Effects of light and temperature on isoprene emission at different leaf developmental stages of eschweilera coriacea in central Amazon

Abstract

Isoprene emission from plants accounts for about one third of annual global volatile organic compound emissions. The largest source of isoprene for the global atmosphere is the Amazon Basin. This study aimed to identify and quantify the isoprene emission and photosynthesis at different levels of light intensity and leaf temperature, in three phenological phases (young mature leaf, old mature leaf and senescent leaf ) of Eschweilera coriacea (Matamatá verdadeira), the species with the widest distribution in the central Amazon. In situ photosynthesis and isoprene emission measurements showed that young mature leaf had the highest rates at all light intensities and leaf temperatures. Additionally, it was observed that isoprene emission capacity (E s ) changed considerably over different leaf ages. This suggests that aging leads to a reduction of both leaf photosynthetic activity and isoprene production and emission. The algorithm of Guenther et al. (1999) provided good fits to the data when incident light was varied, however differences among E S of all leaf ages influenced on quantic yield predicted by model. When leaf temperature was varied, algorithm prediction was not satisfactory for temperature higher than ~40 °C; this could be because our data did not show isoprene temperature optimum up to 45 °C. Our results are consistent with the hypothesis of the isoprene functional role in protecting plants from high temperatures and highlight the need to include leaf phenology effects in isoprene emission models. KEYWORDS: light response curve, temperature response curve, leaf phenology, tropical species.Efeitos da luz e da temperatura sobre a emissão de isopreno em diferentes estádios de desenvolvimento foliar de Eschweilera coriacea na Amazônia Central RESUMO O isopreno emitido pelas plantas corresponde em cerca de um terço das emissões globais de compostos orgânicos voláteis anualmente. A maior fonte de emissão de isopreno para a atmosfera global é a Bacia Amazônica. Este estudo objetivou identificar e quantificar a emissão de isopreno e fotossíntese em diferentes níveis de intensidade de luz e temperatura foliar, em três fases fenológicas (folha madura recente, folha madura tardia e folha senescente) de Eschweilera coriacea (Matamatá verdadeira) -a espécie com maior distribuição na Amazônia central. In situ, as medidas de fotossíntese e emissão de isopreno da folha madura recente apresentaram as maiores taxas em todos os níveis de luz e de temperatura. Adicionalmente, a capacidade de emissão de isopreno (E S ) mudou consideravelmente entre as diferentes idades foliares, sugerindo que o envelhecimento reduz a atividade fotossintética e a produção/emissão de isopreno. O algoritmo de Guenther et al. (1999) demonstrou bom ajuste para a emissão de isopreno em diferentes intensidades de luz, entretanto, diferenças na E S entre as idades foliares influenciaram no rendimento quântico estimado pelo modelo. Em relação à temperatura foliar, a estimativa do algoritmo não foi satisfatória para as temperaturas acima de ~...

Observations of sesquiterpenes and their oxidation products in central Amazonia during the wet and dry seasons

“…6). This is in contrast with typically observed daytime maxima for isoprene and monoterpenes (Alves et al, 2016;Yáñez-Serrano et al, 2015), for which reactive loss is dominated by reaction with OH and with OH / O 3 , respectively (Atkinson, 1997;Kesselmeier and Staudt, 1999), and whose daytime emissions are likely more associated with immediate release following production as a function of solar radiation input (Alves et al, 2014;Bracho-Nuñez et al, 2013;Harley et al, 2004;Jardine et al, 2015;Kuhn, 2002;Kuhn et al, 2004). To better understand the reactive loss of O 3 , the estimated cumulative loss of O 3 by reaction with sesquiterpenes compared to that by reaction with isoprene and monoterpenes is shown for the wet and dry seasons in Figs.…”

Seasonality of isoprenoid emissions from a primary rainforest in central Amazonia

“…show maximum isoprene emission at the upper canopy during the dry-to-wet transition season (Fig. 4a), which is coincident with the period of high abundance of healthy efficient leaves at the canopy top (Nelson et al, 2014) and also coincident with the maximum isoprene emission shown in young mature leaves in the dry-to-wet transition season (Alves et al, 2014). Similarly, higher isoprene emissions during the late dry season have also been related to the increase of active biomass in southern Amazonia (Kesselmeier et al, 2002;Kuhn et al, 2004a, b).…”

Methanol and Isoprene Emissions from the Fast Growing Tropical Pioneer Species <i>Vismia guianensis</i> (Aubl.) Pers. (Hypericaceae) in the central Amazon Forest

“…rapidly expanding leaves have consistently been observed to have higher methanol emissions than mature leaves (Hüve et al, 2007;Nemecek-Marshall et al, 1995). Methanol production is thought to be initiated during pectin demethylation re-actions catalyzed by the enzyme pectin methylesterase (Bai et al, 2014). In this reaction, the hydrolysis of galacturonic acid methyl esters strengthens the cell wall while liberating methanol as a by-product (Hüve et al, 2007;Harley et al, 2007;Bai et al, 2014;Hanson and Roje, 2001).…”

“…Methanol production is thought to be initiated during pectin demethylation re-actions catalyzed by the enzyme pectin methylesterase (Bai et al, 2014). In this reaction, the hydrolysis of galacturonic acid methyl esters strengthens the cell wall while liberating methanol as a by-product (Hüve et al, 2007;Harley et al, 2007;Bai et al, 2014;Hanson and Roje, 2001). High rates of methanol emission may be associated with higher catalytic activity of this enzyme (Galbally and Kirstine, 2002;Hüve et al, 2007).…”