ABSTRACT Several abiotic factors, such as water availability, significantly affect the development of forest species found in the understory. This research aimed to evaluate morphophysiological characteristics in plants of Erythroxylum pauferrense submitted to different water regimes. The experiment was developed in a greenhouse at the Federal University of Paraíba, Campus II, Areia, Paraíba, Brazil. The experimental design was in randomized blocks, with five water treatments [100%, 80%, 60%, 40% and 20% of the pot capacity (PC)] and four replications. Growth attributes, morphofunctional aspects, gas exchange, chlorophyll fluorescence and chlorophyll indices were evaluated. The data were submitted for analysis of variance, and in cases of significance, polynomial regression analyses were performed. The plants of Erythroxylum pauferrense submitted to 100% and 80% water levels of the PC present greater development and morphophysiological performance. In comparison, the evaluated parameters were significantly reduced in the regime of greater water stress (20% of the PC). Thus, the water regime of 80% of PC is the most recommended for producing seedlings of Erythroxylum pauferrense, promoting greater growth and significant changes in morphofunctional aspects, gas exchange, chlorophyll fluorescence and chlorophyll indexes.

RESUMO Vários fatores abióticos, como a disponibilidade de água, afetam significativamente o desenvolvimento das espécies florestais encontradas no sub-bosque. Esta pesquisa teve como objetivo avaliar características morfofisiológicas em plantas de Erythroxylum pauferrense submetidas a diferentes regimes hídricos. O experimento foi desenvolvido em casa de vegetação na Universidade Federal da Paraíba, Campus II, Areia, Paraíba, Brasil. O delineamento experimental foi em blocos ao acaso, com cinco tratamentos hídricos [100%, 80%, 60%, 40% e 20% da capacidade do vaso (PC)] e quatro repetições. Foram avaliados atributos de crescimento, aspectos morfofuncionais, trocas gasosas, fluorescência da clorofila e índices de clorofila. Os dados foram submetidos à análise de variância e, nos casos de significância, análises de regressão polinomial. As plantas de Erythroxylum pauferrense submetidas a regimes hídricos de 100% e 80% da PC apresentam maior desenvolvimento e desempenho morfofisiológico. Em comparação, os parâmetros avaliados foram significativamente reduzidos no regime de maior estresse hídrico (20% da PC). Assim, o regime hídrico de 80% de PC é o mais recomendado para produção de mudas de Erythroxylum pauferrense, promovendo maior crescimento e alterações significativas nos aspectos morfofuncionais, trocas gasosas, fluorescência da clorofila e índices de clorofila.

ABSTRACT Basil (Ocimum gratissimum - Lamiaceae), is a sub-shrub plant species with great economic importance for several regions, and studies on its growth, physiology, and reproduction become needed. The aimed research was to obtain a regression equation to estimate leaf area of O. gratissimum. 250 basil leaves were collected and the linear dimensions (length and width) and real leaf area of each leaf were measured. From these data, the products between length and width, length and length were calculated. Equations were obtained using regression models: linear, linear without intercept, quadratic, cubic, power, and exponential. The best equation was selected based on determination coefficient, Pearson’s correlation coefficient, Willmott’s agreement index and CS index, Akaike information criterion, mean absolute error and root mean square error. All equations proposed using the product between length and width (LW) can be used to predict the leaf area of O. gratissimum. However, the equation LA=0.54*LW1.03 (power model) is the most recommended to estimate the leaf area of this species.

RESUMO A luz solar influencia diretamente no desenvolvimento das espécies florestais, afetando os atributos de crescimento e fisiologia das plantas. Dentre essas espécies, Erythroxylum pauferrense Plowman é considerada uma espécie rara, pois sua distribuição é restrita apenas ao estado da Paraíba. Diante disso, são necessários estudos que busquem avaliar a adaptação, desenvolvimento e propagação da espécie em diferentes condições ambientais. Este trabalho teve como objetivo avaliar os aspectos morfofisiológicos de mudas de Erythroxylum pauferrense submetidas a diferentes níveis de sombreamento. O experimento foi conduzido em casa de vegetação, em delineamento inteiramente casualizado, com cinco tratamentos (0, 30, 50, 70 e 90% de sombreamento) e oito repetições. Foram avaliadas as características de crescimento, atributos morfofuncionais, trocas gasosas, fluorescência da clorofila (Chl) a e teor de Chl. Os dados foram submetidos à análise de variância seguida de análise de regressão polinomial. Os resultados mostraram que as plantas cultivadas sob 30 a 50% de sombreamento apresentaram maior altura da planta, diâmetro do caule, taxa de crescimento absoluto para altura da planta, massa seca da folha, massa seca do caule, massa seca total, índice de qualidade de Dickson, área foliar e índice de área foliar, bem como a taxa de assimilação líquida de CO2, condutância estomática, transpiração, eficiência instantânea do uso da água e conteúdo de Chl a, b e a+b. Portanto, níveis de 30 a 50% de sombreamento são os mais recomendados para a produção de mudas de Erythroxylum pauferrense. Recomenda-se o uso de Erythroxylum pauferrense para reflorestar o sub-bosque em áreas perturbadas nos Brejos de Altitude e a produção em larga escala de mudas em níveis de 30 a 50% de sombreamento.

