gram of dry mass accumulated, was not altered by fertilization or water stress in the black soil, although it increased with P fertilization in well-watered plants in the sandy soil. Osmotic adjustment was observed only in plants fertilized with P in the black soil, and in non-fertilized plants in the sandy soil. Osmotic adjustment in water-stressed plants was associated with an increased stomatal conductance. We conclude that water stress tolerance strategies are altered by fertilization depending on soil properties, and that fertilization with P is recommended in black soils even if a moderate drought is likely to occur, but on sandy soils fertilization is recommended only under good water supply.

Preliminary results of a floating subirrigation system (“Aquaforest system”) as an alternative to conventional tree nurseries

A new methodology for tree seedling production (“Aquaforest system”) based on a continuous floating subirrigation system was developed and tested using creeks with different nutrient levels. Eucalyptus grandis seedlings were produced in water from polluted and clean creeks, and compared to conventional tree nursery production. The growth variables analyzed in the seedling phase were: survival, height, diameter, shoot and root dry weight, leaf area, and root/shoot ratio. Water and substrate were analyzed, as well as leaf nutritional status. Plant survival was 100% in all treatments. Height and diameter were greater in the higher nutrient water treatment. Leaf area and dry weight of plants produced in the higher nutrient water treatment were similar to those of the control. The results showed that polluted water can represent a good nutrient source. The preliminary results show that the “Aquaforest system” can be a viable alternative for tree seedling production.

Crescimento de mudas de Eucalyptus grandis em diferentes tamanhos de tubetes e fertilização N-P-K

O experimento foi instalado com o objetivo de estudar o crescimento de mudas de Eucalyptus grandis produzidas em diferentes tamanhos de tubetes e fertilização N-P-K. O substrato utilizado foi uma mistura de 80% de composto orgânico (CO) e de 20% de moinha de carvão (MC), adubados com a presença e ausência dos elementos N, P e K. Como embalagens foram utilizados quatro tamanhos de tubetes de plástico rígido, com volumes de 50, 110, 200 e 280 cm³. Os volumes dos tubetes devem ser considerados para produção de mudas de Eucalyptus grandis. Apesar de os melhores crescimentos terem sido obtidos nos maiores tubetes, estes não devem ser utilizados, uma vez que as alturas das mudas estão acima das tecnicamente ótimas para o plantio, além de o custo de produção ser onerado. Aos 60 dias de idade as mudas ainda estão pequenas e bastante tenras, sem o endurecimento adequado para o plantio no campo. Aos 120 dias após a semeadura a restrição ao crescimento das raízes e da altura das mudas é afetada, mesmo nos tubetes de maiores volumes, não sendo essa a idade indicada. O tubete de 110 cm³ de volume deve ser considerado para mudas com 90 dias de idade.

Using chlorophyll fluorescence to determine stress inEucalyptus grandisseedlings

Synopsis Since several environmental factors affect the functioning of the photosynthetic system, the status of the photosynthetic apparatus is a good indicator of the plant in terms of stress and stress adaptation. The measurement of chlorophyll fluorescence with a portable fluorimeter has been shown to be a useful non-destructive method for the investigation of the structure and function of the photosynthetic apparatus. A quantitative analysis of fluorescence emission, called the JIP-test, has also been introduced by which the behaviour of the photosynthetic system in response to environmental changes can be monitored. A pilot trial was conducted to determine the effect of light, water and nutrient stress on the fluorescence emission of Eucalyptus grandis seedlings. Flourescencc measurements were made on potted plants with a Hansatech Plant Efficiency Analyser, everyone to two days from stress initiation until trial termination. The results indicate that water and light stress in E. grandis seedlings ca...

Toward a hierarchical concept of plant stress

A number of attempts have been made to obtain a clear definition of biological stress. However, in spite of the efforts, some controversies on the concept of plant stress remain. The current versions are centered either on the cause (stress factor) or on the effect (stress response) of environmental stress. The objective of this study was to contribute to the definition of stress, using a hierarchical approach. Thus, we have performed an analysis of the most usual stress concepts and tested the relevance of considering different observation scales in a study on plant response to water deficit. Seedlings of Eucalyptus grandis were grown in vitro at water potentials ranging from -0.16 to -0.6 MPa, and evaluated according to growth and biochemical parameters. Data were analyzed through principal component analysis (PCA), which pointed to a hierarchical organization in plant responses to environmental disturbances. Growth parameters (height and dry weight) are more sensitive to water deficit than biochemical ...

Photosynthetic parameters in seedlings of Eucalyptus grandis as affected by rate of nitrogen supply

AbstractSeedlings of Eucalyptus grandis were grown at five different rates of nitrogen supply. Once steady‐state growth rates were established, a detailed set of CO2 and water vapour exchange measurements were made to investigate the effects of leaf nitrogen content (N), as determined by nitrogen supply rate, on leaf structural, photosynthetic, respiratory and stomatal properties. Gas exchange data were used to parametrize the Farquhar–von Caemmerer photosynthesis model. Leaf mass per area (LMA) was negatively correlated to N. A positive correlation was observed between both day (Rd) and night respiration (Rn) and N when they were expressed on a leaf mass basis, but no correlation was found on a leaf area basis. An Rd/Rn ratio of 0·59 indicated a significant inhibition of dark respiration by light. The maximum net CO2 assimilation rate at ambient CO2 concentration (Amax), the maximum rate of potential electron transport (Jmax) and the maximum rate of carboxylation (Vcmax) significantly increased with N, particularly when expressed on a mass basis. Although the maximum stomatal conductance to CO2 (gscmax) was positively correlated with Amax, there was no relationship between gscmax and N. Leaf N content influenced the allocation of nitrogen to photosynthetic processes, resulting in a decrease of the Jmax/Vcmax ratio with increasing N. It was concluded that leaf nitrogen concentration is a major determinant of photosynthetic capacity in Eucalyptus grandis seedlings and, to a lesser extent, of leaf respiration and nitrogen partitioning among photosynthetic processes, but not of stomatal conductance.

