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A recent increase in published studies of lianas has been paralleled by a proliferation of protocols for censusing lianas. This article seeks to increase uniformity in liana inventories by providing specific recommendations for the determination of which taxa to include, the location of diameter measurement points on individual stems, the setting of minimum stem diameter cutoffs, the treatment of multiple-stemmed and rooted clonal groups, and the measurement of noncylindrical stems. Use of more uniform liana censusing protocols may facilitate comparison of independently collected data sets and further our understanding of global patterns in liana abundance, diversity, biomass, and dynamics.

Foram avaliados o crescimento e o desenvolvimento da cultivar de algodoeiro IAC 23 em espaçamentos ultra-adensado, adensado e convencional entre fileiras e com número variado de plantas por metro linear. O experimento foi implantado na área experimental da Universidade de São Paulo/Escola Superior de Agricultura "Luiz de Queiroz", Piracicaba (SP), no ano agrícola 2001/2002. O delineamento experimental compreendeu um esquema fatorial, em blocos ao acaso, com 4 repetições, sendo três espaçamentos entre linhas (0,38; 0,76 e 0,95 m) e quatro densidades de plantas por metro linear (5, 8, 11 e 14). Os parâmetros avaliados foram: índice de área foliar (IAF) e massa seca da parte aérea em todos os estádios da cultura (aparecimento do primeiro botão floral; abertura da primeira flor; maturação fisiológica; primeiro capulho; completa maturação); altura média de plantas, altura de inserção do 1.º ramo frutífero, diâmetro do caule, número de ramos vegetativos e frutíferos e número de internódios, verificados por ocasião da colheita. Nas condições estudadas, a cultivar completou seu ciclo em 161 dias. Constatou-se interação significativa entre espaçamento e densidade para altura média das plantas, número de ramos frutíferos e de internódios e que diferentes configurações de semeadura alteram o crescimento e o desenvolvimento do algodoeiro. The growth and development of cotton IAC 23 under ultra-narrow, narrow and conventional rows and different numbers of plants for linear meter have been evaluated. The experiment was lead in the experimental area of the University of São Paulo/ESALQ, Piracicaba, State of São Paulo, Brasil, in 2001/2002. The experimental design was a randomized complete block, in factorial scheme, with 4 replications, being three rows (0.38; 0.76 and 0.95 m) and four densities of plants for linear meter (5, 8, 11 and 14). They were analyzed: leaf area index (LAI) and plant shoot dry mass in all phenological phases (emergence of first flower buds, opening of first flower; physiological maturation; first open boll; complete maturation); average plant height, insertion of the first fruit branch, stem diameter, number of vegetative and fruit branches and number of internodes, were estimated by harvest occasion. Under the studied conditions, the cultivar completed its cycle in 161 days. Interaction between rows and densities of plants occurred to average plant height; number of fruit branches and internodes. Different configurations of rows modified the growth and the development of the cotton plants.

Allometric equations to estimate total aboveground alive biomass (B) or crown projection area (C) of ten caatinga species based on plant height (H) and/or stem diameter at ground level (DGL) or at breast height (DBH) were developed. Thirty plants of each species, covering the common range of stem diameters (3 to 50 cm), were measured (C, H, DGL, DBH), cut at the base, separated into parts, weighted and subsampled to determine dry biomass. Wood density (p) of the stem and the largest branches was determined. B, C, H and p ranged from 1 to 500 kg, 0.2 to 112 m², 1.3 to 11.8 m, and 0.45 to 1.03 g cm-3. Biomass of all 10 species, separately or together (excluding one cactus species), could be estimated with high coefficients of determination (R²) using the power equation (B = aDGLb) and DGL, DBH, H or combinations of diameter, height and density. Improvement by multiplying H and/or p to DGL or DBH was small. The mixed-species equation based only on DBH (valid up to 30 cm) had a = 0.173 and b = 2.295, similar to averages of these parameters found in the literature but slightly lower than most of those for humid tropical vegetation. Crown area was significantly related to diameter, height and biomass. Equações alométricas foram desenvolvidas para estimar a biomassa aérea viva (B) e a área de projeção da copa (C) de dez espécies da caatinga, com base na altura da planta (H) e/ou do diâmetro do caule ao nível do solo (DNS) ou à altura do peito (DAP). Trinta plantas de cada espécie, cobrindo a faixa usual de diâmetros (3 a 50 cm), foram medidas (C, H, DNS, DAP), cortadas na base, separadas em partes, pesadas e subamostradas para determinação da biomassa seca. A densidade (p) da madeira dos caules e galhos maiores foi determinada. B, C, H e p variaram de 1 a 500 kg, 0,2 a 112 m², 1,3 a 11,8 m e 0,45 a 1,03 g cm-3. A biomassa das 10 espécies, separadamente ou em conjunto (exceto pela espécie de Cactaceae), foi estimada com alto coeficiente de determinação (R²), usando a equação de potência (B = aDNSb) e DNS, DAP ou combinações de diâmetro, altura e densidade. A melhora com a multiplicação de DNS ou DAP por H e/ou p foi pequena. A equação de DAP (válida até 30 cm) para o conjunto das nove espécies teve a = 0,173 e b = 2,295, semelhantes aos valores das médias das equações encontradas na literatura, mas um pouco abaixo dos referidos para vegetação tropical úmida. A projeção das copas foi significativamente relacionada com diâmetros do caule, alturas e biomassas.