ABSTRACT Sunlight directly influences on the development of forest species by affecting the attributes of plant growth and physiology. Among these species, Erythroxylum pauferrense Plowman is considered a rare species, as its distribution is restricted only to the state of Paraíba. Therefore, studies are needed that seek to evaluate the adaptation, development and propagation of the species under different environmental conditions. This study aimed to evaluate morphophysiological aspects of Erythroxylum pauferrense seedlings submitted to different levels of shading. The experiment was carried out under greenhouse condition in a completely randomized design with five treatments (0, 30, 50, 70, and 90% shading) and eight replicates. Growth characteristics, morphofunctional attributes, gas exchange, chlorophyll (Chl) a fluorescence, and Chl content were evaluated. Data were submitted to analysis of variance followed by polynomial regression analysis. Results showed that plants grown under 30 to 50% shading showed higher plant height, stem diameter, absolute growth rate for plant height, leaf dry mass, stem dry mass, total dry mass, Dickson’s quality index, leaf area, and leaf area index, as well as net assimilation rate of CO2, stomatal conductance, transpiration, instantaneous water use efficiency, and Chl a, b, and a+b contents. Therefore, levels from 30 to 50% shading are the most recommended for the production of Erythroxylum pauferrense seedlings. We recommend using Erythroxylum pauferrense to reforest the understory in disturbed areas in Brejos de Altitude and large-scale production of seedlings under intermediate levels of shading.

Abstract: Erythroxylum pauferrense Plowman is an understory species native to Brazil, with great importance in the conservation of genetic resources and is used as a food source for animals in the regions where the species occurs. The species is currently listed in category EN (endangered). The objective of this work was to evaluate the effect of different substrates on the emergence and initial growth of E. pauferrense. The experiment was carried out in a protected environment, belonging to the Plant Ecology Laboratory of the Federal University of Paraíba, Areia-PB, Brazil. The substrates used were: sand; sand + vermiculite in the proportion of 1:1, 3:1 and 1:3; vegetal land; vegetal land + sand in the proportion of 1:1, 3:1 and 1:3; vegetal land + vermiculite in the proportion of 1:1, 3:1 and 1:3; vermiculite; Bioplant®; and Bioplant® + sand in a ratio of 1:1, 3:1 and 1:3. The experimental design was completely randomized, with 16 treatments (substrates) and four replications of 25 seeds. The percentage of emergence, first count, speed index, mean time, mean speed and relative emergency frequency were evaluated. The vermiculite substrate provided the best results for carrying out the emergence and vigor tests of E. pauferrense seedlings, being the most suitable substrate to initial growth seedlings of the species.

Abstract Thus, the objective of the research was to evaluate the initial growth and development of seedlings under Platymiscium floribundum at different levels of luminosity. The experimental design was completely randomized in a 4 x 10 factorial scheme (four levels of shade: full sun, 50%, 65% and 80% with ten replications per treatment. The height, number of leaves was evaluated monthly. At the end of the experiment at 180 days, leaf dry matter, stems, roots, and dry matter. In addition, measurements were made of the variables related to gas exchange and plant anatomy of leaves. The results obtained were observed higher growth and developed satisfactorily at full sun), without presenting morphological changes. For the gas exchange did not differ statistically. It is concluded that the initial growth of P. floribundum seedlings was superior in the light level in full sun, providing favorable conditions for their development.

