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1.
Sci Rep ; 10(1): 9431, 2020 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-32523106

RESUMO

Growth behavior of different species under different habitats can be studied by comparing the production of biomass, plasticity index and relative competitive interaction. However, these functional traits of invasive species received rare consideration for determining the invasion success of invasive species at wetlands. Here, we examined the effect of water depth at 5 cm and 15 cm (static and fluctuated) with different nutrient concentrations (full-strength (n1), 1/4-strength (n2) and 1/8-strength (n3) Hoagland solution) on functional traits of invasive Wedelia trilobata and its congener native Wedelia chinensis under mono and mixed culture. Water depth of 5 cm with any of the nutrient treatments (n1, n2 and n3) significantly restrained the photosynthesis, leaf nitrogen and photosynthetic nitrogen use efficiency (PNUE) of both W. trilobata and W. chinensis. While, increase in the water depth to 15 cm with low nutrient treatment (n3) reduced more of biomass of W. chinensis under mixed culture. However, relative competition interaction (RCI) was recorded positive for W. trilobata and seemingly W. trilobata benefited more from RCI under high-fluctuated water depth at 15 cm in mixed culture. Therefore, higher PNUE, more competitive ability and higher plasticity may contribute to the invasiveness of W. trilobata in wetlands.


Assuntos
Wedelia/crescimento & desenvolvimento , Wedelia/metabolismo , Asteraceae/crescimento & desenvolvimento , Asteraceae/metabolismo , Evolução Biológica , Biomassa , Ecossistema , Hidrologia , Espécies Introduzidas/tendências , Nitrogênio/metabolismo , Fotossíntese , Água , Wedelia/genética , Áreas Alagadas
2.
Ecol Evol ; 10(2): 832-842, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32015847

RESUMO

The distribution of invasive and native species in wetlands is determined by hydrological conditions; whereas conditions such as water depth fluctuations, variations in the nutrient concentrations are expected to affect the growth and physiological traits of plants. For the assessment of such effects, we conduct greenhouse experiment with three factors; 1) water depth of 5 cm and 15 cm (static and fluctuated); 2) three levels of nutrient concentrations (i) full-strength Hoagland solution (N1), (ii) »-strength Hoagland solution (N2), and (iii) 1/8-strength Hoagland solution (N3); and 3) species, invasive Wedelia trilobata (L.) and its congener, native Wedelia chinensis (Osbeck.) under mono and mixed culture. Water depth of 5 cm combined with any of the nutrient treatments significantly restrained the photosynthesis, intracellular CO2 concentration and leaf chlorophyll of both W. trilobata and W. chinensis. Increase in the water depth to 15 cm with low-nutrient treatment N3 did not sustain the physiological traits of W. chinensis under mono and mixed planting. A great loss was noted in the growth of W. chinensis at 15 cm static and fluctuated water depth with low-nutrient treatment (N3) and under mixed culture. In addition, water depth fluctuations with both low- and high-nutrient treatments significantly affected the root-shoot ratio, relative growth rate, and interspecific interaction among these two species. W. trilobata benefited more from competitive interaction index (CII) under fluctuated water depth at 15 cm with high nutrients, and the value of CII was clearly positive. Therefore, higher competitive ability may contribute to the invasiveness of W. trilobata in wetlands.