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:21:05Z No. of bitstreams: 0Bitstream added on 2014-05-27T14:44:51Z : No. of bitstreams: 1 2-s2.0-6344256220.pdf: 1190015 bytes, checksum: 7c3abf159e14677c993ad658abe3acc0 (MD5) Made available in DSpace on 2014-05-27T11:21:05Z (GMT). No. of bitstreams: 0 Previous issue date: 2004-06-01 The objective of this paper was to evaluate the phenotypical plasticity of external morphology of Lippia alba in response to two luminosity level and four organic-mineral fertilization level. The morphological plasticity was quantified by the phenotypic variation intensity of the morphological characters (ramifications, leafs, inflorescences, flowers, height, stem diameter, leaf blade length, foliar blade breadth and space between branches). It was possible to verify significant effect as a consequence of luminosity and substratum variations. However, the interaction between these factors was not observed suggesting that they act independently. The majority of characters revealed high magnitude of phenotypical plasticity. The results obtained suggest that luminosity intensity and substratum quality contribute to amplify the phenotypical expression of Lippia alba. Bacharel e Licenciado em Cie. Biol. Universidade Federal de Juiz de Fora Depto. de Prod. Vegetal/Horticultura Faculdade de Ciencias Agronomicas UNESP, Caixa Postal 237, Cep: 18603-970, Botucatu - SP Faculdade de Farmacia e Bioquimica UFJF Departamento de Biologia UFJF UNESP Faculdade de Ciencias Agronomicas Campus de Botucatu-SP Depto. de Prod. Vegetal/Horticultura Faculdade de Ciencias Agronomicas UNESP, Caixa Postal 237, Cep: 18603-970, Botucatu - SP UNESP Faculdade de Ciencias Agronomicas Campus de Botucatu-SP

International audience; Stem profile equations were developed for young trembling aspen (Populus tremuloides Michx.) growing on 6 different sites in northern Ontario. The objective was to develop a model using stem diameter at any height to predict stem diameter at other heights and then compare the model among sites. The 262 sample trees were split into calibration (180) and validation (82) sets. Four stem profile models having from 1 to 3 parameters were tested for parameter significance for each site, and then compared among sites. Data analysis was performed using bootstrap methods. One of the 4 models was not significantly different (P > 0.278) among sites. Validation of this model produced mean prediction errors and mean relative prediction errors of less than 0.001 cm and 0.09%, respectively; standard deviations of these errors were 0.15 cm and 4.09%, respectively. The presented method can be used to develop stem profile equations that are applicable to a broad range of growing conditions.; Équations de profil de tige de jeunes trembles de l'Ontario septentrional. On a mis au point des équations de profil de tige pour des trembles (Populus tremuloides Michx.) se développant dans 6 stations différentes du nord de l'Ontario. L'objectif était de créer un modèle utilisant le diamètre pris à n'importe quelle hauteur pour prédire le diamètre à d'autres hauteurs et ensuite pour comparer les modèles selon les sites. Les 262 arbres témoins ont été affectés soit au calibrage (180) soit à la validation (82). Sur quatre modèles comportant de 1 à 3 paramètres, on a d'abord testé le caractère significatif des paramètres dans chaque site, puis procédé à des comparaisons entre sites. Pour l'analyse des données on a utilisé les méthodes " bootstrap ". L'un des 4 modèles ne présentait pas de différence significative (P > 0,278) entre sites. La validation de ce modèle inique une prédiction d'erreur moyenne et d'erreur relative moyenne respectivement inférieurs à 0,001 cm et 0,09 %. Les écarts types de ces erreurs étaient de 0,15 cm et 4,09 %. La méthode présentée peut être utilisée pour développer des équations de profil de tige applicables à une vaste gamme de conditions de croissance.