Resumo A determinação da área foliar é de fundamental importância em estudos ecofisiológicos que buscam entender a relação planta-ambiente. Objetivou-se com esta pesquisa determinar uma equação alométrica que permita estimar a área foliar de Mesosphaerum suaveolens a partir de medidas lineares do limbo foliar (comprimento e/ou largura). Coletaram-se 900 limbos foliares aleatórios de diferentes formas e tamanhos, em uma área de Caatinga antropizada, localizada no município de Santa Luzia, estado da Paraíba, nordeste do Brasil. Para a construção das equações alométricas utilizaram-se os seguintes modelos de regressão: linear, linear sem intercepto, quadrático, cúbico, potência e exponencial. O modelo linear sem intercepto utilizando o produto entre comprimento e largura (C.L) foi o mais indicado para estimar a área foliar de M. suaveolens, com maior coeficiente de determinação (R2) e índice de concordância de Willmott (d), menor erro absoluto médio (MAE), critério de informação de Akaike (AIC) e raiz do quadrado médio do erro (RQME), e índice BIAS mais próximo de zero (R2 = 0,9971; d = 0,9989; MAE = 0,422; AIC = 2094,69; RQME = 0,770; BIAS = -0,0105). A área foliar de M. suaveolens pode ser estimada satisfatoriamente pela equação AF = 0,6787*(C.L).

Abstract The determination of leaf area is of fundamental importance in ecophysiological studies that seek to understand the plant-environment relationship. The objective of this research was to determine an allometric equation to estimate the leaf area of Mesosphaerum suaveolens from linear measures of leaf blade (length and/or width). There were collected 900 random leaf limbs of different shapes and sizes, in an anthropic area of caatinga, located in the municipality of Santa Luzia, state of Paraíba, Northeast of Brazil. For the construction of the allometric equations the following regression models were used: linear, linear without intercept, quadratic, cubic, power, and exponential. The linear model without intercept using the product between length and width (C.L) was the most recommended to estimate the leaf area of M. suaveolens, with greater coefficient of determination (R2) and Willmott concordance index (d), lesser mean absolute error (MAE), Akaike information criterion (AIC) and root-mean-square error (RQME), and the closer the BIAS ratio is to zero (R2 = 0.9971; d = 0.9989; MAE = 0.422; AIC = 2094.69; RQME = 0.770; BIAS = -0.0105). The leaf area of M. suaveolens can be estimated satisfactorily by equation AF = 0.6787*(C.L).

Abstract Studies of leaf surface are important for the ecophysiological context. We tested 12 allometric equations to estimate the leaf area of the endemic species Erythroxylum pauferrense Plowman, using different morphometric measurements (n = 600). The analysis of variance (p < 0.001), determination coefficient (R2adj), standard error of estimates (Sxy), and graphical interpretation of the dispersion of errors were used to select the models. The residual bias was estimated through the confidence interval using t-Student distribution (p = 0.01). Simple linear equations (Ŷ = 0.0244 + 0.7204 × CxL) and power functions (Ŷ = 0.7279 × CxL0.9971) were validated from an independent sample of leaves, confirming their accuracy. The results are important to guide actions of conservation of the endemic species.

Abstract Estimating leaf area is essential to evaluate vegetal growth. Our study sought to obtain statistical models to allow the leaf area estimation of Palicourea racemosa, considering its length (L) and width (W). For such purpose, we collected 200 leaves of this species in the State Park Mata do Pau-Ferro, in the municipality of Areia, Paraíba, Northeast of Brazil. The regression models used were: linear, linear without intercept, power and exponential. The choice of the best equation was based on the values of the coefficient of determination (R2), root mean square error (RMSE), Akaike information criterion (AIC), Willmott concordance index (d) and BIAS ratio. All linear and power models may be used to measure the P. racemosa leaf area; however, the power model LA = 0 . 609 * ( L . W ) 0 . 995 is the most recommended to estimate this species’ leaf area.

ABSTRACT Erythroxylum simonisis an understory species found in Northeast Brazil. Due to its shaded habitat,E. simonisis subjected to seasonal oscillations of the environment, to which it must respond ecophysiologically. The objective of this study was to evaluate the effects of seasonality on the ecophysiology ofE. simonis in a fragment of Seasonal Semideciduous Forest. Leaf area index, visible sky fraction and photosynthetically active radiation were measured for 10 individuals during the dry and rainy seasons. Soil moisture, temperature and monthly precipitation were measured, as well as photosynthetic rate, stomatal conductance, internal CO2concentration, transpiration, instantaneous water use efficiency, instantaneous carboxylation efficiency and chlorophyll content. Ecophysiological variables were correlated with environmental variables, with a greater association of rainfall and soil moisture with stomatal conductance, transpiration and photosynthetic rate, indicating that water availability has an effect on the ecophysiology ofE. simonis. With the exception of instantaneous carboxylation efficiency, gas exchange exhibited significant differences among the months studied, with the highest values being for months with greater water availability, thus showing that the ecophysiology of the species responds to seasonal changes throughout the year.