Parâmetros morfológicos na avaliação de qualidade de mudas de Eucalyptus grandis

Este experimento foi instalado com o objetivo de estudar os parâmetros morfológicos nas avaliações da qualidade de mudas de Eucalyptus grandis produzidas em diferentes tamanhos de tubetes. O substrato utilizado foi uma mistura de 80% de composto orgânico (CO) e de 20% de moinha de carvão (MC), adubados com a presença e ausência dos elementos N, P e K. Como embalagens foram utilizados quatro tamanhos de tubetes de plástico rígido, com volumes de 50, 110, 200 e 280 cm³. A adoção da altura e da relação altura/peso de matéria seca da parte aérea deve ser considerada, por terem sido estes os parâmetros que apresentaram boa contribuição relativa à qualidade das mudas, sem contudo ser um processo destrutivo. A adoção somente da altura para estimar a qualidade de mudas, aos 90 dias de idade no tubete de 110 cm³ de volume, poderá ser utilizada por apresentar boa contribuição relativa e por ser um parâmetro de fácil determinação e não ser um método destrutivo, além de sua medição ser muito fácil.

Production of transgenic Eucalyptus grandis x E. urophylla using the sonication-assisted Agrobacterium transformation (SAAT) system.

A method for genetic transformation of germinating seeds and seedlings of Eucalyptus grandis × E. urophyllais described using the sonication-assisted Agrobacterium-mediated transformation (SAAT) system. Seeds germinated for 2 d, and 15-d-old seedlings, sonicated for 30 s, had the highest percentage of β-glucuronidase (GUS) transient expression (21.7 and 37.4%, respectively). Pre-sonication greatly enhanced the efficiency of transformation. The differential transformation of tissues was also investigated, with seeds imbibed for 2 d having over 90% of the blue sectors localised in cotyledons and in the intersection of the hypocotyls and roots, whereas in 5-d-old seedlings, 70% of GUS activity was detected in cotyledons. However, 15-17-d-old seedlings had around 60% of transformed sectors localised in the first pair of leaves. The efficiency of the method was also assessed using a chimeric construct containing the Lhcb1*2 gene of the 28 kDa chlorophyll a/b binding pea protein from the LHCII antenna. Four stable transformants were confirmed by genomic blotting.

Influência da idade da muda de Eucalyptus grandis no desenvolvimento da lagarta-rosca Nomophila sp.

O objetivo deste trabalho foi estudar a influência da idade das mudas de Eucalyptus grandis (Myrtaceae) no desenvolvimento da lagarta-rosca Nomophila sp. (Lepidoptera: Pyralidae). Esse inseto foi alimentado em laboratório (24±2°C, 80±15% de UR e fotofase de 12 horas) com folhas de eucalipto com 20-30 dias ou com 50-60 dias de idade. Os parâmetros observados foram: número, duração e caracterização dos estádios, largura da cápsula cefálica, comprimento do corpo, duração da fase larval, relação entre número de estádios e o sexo, viabilidade e comportamento das lagartas de Nomophila sp. Esse inseto mostrou melhor desenvolvimento em todos os parâmetros observados, em mudas de eucalipto com 20-30 dias do que em mudas com 50-60 dias de idade, quando o caule está mais enrijecido. Isto reforça a necessidade de se realizar uma adubação balanceada nas mudas de E. grandis, como forma de acelerar seu desenvolvimento, e torná-las morfologicamente menos favoráveis ao desenvolvimento das lagartas de Nomophila sp.

Above ground biomass and nutrient uptake of three tree species ( Eucalyptus camaldulensis, Eucalyptus grandis and Dalbergia sissoo) as affected by irrigation and fertiliser, at 3 years of age, in southern India

Seedlings of Eucalyptus camaldulensis, Eucalyptus grandis and Dalbergia sissoo were planted in a two-replicate split-plot factorial trial with four irrigation and three fertiliser treatments in Hosakote Forest station in southern India in September 1991. Irrigation was applied at the rate of 0, 2.5, 5 and 7.5 mm per day. Natural rainfall was approximately 800 mm per year distributed between June and November in two monsoon seasons. NPK fertiliser was applied three times in spade-slit dressings at 9, 18 and 27 months from planting at a zero rate, a medium rate and a rate four times that. Over the life of the trial N was applied at the rate of 0, 80 or 320 kg/ha; P was applied at the rate of 0, 7.5 or 30 kg/ha and K at 0, 25 or 100 kg/ha. In October 1994 when the trees were 37 months from transplanting, a biomass and nutrient content determination was made. The two eucalyptus had a total dry weight averaging 45.3 tonnes/ha while the Dalbergia had an average dry weight of only 7.6 tonnes. There were no interactions between species and treatments. Irrigation increased dry weight linearly across treatments and by 74% in the highest irrigation rate. Irrigation increased stem wood weight by 90% but branch and leaf weight by only 40%. Fertiliser increased dry weight by 23% and increased branch weight by a higher percentage than leaf weight. The two eucalyptus had accumulated a stem volume of 60 m 3/ha at a rate of 20 m 3/ha per year. Nutrient content increased with dry weight but not in proportion, so that nutrient concentrations in the higher rates of both irrigation and fertiliser treatments were reduced, in some instances to marginal levels. Thus, the natural fertility of the site was stressed by the high growth rates.