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1.
Ecology ; 105(6): e4308, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38629131

RESUMO

The recent availability of open-access repositories of functional traits has revolutionized trait-based approaches in ecology and evolution. Nevertheless, the underrepresentation of tropical regions and lineages remains a pervasive bias in plant functional trait databases, which constrains large-scale assessments of plant ecology, evolution, and biogeography. Here, we present MelastomaTRAITs 1.0, a comprehensive and updatable database of functional traits for the pantropical Melastomataceae, the ninth-largest angiosperm family with 177 genera and more than 5800 species. Melastomataceae encompass species with a wide diversity of growth forms (herbs, shrubs, trees, epiphytes, and woody climbers), habitats (including tropical forests, savannas, grasslands, and wetlands from sea level to montane areas above the treeline), ecological strategies (from pioneer, edge-adapted and invasive species to shade-tolerant understory species), geographic distribution (from microendemic to continental-wide distribution), reproductive, pollination, and seed dispersal systems. MelastomaTRAITs builds on 581 references, such as taxonomic monographs, ecological research, and unpublished data, and includes four whole-plant traits, six leaf traits, 11 flower traits, 18 fruit traits, and 27 seed traits for 2520 species distributed in 144 genera across all 21 tribes. Most data come from the Neotropics where the family is most species-rich. Miconieae (the largest tribe) contains the highest number of trait records (49.6%) and species (41.1%) records. The trait types with the most information in the database were whole-plant traits, flowers, and leaf traits. With the breadth of functional traits recorded, our database helps to fill a gap in information for tropical plants and will significantly improve our capacity for large-scale trait-based syntheses across levels of organization, plant-animal interactions, regeneration ecology, and thereby support conservation and restoration programs. There are no copyright restrictions on the dataset; please cite this data paper when reusing the data.


Assuntos
Bases de Dados Factuais , Melastomataceae , Ecossistema , Melastomataceae/fisiologia , Melastomataceae/genética
2.
Heliyon ; 9(7): e17834, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37501953

RESUMO

The estimative of the leaf area using a nondestructive method is paramount for successive evaluations in the same plant with precision and speed, not requiring high-cost equipment. Thus, the objective of this work was to construct models to estimate leaf area using artificial neural network models (ANN) and regression and to compare which model is the most effective model for predicting leaf area in sesame culture. A total of 11,000 leaves of four sesame cultivars were collected. Then, the length (L) and leaf width (W), and the actual leaf area (LA) were quantified. For the ANN model, the parameters of the length and width of the leaf were used as input variables of the network, with hidden layers and leaf area as the desired output parameter. For the linear regression models, leaf dimensions were considered independent variables, and the actual leaf area was the dependent variable. The criteria for choosing the best models were: the lowest root of the mean squared error (RMSE), mean absolute error (MAE), and absolute mean percentage error (MAPE), and higher coefficients of determination (R2). Among the linear regression models, the equation yˆ=0.515+0.584*LW was considered the most indicated to estimate the leaf area of the sesame. In modeling with ANNs, the best results were found for model 2-3-1, with two input variables (L and W), three hidden variables, and an output variable (LA). The ANN model was more accurate than the regression models, recording the lowest errors and higher R2 in the training phase (RMSE: 0.0040; MAE: 0.0027; MAPE: 0.0587; and R2: 0.9834) and in the test phase (RMSE: 0.0106; MAE: 0.0029; MAPE: 0.0611; and R2: 0.9828). Thus, the ANN method is the most indicated and accurate for predicting the leaf area of the sesame.