Estudou-se o efeito da inoculação com o fungo micorrízico arbuscular (FMA), Glomus macrocarpum, da fumigação do substrato e da adição de fósforo solúvel (60, 120, 240 e 480 mg kg-1 de P no solo) sobre as variáveis altura, número de folhas e diâmetro do caule de plantas de mamoeiro cv. Sunrise Solo.O FMA edoses crescentes de fósforo, isoladamente, exerceram efeitos significativos sobre essas variáveis. Não houve efeito significativo do fator fumigação do substrato. O efeito da inoculação foi mais acentuado no tratamento com adição de 60 mg kg-1 de P no solo. A inoculação com G. macrocarpum reduziu a necessidade de fósforo para o mamoeiro, tanto que as variáveis estudadas em plantas inoculadas na ausência de adubação fosfática não diferiram de plantas não inoculadas em substrato adicionado de mais de 240 mg kg-1 de P no solo. The effects of inoculation with arbuscular mycorrhizal fungus (AMF), substratum fumigation, and addition of soluble phosphate on papaya plant cultivar "Sunrise Solo" parameters (height, leaf number, and stem diameter) were studied. Separate treatments with AMF inoculation (Glomus macrocarpum) and increasing phosphorus levels (60, 120, 240, and 480 mg kg-1 of P in soil) influenced these parameters significantly, while the factor substratum fumigation had no significant effect. The inoculation effect was most expressive when 60 mg kg-1 of P in soil was added. Such was the reduction in phosphorus requirement of papaya by Glomus macrocarpum inoculation, that the studied parameters between inoculated plants without phosphate addition and not-inoculated ones in substratum enriched with over 240 mg kg-1 of P in soil did not differ.

Este trabalho tem como objetivo avaliar a ação do ácido giberélico (AG3) em plantas crisântemo de corte 'Viking' quanto a parâmetros fenométricos, melhor época e concentração da aplicação para obter-se hastes de melhor qualidade no cultivo de verão/outono. Avaliou-se o efeito de cinco épocas de aplicação (sem aplicação, aplicação na segunda, quarta, oitava e décima semana após o plantio) e quatro concentrações (0, 100, 200 e 300 mg.L-1 de GA3). Verificou-se que as maiores alturas foram obtidas com as aplicações na segunda e quarta semanas de cultivo e nas concentrações entre 200 a 300 mg.L-1. O maior diâmetro de haste e pedúnculo floral foram obtidos com a aplicação de 100 a 200 mg.L-1 GA3 na quarta semana. A concentração de 200 mg.L-1 de GA3, independente da época de aplicação proporcionou a antecipação do florescimento em cinco dias, todas as concentrações aplicadas a partir da oitava semana provocaram o clareamento do disco floral. This research has the purpose to value the action of the gibberellic acid (GA3) in cut chrysanthemum 'Viking' as for fenometric parameters, the best time, the frequency and the concentration of the AG3 application to obtain brunches of the best quality in different time of thecultivation. In cultivation during the Summer/Fall, valued the effect of five times the application (2nd, 4th, 8th and 10th week after the plantation) and four concentrations (0, 100, 200 and 300 mg.L-1) in which it was observed that the tallest branches were obtained with applications done during the 2nd and 4th week 200 and 300 mg.L-1, the biggest brunch diameter of the floral peduncle are results of the GA3 of the 100 or 200 mg.L-1 application done on the 4th week. The AG3 200 mg.L-1 concentration independent of the application, the time caused the anticipation of the blossom in a period five days, all the concentration applied from the 8th week on result whiten floral disc.