ABSTRACT This research aimed to determine an equation to estimate the leaf area of Erythroxylum simonis using the length and width of leaf blades. Two hundred leaf blades of this species were collected in Mata do Pau-Ferro, a State Park located in Areia, PB, Brazil. Regression analyses were used to determine the estimation equations. The linear, linear without intercept, quadratic, cubic, power and exponential statistical models were used. The criteria used for model selection were based on an examination of the coefficient of determination, the Akaike information criterion and standard error of the estimate. All the equations presented can be used to estimate the leaf area of E. simonis. From a practical point of view, the linear regression equation without intercept involving the product between length and width is recommended, using the equation Y=0.6426*LW, which corresponds to 64.26% of the product between length and width, with a coefficient of determination of 0.9936.

RESUMO Cryptostegia madagascariensis Bojer ex Decne. é uma espécie de porte arbustivo capaz de formar maciços populacionais em diversos nichos da caatinga e ecossistemas associados, sobretudo nos sítios mais úmidos, podendo alterar as características da vegetação nativa, causando o desaparecimento das espécies autóctones. Este estudo teve como objetivo identificar os impactos causados pela invasora sobre a composição florística e a estrutura do componente arbustivo-arbóreo. Foram selecionadas três áreas de investigação, sendo denominadas de Ambiente I - área com forte intensidade de invasão, Ambiente II - área de transição entre o I e o III (média intensidade) e o Ambiente III - área com baixa intensidade de invasão. Para o inventário dessas áreas foi empregado o método de amostragem por pontos (Método dos Quadrantes), sendo considerados adultos os indivíduos com diâmetro ao nível do solo (DNS) maior ou igual a 3 cm e altura maior ou igual a 1 m. Para a avaliação da estrutura foram analisados os parâmetros fitossociológicos convencionais, além dos índices de Diversidade, de Equabilidade e de Impacto Ambiental de Exóticas (IIAE). No Ambiente I, Cryptostegia madagascariensis foi responsável por 82% da densidade, enquanto que nos Ambientes II e III, a densidade da espécie foi bastante reduzida (14,2% e 9,6%, respectivamente). A diversidade, pelo Índice de Shannon-Weiner, foi baixa para o Ambiente I (0,85) e maior para os Ambientes II e III (2,67 e 2,50, respectivamente). Os resultados demostram que Cryptostegia madagascariensis afeta drasticamente a diversidade e a estrutura das comunidades invadidas, ocasionando perda da biodiversidade autóctone da caatinga.

ABSTRACT Cryptostegia madagascariensis Bojer ex Decne. is a shrubby species capable of forming populational massifs in several niches of caatinga and its related ecosystems, especially in the most humid sites, that may change the characteristics of native vegetation, triggering the disappearance of autochthonous species. This study aimed to identify the impacts caused by the invader on the floristic composition and the structure of the shrub-arboreal component. Three areas of investigation were selected, they were termed by: Ambience I - area with a high intensity of invasion, Ambience II - the transition area between I and III (medium intensity), and Ambience III - area with a low intensity of invasion. For the inventory of those areas, it was used the point-centered sampling method (Quarter Method), considering adults those plants that presented the diameter at ground level (DGL) greater than or equal to 3 cm, and height greater than or equal to 1m. For the evaluation of the structure the conventional phytosociological parameters were analyzed, beyond indices of Diversity, Equitability and Environmental Impact of Exotics (IEIE). In the Ambience, I Cryptostegia madagascariensis was responsible for 82% of density, while in the Ambiences II and III, the density of the species was severally reduced (14.2% and 9.6%, respectively). The diversity, according to the Shannon-Weiner index, was low for the Ambience I (0.85) and higher for the Ambiences II and III (2.67 e 2.50, respectively). Results demonstrate that Cryptostegia madagascariensis affects severely the diversity and the structure of invaded communities, causing loss in the autochthonal biodiversity of caatinga.

Abstract In the 1970s, the social impacts of protected areas (PAs) began to be widely recognized as conservationist thinking and human rights evolved to an acceptance that conservation can be achieved in collaboration with traditional communities. However, such a 'human face' given to conservation is still not present in some 21st century PAs: Catimbau National Park - CNP (Northeast Brazil) is a strict protection park which does not allow people residing inside its borders. Thirteen years after its creation, people are still confused about the monetary compensations and displacements strategies. In this study, a review of the bibliography concerning the CNP is performed and a proposal is made to change the current park classification from National Park to Natural Monument, allowing for private areas and their residents, providing that their use of its natural resources is compatible with the conservation objectives stipulated.

