Diversity of non‐structural carbohydrates in grasses (Poaceae) from Brazil

Abstract

Non‐structural carbohydrates (NSC) are the primary energy available for growth and dry‐mass production in forage grasses. They are also associated with tolerance to environmental stresses, including drought. Soluble carbohydrates, especially fructans of temperate forage grasses, have been extensively studied; however, little is known about NSC of tropical grasses. These plants are abundant in the Cerrado, a savanna‐like vegetation with a definite seasonality in rainfall distribution. Such an environment presents an ideal condition for the occurrence of fructans. However, the present analysis of carbohydrates in aerial parts of twenty‐four tropical grass species, mainly from the Panicoideae subfamily in the Cerrado, shows a distinctively different NSC profile when compared with temperate grasses. Free glucose and starch are common NSC found in most plant organs. However, free fructose and sucrose‐based oligosaccharides were only found in very low amounts. Sucrose was detected in higher amounts only in stems. A linear series of malto‐oligosaccharides was found in leaf blades, sheaths and stems of most of the Cerrado grasses, except for those from the Andropogoneae tribe. These results indicate a diversity of regulatory pathways of NSC metabolism in tropical forage grasses from the Cerrado.

Fructan dynamics in the underground organs of Chresta exsucca (Asteraceae), a dry season flowering species

“…Water content of underground organs varies among species of Asteraceae, as well as fructan content (Tertuliano & Figueiredo-Ribeiro 1993), because storage of resources depends on the relative distribution of tissues in a specific organ (Moraes et al 2013). During dry periods, water maintenance in vegetative organs depends on the interaction of different factors including the presence of osmoprotectants that regulate osmotic adjustment (Singh et al 2015).…”

Biología del pasto rosado Melinis repens (Willd.) e implicaciones para su aprovechamiento o control

“…Otros reportes de invasiones en el mundo incluyen Zimbawe (16) , Argentina, Bolivia, Brasil, Paraguay, Uruguay (17) y el resto de América del sur y el Caribe (18) . En México también es considerada entre las especies invasoras de alto impacto a la biodiversidad (19) ; actualmente se encuentra en todos los estados del país (20) .…”

“…Other reports of invasions in the world include Zimbabwe (16) , Argentina, Bolivia, Brazil, Paraguay, Uruguay (17) and the rest of South America and the Caribbean (18) . In Mexico it is also considered among the invasive species with high impact on biodiversity (19) ; currently it is found in all the states of the country (20) .…”

A high‐throughput method using Ultra‐Performance Liquid Chromatography to determine water‐soluble carbohydrate concentrations in pasture plants

“…For example, irrigation treatment significantly reduced WSC concentration of millet but had no significant effect on WSC concentration of a hybrid brassica species (Jacobs et al., ). Water‐soluble carbohydrates have been associated with tolerance to environmental stress, including drought (Moraes, Chatterton, Harrison, Filgueiras, & Figueiredo‐Ribeiro, ). A further objective of this study was to investigate the effect of irrigation on the total WSC and individual sugar concentrations of nine different summer forage crops.…”

“…Conversely, WSC analysis using liquid chromatography provides not only a total WSC concentration, but also individual WSC components. The individual WSC components are quantified using various sugar standards, thereby producing more accurate results (Moraes et al., ). Currently, there are a number of methods using high‐performance liquid chromatography (HPLC) for analysing WSC in forages (Chatterton, Harrison, Thornley, & Draper, ; Kagan, Kirch, Thatcher, Teutsch, & Pleasant, ) While HPLC methods provide accurate results, sample throughput is limited by long run times (e.g., 40 min).…”