3.
Am J Bot ; 110(8): e16211, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37459470

RESUMO

PREMISE: Variation in fruit and seed traits could originate from selection pressures exerted by frugivores or other ecological factors (adaptive hypotheses) and developmental constraints (by-product hypotheses) or chance. METHODS: We evaluated fruit and leaf traits for nearly 850 plant species from a rainforest in Tinigua Park, Colombia. Through a series of linear regressions controlling for the phylogenetic signal of the traits (minimum N = 542), we tested (1) whether the allometry between seed width and length depends on seed dispersal system (Mazer and Wheelwright's adaptive hypothesis of allometry for species dispersed in the guts of animals = endozoochory) and (2) whether fruit length is associated with leaf length (i.e., Herrera's by-product hypothesis derived from the assumption that both organs develop from homologous structures). RESULTS: We found a strong negative allometric association between seed width and length for seeds of endozoochorous species, as expected; but also, for anemochorous species. We found a positive relationship between fruit and leaf length, but this relationship was not evident for zoochorous species. Fruit size was highly correlated with seed size. CONCLUSIONS: The allometry between seed length and width varied among dispersal systems, supporting that fruit and seed morphology has been modified by interactions with frugivores and by the possibility to rotate for some wind dispersed species. We found some support for the hypothesis on developmental constraints because fruit and leaf size were positively correlated, but the predictive power of the relationship was low (10-15%).


PREMISA: La variación en los rasgos de frutos y semillas de las plantas podría tener su origen en las presiones de selección ejercidas por los frugívoros u otros factores ecológicos (hipótesis adaptativas), así como en limitaciones del desarrollo (hipótesis de subproductos) o en el azar. MÉTODOS: Nosotros evaluamos rasgos de frutos y hojas en cerca de 850 especies de plantas de un bosque húmedo tropical en el Parque Nacional Natural Tinigua, Colombia. Usando una serie de regresiones lineales que controlan por la señal filogenética de dichos rasgos (mínimo N = 542), nosotros probamos (1) si la alometría entre el ancho y largo de la semilla depende del sistema de dispersión de la semilla (i.e., hipótesis adaptativa de Mazer y Wheelwright; en la que se espera una alometría negativa para especies dispersadas por endozoocoria) y (2) si el largo del fruto está asociado con el largo de la hoja (i.e., la hipótesis del subproducto de Herrera derivada de la suposición de que ambos órganos se desarrollan a partir de estructuras homólogas). RESULTADOS: Nosotros encontramos una fuerte asociación alométrica negativa entre el ancho y el largo de las semillas para las semillas de las especies endozoócoras, como era de esperar; pero también, para las especies anemócoras. Nosotros también hallamos una relación positiva entre el largo del fruto y de la hoja, pero esta relación no fue evidente para las especies endozoócoras. Detectamos que el tamaño del fruto esta altamente correlacionado con el tamaño de la semilla. CONCLUSIONES: La alometría entre el largo y el ancho de la semilla varió entre sistemas de dispersión, lo que sugiere que la morfología de frutos y semillas ha sido moldeada por interacciones con frugívoros en el caso de las semillas endozoócoras y por la posibilidad de rotar para algunas especies dispersadas por el viento. Aunque el poder predictivo de la relación entre el tamaño del fruto y de la hoja fue bajo (10-15%), nosotros encontramos un apoyo moderado a la hipótesis sobre las limitaciones del desarrollo, ya que el tamaño del fruto y de la hoja estaban correlacionados positivamente.


Assuntos
Frutas , Dispersão de Sementes , Animais , Frutas/anatomia & histologia , Floresta Úmida , Filogenia , Sementes/anatomia & histologia , Folhas de Planta
4.
Data Brief ; 46: 108784, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36569540

RESUMO

This data paper summarizes the data of a first survey of terrestrial ferns at Mashpi Biodiversity Reserve, an Ecuadorian Chocó forest relict, one of the most biodiverse areas in the world. We established 10 permanent plots of 400 m2 distributed in two elevational levels (800 and 1000 m a.s.l.) to register all species per plot and the abundance per species. In addition, we measured two morphological leaf functional traits of the species. We include a file with three tables, the first one includes a species list with scientific names and vouchers. The second one includes the abundance of each species per plot. The third one contains measurements of the leaf length and leaf thickness of several leaf samples of 28 species, representing the leaf functional traits of the species. This article also includes a table with coordinates and elevations of the plots and five figures with information about the number of genus and species per family, geographic location of plots and, the methodology for data collection. These data can be useful for plant ecologists to assess future changes of fern species composition and leaf functional traits of ferns caused by climate change and other threats at the study area.