Plantas de milho podem apresentar variações fenotípicas conforme o ambiente a que estão sujeitas durante seu crescimento. O objetivo deste trabalho foi verificar se as alterações em caracteres fenológicos de plantas de milho, causadas pela presença de plantas daninhas, poderiam indicar o início da interferência e também o momento de início do seu controle. Os tratamentos referem-se a períodos de convivência do milho com as plantas daninhas - 0 a 7, 0 a 14, 0 a 21, 0 a 28, 0 a 35, 0 a 42, 0 a 49 e 0 a 56 dias após a emergência (DAE) do milho - e as testemunhas com e sem convivência durante todo o ciclo. A altura de plantas, o diâmetro do colmo e o número de folhas foram avaliados a cada sete dias, até 56 DAE e no pendoamento (75 DAE). Avaliou-se também o rendimento de grãos de milho. O início da interferência das plantas daninhas nas três variáveis avaliadas e no rendimento de grãos foi simultâneo, a partir de 28 DAE. Os efeitos da interferência foram irreversíveis, não havendo recuperação das plantas após a retirada do estresse causado pela presença das plantas daninhas; portanto, o uso de caracteres fenológicos na indicação do início de controle não se mostrou apropriado. A field study was carried out to identify phenological parameters in corn indicative of the onset of weed interference and the moment to start weed control. The treatments consisted of different periods of weed/crop coexistence: 0 to 7, 0 to 14, 0 to 21, 0 to 28, 0 to 35, 0 to 42, 0 to 49 and 0 to 56 days after corn emergence (DAE), and checks with and without weeds. Plant height, stem diameter and leaf number were evaluated at every interval of seven days until 56 DAE and at tasseling (75 DAE). Yield was also evaluated. The effect of weed on the three parameters evaluated and on yield reduction started simultaneously at 28 days after corn emergence. The effects on plants were irreversible. The plants were unable to recover after weed competition was removed; therefore, the use of phenological parameters as indicators of the start of weed control was shown to be inappropriate.

As palmeiras apresentam grande demanda por nutrientes. Por este motivo, o efeito da adubação NPK no crescimento de pupunheiras (Bactris gasipaes Kunth) foi estudado durante 30 meses (11/90 a 04/93) em experimento conduzido a campo em solo Aluvial álico (corrigido por meio de calagem) em Ubatuba, SP (clima "Cfa"). Utilizou-se o delineamento de blocos ao acaso, com uma repetição, em esquema fatorial fracionado (½ de 4³), com tratamentos dispostos em dois blocos, parcelas úteis de 24 plantas e bordaduras duplas ao redor. Foram testadas quatro doses de nitrogênio (0, 100, 200 e 400 kg ha-1 ano-1 de N), fósforo (0, 50, 100 e 200 kg ha-1 ano-1 de P2O5) e potássio (0, 50, 100 e 200 kg ha-1 ano-1 de K2O), aplicadas em faixa e divididas em cinco aplicações anuais, utilizando como fontes nitrocálcio, superfosfato triplo e cloreto de potássio. As plantas foram cultivadas no espaçamento de 2 × 1 m, e avaliadas periodicamente quanto ao diâmetro da haste principal, número de perfilhos e porcentagem de plantas perfilhadas. Em solo arenoso e de baixa fertilidade, a pupunheira apresenta resposta linear, positiva e significativa de crescimento às adubações com nitrogênio (N) e potássio (K) e ausência de resposta ao fósforo (P). As primeiras respostas significativas ocorreram três meses depois de iniciadas as adubações diferenciadas. Não houve interações significativas entre N, P e K. O crescimento máximo foi obtido com doses anuais de 400 kg de N, 0 kg de P2O5 e 200 kg de K2O por hectare. Palms have high nutrient demand. For this reason, the effects of NPK fertilization on the initial growth of peach palm (Bactris gasipaes Kunth) were studied in a field experiment, from November 1990 to April 1993. The trial was set up on an allic, previously limed soil, in Ubatuba, SP, Brazil (23º27'S, 45º04'W, 6 m asl; "Cfa" climate). A fractional factorial experimental design (½ of 4³) was utilized, with two blocks, one replication, 24 inner plants per plot and double border rows. Treatments were composed of four rates of nitrogen (0 to 400 kg N ha-1 year-1), phosphorus (0 to 200 kg P2O5 ha-1 year-1) and potassium (0 to 200 kg K2O ha-1 year-1), applied in stripes and divided in five annual applications. The fertilizers used were: calcium nitrate, triple super phosphate and potassium chloride. Plants were cultivated in a 2 × 1 m array, and periodically evaluated in relation to diameter of main stem, number of offshoots and percentage of plants with offshoots. In this sandy and low fertility soil, peach palm growth responses in relation to N and K amendments were linear and positive. Initial responses were observed three months after fertilizer application. No isolated effects of P fertilization, nor significant interactions among fertilizers were observed. Maximum growth responses were reached with 400 kg N ha-1 year-1, 0 kg P2O5 ha-1 year-1 and 200 kg K2O ha-1 year-1.