Resumen En los años 70, los impactos sociales de las áreas protegidas comenzó a ser reconocido como el pensamiento conservacionista y los derechos humanos han evolucionado a la comprensión de que la conservación se puede lograr con la colaboración de las comunidades tradicionales. Este "rostro humano" permanece ausente en algunas áreas protegidas en el siglo 21: el Parque Nacional Catimbau (PNC - noreste de Brasil), es un parque estrictamente protegido, lo que significa que la residencia de población en su límites no está permitido. Trece años después de su creación, la gente continúa confundidos acerca de la compensación monetaria y las estrategias de desplazamiento. Este estudio, realizó una revisión de la literatura en la PNC y propone cambiar la actual clasificación de Parque Nacional para Monumento Natural, lo que permite la existencia de áreas particulares asegurando que es posible conciliar los objetivos de unidad con el uso de los recursos naturales.

The temporal expression of gene sor1 and the inhibitory effect of Sorghum bicolor L. Moench against weeds were studied by semiquantitative polymerase chain reaction and intercropping management, respectively. To quantify sor1 expression, seeds were sown in pots and RNA was collected from the roots at 5, 10, 15, 20 and 30 days after emergence (DAE). In the inhibition assay, cotton and three weeds were evaluated during single cropping and during intercropping with S. bicolor. The assay was completely randomized, with eight replications. We found early expression of sor1 in most S. bicolor accessions by 5 DAE, and a gradual reduction thereafter. Only one of the accessions showed sor1 expression up to 30 DAE. In the inhibition assay, the most significant effects were related to the dry matter production (shoots and roots) of the weeds Cenchrus echinatus and Cynodon dactylon. The intercropping of cotton and S. bicolor had no apparent deleterious effects.

Procedeu-se a um estudo em plântulas de mangabeira, com o objetivo de avaliar a germinação, crescimento inicial e relações hídricas em casa de vegetação. O delineamento experimental utilizado foi o inteiramente casualizado, com 50 repetições e três tipos de substratos: areia autoclavada, solo natural coletado em pomar espontâneo da espécie e uma mistura de húmus, areia e terriço vegetal na proporção de 2: 4: 4 (v/v/v). Verificaram-se a porcentagem de germinação, índice de velocidade de emergência (IVG), altura das plântulas, número de folhas, temperatura foliar (Tf), transpiração (E) e resistência difusiva (Rs). Foram mensuradas também a temperatura (Tar), umidade relativa (UR) e a radiação fotossinteticamente ativa (PAR). Os maiores percentuais de germinação e IVG ocorreram em areia autoclavada. A altura e o número de folhas não foram influenciados pelos substratos. Foram verificadas diferenças significativas entre os tratamentos para E e Rs. Folhas de plantas cultivadas em solo natural transpiraram mais do que as da mistura (9,59 e 2,59 mmol.m-2.s-1, respectivamente), sendo que ambas diferiram daquelas cultivadas em areia autoclavada (4,63 mmol.m-2.s-1). A Rs em folhas no substrato areia foi de 2,2 s.cm-1, enquanto, nas folhas em solo natural, esse valor foi de 0,9 s.cm-1. Verificou-se efeito inverso e significativo para as correlações entre a Tf e E, e positivo entre Tf e Rs. Os efeitos de E x Rs foram inversos e altamente significativos para todos os tratamentos estudados. A Tf, E e Rs, bem como a altura das plântulas e o número de folhas não foram influenciados pela Tar, UR e PAR.

This study was carried out in greenhouse aiming to evaluate the germination, initial growth and water relations in mangaba seedlings. The experimental design was a completely randomized with fifty replicates and three substrates: autoclaved sand, local soil of the plants native region and a mixed of humus, sand and vegetal soil (2:4:4, v/v/v). The following variables were studied: germination and emergence velocity (IVG) rates, seedling height, number of leaves, leaf temperature (LT), transpiration (E) and diffusive resistance (Rs). Also some climate variables were measured: air temperature (Tar), relative humidity (UR) and photosynthetic active radiation (PAR). The larger values of germination and IVG were observed in autoclaved sand substrate. Both plant height and number of leaves hadn't been influenced by substrates. There were significant differences among treatments in relation to E and Rs. Leaves of seedlings cultivated in native soil have transpired more than mixed substrate (9.59 and 2.59 mmol.m-2.s-1, respectively). Leaves cultivated in autoclaved sand showed intermediate value (4.63 mmol.m-2.s-1). There were variations on Rs of leaves for sand substrate and for native soil substrate (2.2 and 0.9 s.cm-1, respectively). Inverse and significant effect for correlations among LT and E was verified. Positive effect was observed among LT and Rs. Effects of E x Rs were inverse and significant for all treatments. LT, E and Rs, as well as seedling height and number of leaves were not influenced by Tar, UR and PAR.