PHYSICAL AND CHEMICAL DEFENSES OF Cenostigma pyramidale (FABACEAE): A PIONEER SPECIES IN SUCCESSIONAL CAATINGA AREAS

Abstract

Cenostigma pyramidale, a pioneer species presents in all different successional stage (early, intermediate and late) of fifteen natural regeneration areas of Caatinga after land used changed and abandonment was used to investigates the morphological and physiological attributes that are very important to xeromorphic conditions as against herbivories. Leaf samples were collected to evaluate the percentage of the herbivory and index of sclerophylly. Anatomy, histochemistry, total phenolic content, epicuticular wax load, and n-alkanes profile were also performed. The results showed an inverse relationship between the percentage of herbivory and the index of sclerophylly. The leaves showed typical morphological and anatomical characteristics of xeric environments plants such as uniseriate epidermis and trichomes. Furthermore, it was also noticed a decrease in the overall thickness and the tissues according to the advancement of the successional stages. The histochemical revealed the presence of lipidic substances coating the epidermal layers, phenolics compounds stored in secretory structures, and starch in the mesophyll. The concentration of phenolics compounds indicating the difference from health leaves of plants between different stages of regeneration, but no difference when they were herbivored. The amount of cuticle wax did not change significantly with the successional stage. The profile of n-alkanes was characterized by the predominance of nonacosane (C29) and hentriacontane (C31). The C29 content decreases with the advancement of the successional stage, while the C31 content increases. All those attributes have a role to protect the plants to acclimate to the various environmental conditions of Caatinga.

Divergent effects of leaf‐cutting ant herbivory and soil engineering on the reproductive success of plants in a Caatinga dry forest

“…Limited water availability, as observed during the study period, may thus result in flower and fruit production of plants with ant herbivory not differing from control plants. Although C. pyramidale can tolerate water stress (Ribeiro et al, 2021) and is even recognised as a disturbance‐adapted species (Ribeiro et al, 2015; Ribeiro‐Neto et al, 2016), it has been observed that open and desiccated conditions due to increased aridity combined with human disturbance negatively affect the reproduction of the closely related and co‐occurring species Cenostigma microphyllum (Oliveira et al, 2022). Thus, it seems that even disturbance‐adapted species can have their reproductive success negatively affected in scenarios of very severe environmental conditions.…”

A sucessão florestal e a arquitetura vegetal influenciam a herbivoria em Cenostigma pyramidale em Floresta Tropical Sazonal Seca?

“…Presente nos três estádios sucessionais da floresta tropical seca deste estudo e sendo uma espécie de grande importância ecológica (Falcão et al, 2015(Falcão et al, , 2017Ribeiro et al, 2021), a leguminosa Cenostigma pyramidale (Tul.) E. Gagnon & G. P. Lewis foi a planta-modelo para o teste das hipóteses deste estudo, uma vez que apresenta ampla distribuição e estava presente em todos os estádios sucessionais (Cabral et al, 2013).…”

“…As maiores taxas de área foliar registradas em indivíduos presentes no estádio intermediário também foram observadas por Magalhães (2011). No entanto, dois anos depois, após período de seca prolongada, Ribeiro et al (2021) não encontram diferenças significativas nas taxas de herbivoria entre os estádios, provavelmente devido ao aumento da densidade de herbívoros em todos os estádios após chuvas, pela disponibilidade do recurso planta após um período atípico. Segundo Cabral et al ( 2013), a maior abundância de C. pyramidale no estádio intermediário indicam um maior valor de importância desta espécie neste ambiente.…”

“…Segundo Ribeiro et al (2021), as folhas expostas à alta incidência luminosa são mais resistentes e possuem maior teor de compostos fenólicos que as de folhas de sombra. Não houve a análise dos compostos fenólicos para este estudo, porém, a mesma autora, utilizando as mesmas áreas e planta, registrou para esta espécie uma concentração de compostos fenólicos nas folhas herbivoradas com tendência semelhante às taxas de herbivoria encontradas neste estudo, sugerindo que o ataque de herbívoros induz a planta a produzir estes compostos.…”

Growth and metabolism of <i>Pityrocarpa moniliformis</i> Benth. seedlings under water deficit

“…Economic growth in the northeastern semi-arid region of Brazil is mainly based on the exploitation of natural resources, which has led to the degradation of ecosystems (GONG et al, 2016). This process is intensified by climate change, which can cause severe damage to plants, especially those related to abiotic stresses, which interfere with plant development (GOMES et al, 2020;RIBEIRO et al, 2021).…”