In the sunflower, in addition to seed yield, it is of interest to evaluate number of leaves plant-1, head diameter, stem diameter and plant height, since these characteristics may be associated with seed yield or lodging. The objective of the work was to determine the optimal sample size (from which the experimental coefficient of variation, CV, can be established) for evaluation of these four characteristics. Fifteen cultivars were evaluated in an experimental design of randomized blocks with ten replications. The characteristics were evaluated using two sampling methods (in a single row of plants or in the two rows from the useable area of each plot) and sample sizes of from two to 18 sampling units, with an interval of two plants. In the two sampling methods, the experimental accuracy, as measured by the CV, increased with increasing sample size. A sample made up of ten sampling units is suitable for assessing the number of leaves, the diameters of the head and stem, and the plant height in cultivars of the sunflower. From this sample size upwards, additional gains in experimental precision are not obtained. This sample size can be used to evaluate plants in a single row or in two rows taken from the useable area of each plot, since there was virtually no difference between sampling methods with regard to experimental accuracy. However, it is most practical and quick to sample in one row of plants. No girassol, além do rendimento de sementes, existe interesse na avaliação do número de folhas, dos diâmetros do capítulo e do caule e da altura da planta, e porque estas características podem estar associadas com o rendimento de sementes ou com o acamamento. O objetivo do trabalho foi determinar o tamanho ideal da amostra (a partir do qual o coeficiente de variação experimental, CV, se estabiliza) para avaliação das quatro características referidas. Quinze cultivares foram avaliadas no delineamento experimental de blocos ao acaso com dez repetições. As características foram avaliadas com dois métodos de amostragem (em uma só fileira de plantas ou nas duas fileiras da área útil da parcela) e tamanhos amostrais de duas a 18 unidades amostrais, com intervalos de duas plantas. Nos dois métodos de amostragem, a precisão experimental, medida pelo CV, aumentou com o aumento do tamanho da amostra. Uma amostra formada por dez unidades amostrais é adequada para avaliação do número de folhas, dos diâmetros do capítulo e do caule e da altura da planta de cultivares de girassol. A partir deste tamanho amostral não se obtém ganhos adicionais na precisão experimental. Este tamanho amostral pode ser usado com a avaliação de plantas em uma só fileira ou em duas fileiras da área útil da parcela, desde que, com ele praticamente não existiram diferenças entre métodos de amostragem, no que se refere à precisão experimental. Contudo, é mais prático e rápido fazer a amostragem em uma só fileira de plantas.

The stable isotopes of hydrogen and oxygen (delta H-2 and delta O-18, respectively) have been widely used to investigate tree water source partitioning. These tracers have shed new light on patterns of tree water use in time and space. However, there are several limiting factors to this methodology (e.g., the difficult assessment of isotope fractionation in trees, and the labor-intensity associated with the collection of significant sample sizes) and the use of isotopes alone has not been enough to provide a mechanistic understanding of source water partitioning. Here, we combine isotope data in xylem and soil water with measurements of tree's physiological information including tree water deficit (TWD), fine root distribution, and soil matric potential, to investigate the mechanism driving tree water source partitioning. We used a 2 m(3) lysimeter with willow trees (Salix viminalis) planted within, to conduct a high spatial-temporal resolution experiment. TWD provided an integrated response of plant water status to water supply and demand. The combined isotopic and TWD measurement showed that short-term variation (within days) in source water partitioning is determined mainly by plant hydraulic response to changes in soil matric potential. We observed changes in the relationship between soil matric potential and TWD that are matched by shifts in source water partitioning. Our results show that tree water use is a dynamic process on the time scale of days. These findings demonstrate tree's plasticity to water supply over days can be identified with high-resolution measurements of plant water status. Our results further support that root distribution alone is not an indicator of water uptake dynamics. Overall, we show that combining physiological measurements with traditional isotope tracing can reveal mechanistic insights into plant responses to changing environmental conditions.

Data from five studies on the relationships between dendrometric measurements and leaf area of Eucalyptus globulus Labill. plantations were pooled and analyzed to develop regression models for the estimation of leaf area of individual trees. The data, collected at two sites in west-central and southwestern Portugal, varied in age from 2 to 19 years and in plant density from 481 to 1560 trees/ha and included both first and second rotation coppice stands. A total of 29 nonlinear regression models were tested and ranked with a multicriteria evaluation (MCE) procedure, based on goodness-of-fit statistics, predictive ability statistics, and collinearity diagnostics. The best models were validated using an independent data set. The final model selection was based on comparisons of prediction residuals data, statistical tests, and silvicultural and physiological considerations. One model is proposed as adequate for leaf area estimation of E. globulus plantation trees. This model contains four parameters and independent variables that quantify stem diameter, crown size, and stand density.