5.
Ciênc. rural (Online) ; 53(11): e20220432, 2023. tab, ilus, graf
Artigo em Inglês | VETINDEX | ID: biblio-1427324

RESUMO

Leaf area of dried Flue-cured tobacco is a reflection of climate and stage of growth of fresh tobacco in field; it also serves as the foundation for calculating a number of significant physical properties of tobacco. So the purpose of this paper was to establish a model to estimate the leaf area of dried Flue-cured tobacco in China from linear dimensions. Three Hundred eight tobacco leaves from different growing area and stalk position were sampled randomly and separated for model selection among linear, proportional and power model type and external evaluation individually. Results showed that there was a significant and strong correlation between leaf area and length×width , The equation LA = 0.495(L×W), where LA is the leaf area and L×W is the product of leaf length and width, was optimum and adequate for the estimation of leaf area of dried tobacco in China examined by Fisher's test, Akaike delta information criterion (AIC) and Bayesian information criterion (BIC). Growing area and stalk position had minor effect on the parameter before (L×W). The equation can sufficiently predict the area of leaf for external evaluation.


A área foliar do tabaco curado pelo Flue seco é um reflexo do clima e do estágio de crescimento do tabaco fresco no campo; também serve como base para o cálculo de várias propriedades físicas significativas do tabaco. Portanto, o objetivo deste artigo foi estabelecer um modelo para estimar a área foliar do tabaco curado por Flue seco na China a partir de dimensões lineares. Foram amostradas aleatoriamente 308 folhas de tabaco de diferentes áreas de cultivo e posição do colmo e separadas para seleção de modelos entre tipo linear, proporcional e de potência e avaliação externa individualmente. Os resultados mostraram que houve uma correlação significativa e forte entre área foliar e comprimento×largura. A equação LA = 0,495 (L×W), em que LA é a área foliar e L×W é o produto do comprimento e largura da folha, ótima e adequada para a estimativa da área foliar de tabaco seco na China examinada pelo teste de Fisher, critério de informação delta de Akaike (AIC) e critério de informação bayesiana (BIC). A área de cultivo e a posição do caule tiveram efeito menor no parâmetro antes (C×L). A equação pode prever suficientemente a área da folha para avaliação externa.


Assuntos
Nicotiana/anatomia & histologia , Nicotiana/crescimento & desenvolvimento , Modelos Lineares , Desenvolvimento Vegetal
6.
Rev. biol. trop ; Rev. biol. trop;68(2)jun. 2020.
Artigo em Inglês | LILACS, SaludCR | ID: biblio-1507684

RESUMO

Introduction: Light stress is an important factor limiting the biomass yield while combining forage production with crops or forestry. Guinea grass is a widely adapted perennial fodder grass. The species exhibits high degree of variation for morphology, adaptation and biomass yield. Objective: Since there is a need in identifying shade adapted forage grasses for the expanding area under agroforestry/silvipastures, the present investigation took the task of understanding how the morphologically distinct genotypes of guinea grass respond under different shaded intensities. Methods: In the present study, forty-four genotypes related with the shade response were studied in varying shading conditions (pure sunlight, 25, 50 and 75 % shade) created artificially. Results: Based on green and dry matter yields ranking, the genotype IG 01-98 performed the best followed by genotypes IG 01-92, IG 97-5, IG 97-6 and IG 01-89 in decreasing order. Particularly, IG 01-93 was identified as the best performing under 50 % shading conditions. On the other hand, most of the top ranking genotypes performed well both under open and up to 50 % of shade. Morphologically, these genotypes were taller and possessed longer and broader leaves. Under shaded conditions (over 50 %), leaf length and width showed an increasing trend compared to open conditions. Also, chlorophyll content increased with shading intensity. Conclusions: Most of the genotypes collected from the southern Indian humid tropical environment with early flowering nature were tolerant to shade. Differential genotypic response was observed for biomass yield and yield attributes under shade. The study established appreciable variability for shade tolerance among genotypes.