3.
Biosci. j. (Online) ; 33(5): 1219-1229, sept./oct. 2017. tab
Artigo em Inglês | LILACS | ID: biblio-966289

RESUMO

In this study, two okra cultivars, Chinese green and Chinese red were used to assess the water status and growth parameters subjected to salt stress by adding NaCl and CaCl2 with same proportion in Hoagland culture solution at levels of 0%, 0.6%, 1.2%, 1.8% and re-watering at levels of 0.6-0%, 1.2-0.6%, 1.8-1.2%. The measured water potential and physiological capacitance values were used to calculate leaf tensity. Salt stress significantly reduced growth and water status parameters. Chinese green showed more reduction as compared to Chinese red but at 1.8% salt stress reduction of both cultivars were almost same. Re-watering had given a positive response for both cultivars to recover from higher salt stress. Dry weight, physiological capacitance, leaf tensity and salts concentration levels models gave predicting re-watering levels in percentage, also gave values of dilute irrigation point for Chinese red 9.05 or 10.00 ds m-1 and Chinese green 6.67 or 5.66 ds m-1. At resulted dilution points, plants of both cultivars were under high salt stress, which emphasized the need to re-water or dilution of salts for the survival of plants. The most effective predicting re-watering level and dilute irrigation point of both cultivars were found in same regime, so these models findings were very credible and meaningful. Higher dilute irrigation value of Chinese red indicates its more tolerance ability than Chinese green. Model's equations also gave direct irrigation point of Chinese red 1.32 or 1.62 ds m-1 and Chinese green 2.07 or 0.38 ds m- 1. It was concluded that predicting re-watering levels, dilute and direct irrigation point help to get maximum production using saline water resources.


Neste estudo, foram utilizados dois cultivares de quiabo, verde chinês e vermelho chinês para avaliar o estado da água e parâmetros de crescimento submetidos a estresse salino, adicionando NaCl e CaCl2 com a mesma proporção em solução de cultura de Hoagland a níveis de 0%, 0,6%, 1,2% , 1,8% e re-irrigação a níveis de 0,6-0%, 1,2-0,6%, 1,8-1,2%. O potencial de água medido e os valores de capacitância fisiológica foram utilizados para calcular a tensão das folhas. O estresse com sal reduziu significativamente os parâmetros de crescimento e de estado da água. O verde chinês mostrou mais redução em comparação ao vermelho chinês, mas em 1,8% a redução do estresse salino de ambas as cultivares foi quase a mesma. Re-rega tinha dado uma resposta positiva para ambas as cultivares para recuperar de maior sal estresse. Os valores de peso seco, capacitância fisiológica, tensão da folha e níveis de concentração de sais mostraram predizer níveis de irrigação em porcentagem, também apresentaram valores de ponto de irrigação diluído para vermelho chinês 9,05 ou 10,00 ds m-1 e verde chinês 6,67 ou 5,66 ds m-1. Nos pontos de diluição resultantes, as plantas de ambas as cultivares estavam sob alto estresse salino, o que enfatizou a necessidade de re-água ou diluição de sais para a sobrevivência das plantas. O nível de irrigação mais eficiente e o ponto de irrigação diluído de ambas as cultivares foram encontrados no mesmo regime, portanto, esses resultados foram muito confiáveis e significativos. Maior valor de irrigação diluída de vermelho chinês indica a sua capacidade de tolerância mais do que verde chinês. As equações do modelo também deram ponto de irrigação direta de vermelho chinês 1,32 ou 1,62 ds m-1 e verde chinês 2,07 ou 0,38 ds m-1. Concluiu-se que a previsão dos níveis de rega, o ponto de irrigação diluído e direto ajudam a obter a máxima produção usando recursos hídricos salinos.


Assuntos
Produção Agrícola , Abelmoschus/crescimento & desenvolvimento
4.
Indian J Otolaryngol Head Neck Surg ; 67(4): 434-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26693466

RESUMO

The paranasal sinuses are air filled spaces. The process of development of paranasal sinuses begins prenatally. The agenesis of paranasal sinuses in an unusual clinical condition and that is mainly confined to the frontal sinus unilaterally. Combined aplasia of multiple sinuses is extremely rare along with hypoplasia of other sinuses. Agenesis of sphenoid sinus is also rare in incidence. We report a case of a 54 years old female, who presented with complains of persistent headache with nasal blockage and found to have combined aplasia of bilateral frontal and sphenoid sinus with hypoplasia of bilateral maxillary and ethmoid sinus with unusual age of presentation. The findings were confirmed on non-contrast computed tomography scan of paranasal sinuses.

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