Biology subjects

Riella, V.

Publications and source records attributed to Riella, V..

3 recordsLinked to original sources

bioRxiv2026

Effects of spectral light quality on growth, photosynthetic pigments and bioactive compounds in Brassicaceae microgreens

LED spectral composition is an important tool for improving the growth and nutritional quality of microgreens cultivated in controlled environments. This study evaluated the effects of three LED light treatments on growth, morphology, pigments, primary metabolites, phenolic composition, and antioxidant capacity in arugula (Eruca sativa), mustard (Brassica juncea), and radish (Raphanus sativus) microgreens. Microgreens were cultivated under controlled environmental conditions and exposed to broad-spectrum white (W), blue-enriched white (WB), and red-enriched white (R) light at a photosynthetic photon flux density of 200 micromol/m2/s. Light quality did not affect yield in any species. However, R increased cotyledon area in arugula by 50 to 60% and promoted hypocotyl elongation in both arugula and radish, whereas W resulted in the longest hypocotyls in mustard. Photosynthetic pigment composition responded differently among species. In mustard, WB increased the chlorophyll a/b ratio (1.12 to 1.18), whereas lutein concentration decreased from 7.06 to 4.20 mg 100 g/FW. Primary metabolism also responded to light treatments in a species-dependent manner. In mustard, W increased glucose (0.43 vs. 0.26 and 0.29 g 100 g/ FW) and fructose (0.33 vs. 0.20 and 0.22 g 100 g/ FW) concentrations compared with WB and R. Organic acid composition was more responsive to light treatments in radish, with higher concentrations under R. Phenolic metabolism also responded in a species-dependent manner. In mustard, W increased total phenolic content to 0.25 mg GAE g/FW compared with 0.15 mg GAE g/FW under WB and R, and ABTS antioxidant capacity to 1.17 mg TE g/FW compared with 0.74 and 0.75 mg TE g/FW under WB and R, respectively. Individual phenolic compounds were also affected by light treatments, particularly in arugula and mustard. These findings demonstrate that the effects of LED spectral composition on microgreen quality are highly species-dependent. Therefore, LED light spectra should be optimized according to the target species and the desired quality attributes rather than applying a single lighting strategy to all Brassicaceae microgreens.

plant biology↗

bioRxiv2025

Long-term surveillance suggests multiple hybridization events by nuclear reassortment and accelerated intercontinental spread of wheat yellow rust

O_LIEvolutionary forces affecting crop pathogens, including hybridization and long-distance dispersal (LDD), may have strong implications for food security and sustainable plant disease control at global scales. However, consolidated evidence is often lacking due to absence of consistent pathogen surveys beyond national capacities. C_LIO_LIOur study documents world-wide connectivity between populations of Puccinia striiformis, causing yellow rust on cereals and grasses, when analysing 3240 pathogen samples collected in 41 countries on six continents from 2009-2023. Our analyses revealed twelve cases of inter-continental spread of Puccinia striiformis, including seven cases with major impact on disease epidemics in recipient areas. C_LIO_LISomatic hybridization by nuclear reassortment between co-existing multi-locus genotypes (MLGs) on a common host was the most plausible mechanism for the emergence of three novel clonal groups of global relevance, first detected in Europe. Subsequently, onwards spread to South America and Australia was observed. Several high-impact incursions from South Asia into East Africa were also observed, including a genotype with a dramatic impact on wheat breeding programs of global relevance. C_LIO_LIOur study stresses an urgent need for coordinated crop pathogens monitoring across borders. Only global efforts will enable prevention and control of pathogens that represent major challenges for food security at regional and global scales. C_LI

evolutionary biology↗

bioRxiv2023

New races with wider virulence indicate local evolution of Puccinia striiformis f. sp. tritici in South America

Wheat yellow (stripe) rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most devastating diseases of wheat worldwide. Pst populations are composed of multiple genetic groups, each carrying one or more races characterized by different avirulence/virulence combinations. Since the severe epidemics in 2017, yellow rust has become the most economically important wheat foliar disease in Uruguay. Evolution of virulence was investigated based on genotyping and race typing of a representative set of 27 Pst isolates collected from wheat fields in Uruguay between 2017 and 2021. Three genetic groups were identified, i.e., PstS7, PstS10 and PstS13, the latter being the most prevalent. Two races previously reported in Europe, Warrior (PstS7) and Benchmark (PstS10), were detected in four and two isolates, respectively. A third race known as Triticale2015 (PstS13), first detected in Europe in 2015 and in Argentina in 2017, was detected at several locations. Additional virulence to Yr3, Yr17, Yr25, Yr27 or Yr32 was detected in three new race variants within PstS13. The identification of these new races, which have not been reported outside South America, provides strong evidence of the local evolution of virulence in Pst during the recent epidemic years.

pathology↗