Introducción: El estrés leve es un factor importante que limita el rendimiento de la biomasa al tiempo que combina laproducción forrajera con los cultivos o la silvicultura. El zacate guinea es una planta de forraje perenne ampliamente adaptada. La especie presenta un alto grado de variación en su morfología, adaptación y rendimiento de biomasa. Objetivo: Como existe la necesidad de la identificación de pastos forrajeros adaptados a la sombra para el área de expansión bajo agroforestería /silvicultura, la presente investigación se realizó para entender cómo los genotipos morfológicamente distintos al zacate guinea responden a diferentes intensidades de sombra. Métodos: Se estudiaron 44 genotipos y su respuesta a los niveles de sombra: luz solar pura y 25, 50 y 75 % de sombra (creados artificialmente). Resultados: Basado en la clasificación de rendimientos demateria verde y seca, el genotipo IG 01-98 fue el mejor, seguido de los genotipos IG 01-92, IG 97-5, IG 97-6 e IG 01-89 en orden decreciente. Por su parte, el IG 01-93 fue identificado como el de mayor rendimiento bajo el 50 % de condición de sombra. La mayoría de los genotipos de primer nivel tuvieron un buen desempeño, tanto bajo sombra abierta como al 50 %. Morfológicamente, estos genotipos fueron más altos y poseían hojas más largas y más anchas. En condiciones de sombra, de más del 50 %, la longitud y ancho de la hoja mostraron una tendencia creciente en comparación con la condición abierta. El contenido de clorofila aumentó con la intensidad de la sombra. Conclusiones: La mayoría de los genotipos recolectados al sur de la India en un ambiente tropical húmedo y tienen una floración temprana, fueron tolerantes a la sombra. Se observó una respuesta genotípica diferencial para los atributos de rendimiento y rendimiento de biomasa bajo sombra. El estudio mostró la existencia de una variabilidad apreciable para la tolerancia a la sombra entre los genotipos.


Assuntos
Biomassa , Poaceae/classificação , Poaceae/crescimento & desenvolvimento , Índia
7.
Ci. Rural ; 37(5): 1458-1461, 2007.
Artigo em Inglês | VETINDEX | ID: vti-15062

RESUMO

This research was aimed at establishing regression equations to estimate black pepper (Piper nigrum) leaf area based on linear leaf measures. Different black pepper varieties where growth on the field, four different size leaves were collected per plant with a total of 52 leaves to establish the regression equation and 28 to validate the equation for each variety (Bragantina, Laçará, Guajarina e Cingapura). Leaf midrib length (LML), maximum leaf broad width (MLBW) and leaf area (LA) were measured. Pearson"s linear correlation coefficients were determined between observed and predicted measures with the observed LA, besides estimating the linear regression equation for each variety. The equations best-fitted to estimate LA based on circumscript rectangle were: 1) LA = 2.2689 + 0.6900 x LML x MLBW; 2) LA = 1.6402 + 0.6816 x LML x MLBW; 3) LA = 1.4942 + 0.6215 x LML x MLBW and 4) LA = 0.7467 + 0.6735 x LML x MLBW, for Bragantina, Laçará, Guajarina and Cingapura varieties respectively. For all equations predicted values had high correlation coefficient with observed values thus showing that these equations must be variety specific and that they are appropriate for black pepper leaf area estimative.(AU)


O objetivo deste trabalho foi estabelecer equações de regressão para estimar a área foliar de diferentes variedades de pimenta-do-reino (Piper nigrum) cultivadas no campo, a partir de medidas lineares de folhas. Foram coletadas quatro folhas por planta, de tamanhos diferentes, totalizando 52 folhas, para estabelecer a equação de regressão e 28 para validar a equação para cada variedade (Bragantina, Laçará, Guajarina e Cingapura). Procederam-se às medições do comprimento da nervura central (LML), da maior largura do limbo foliar (MLBW) e da área foliar (LA). Determinaram-se os coeficientes de correlação linear de Pearson entre as medidas mensuráveis e preditas com a LA observada, além de estimarem-se as equações de regressão linear para cada variedade. As equações que melhor se ajustaram para estimar LA com base no retângulo circunscrito foram: LA = 2.2689 + 0.6900 x LML x MLBW, para Bragantina; LA = 1.6402 + 0.6816 x LML x MLBW, para Laçará; LA = 1.4942 + 0.6215 x LML x MLBW, para Guajarina e LA = 0.7467 + 0.6735 x LML x MLBW, para Cingapura, para as quais os valores preditos apresentaram elevada correlação com os valores observados, indicando que as equações devem ser específicas para cada variedade e que são coerentes para estimar a área foliar de pimenta do reino.(AU)


Assuntos
Piper nigrum , Estatística como Assunto
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