To celebrate its 75th anniversary, the Experimental Station of Arid Zones (EEZA-CSIC) of Almeria has organized a photographic exhibition to show the peculiarities of the Tabernas Desert and other places and species studied by this research center. A montage with two of my photos has been chosen as the main image of the exhibition. Moricandia arvensis is a plant showing a superb phenotypic change between the spring and summer forms. It clearly illustrates the phenotypic plasticity of this species that inhabit dry areas in the South East of the Iberian Peninsula.
The exhibition has been open to the public between November 15, 2022, and January 31, 2023, at the Museo Casa de la Ciencia in Seville. It can also be visited at this link.
Phenotypic plasticity is the ability of a genotype to produce different phenotypes in response to changes in the environment. This is an essential property of living beings but its role in adaptation and acclimatization to environmental changes is not yet fully known.
As part of a truly multidisciplinary team of researchers from the University of Granada, the Experimental Station of Arid Zones (CSIC) and the Universities of Vigo, Pablo Olavide and Rey Juan Carlos, we have just published an article in the top-ranking journal Nature Communications demonstrating experimentally, both in natural conditions and in the laboratory, the phenotypic plasticity of the flowers of a plant species living in semi-arid environments.
In spring, this species – the crucifer Moricandia arvensis – produces large, lilac-colored, UV-reflecting flowers in the shape of a cross. These flowers attract mainly large, long-tongued bees as pollinators. However, unlike most coexisting species, M. arvensis maintains flowering during the dry, hot summer of the western Mediterranean. This is due to its plasticity in key vegetative traits, including photosynthetic traits, that adjust its metabolism to these extreme temperatures and water deficit conditions. The summer’s high temperatures and longer light hours trigger changes in the expression of more than 625 genes in the flower that lead to these plants to produce different radical flowers. Whereas in spring flowers were large and cross-shaped, in summer they are small and rounded; whereas they were lilac and reflected UV, in summer they are white and absorb UV. These summer flowers attract a different set of pollinators composed of more generalist species. This change in the pollinator set (the pollination niche) allows this plant to reproduce successfully under the challenging summer conditions. Phenotypic plasticity for flower, vegetative, and photosynthetic traits seems to allow M. arvensis to cope with anthropogenic disturbances and climate change.
Gómez JM, Perfectti F, Armas C, Narbona E, González-Megías A, Navarro L, DeSoto L, Torices R (2020). Within-individual phenotypic plasticity in flowers fosters pollination niche shift. Nature Communications 11:4019 https://doi.org/10.1038/s41467-020-17875-1
Project MORE: Phenotypic plasticity as a evolutionary driver in Moricandia
In this project, we analyze the genetic basis of the phenotypic plasticity (PP) in some species of genus Moricandia (Brassicaceae), how it expresses in functional and floral traits, and its importance to understanding the ecology and evolution of this plant genus.
Four species inhabit the Iberian Peninsula: three endemic (M. rytidocarpoides, M. foetida, M. moricandioides) and one circum-Mediterranean (M. arvensis). This last species occurs in agricultural, ruderal, and disturbed habitats from south and east of the peninsula, M. moricandioides occurs in semi-deserts from eastern Spain, and the other two species are narrow-endemic desert species from SE Spain. The three Spanish species bloom during a short period during late winter or spring, whereas M. arvensis has an extended flowering spanning from late winter to summer and even autumn. We think that these differences in distribution and flowering phenology are a consequence, at least partially, of the phenotypic plasticity in functional traits displayed by M. arvensis. We also think that an effect of this functional plasticity is the presence of phenotypic plasticity in floral traits and pollination niches.
Moricandia arvensis, contrasting with the other congeneric species, exhibits ample plasticity in floral traits. Whereas spring flowers are large, cross-shaped, and lilac -similar to those of M. moricandioides-, summer flowers are small, rounded, and white -similar to those of the two desert species-. We will determine the genetic basis of this plasticity by studying the effect of environmental factors in gene expression and analyzing regulatory gene networks. We will also explore the impact of these factors in the phenotypic expression by quantifying the reaction norms of floral traits in the field and in experimental conditions.
Flowers from Moricandia arvensis from the same individual maintained in two different climatic conditions
This phenological plasticity in floral traits may entail that the same plant interacts with different pollinator assemblages during different periods. We will test this idea by comparing the spring and summer pollination niches.
We are using environmental niche modeling to test that the niche of M. arvensis is broader and more diverse than the other congeners’ niche. This larger niche width may be a consequence of M. arvensis modulating its photosynthetic metabolism during different periods.
We think that phenotypic plasticity has played a pivotal role in the adaptation of some Moricandia species to desert conditions. This process could have led to phenotypic divergence among populations adapted to different conditions, favoring the establishment of reproductive barriers and eventually giving rise to plasticity-mediated speciation. Our study will gather valuable information to test this fundamental idea.
The coordinated project “Plasticidad fenotípica como motor evolutivo en Moricandia” (MORE) has been funded by the Ministry of Science and Innovation (Project CGL2017-86626) and consists of two sub-projects:
MOREeco
“Evolutionary and functional ecology of phenotypic plasticity in the genus Moricandia.”
PIs: José María Gómez and Cristina Armas (Experimental Station of Arid Zones, CSIC)
MOREgen
“Evolutionary and functional genetics of phenotypic plasticity in the genus Moricandia.”
PI: Francisco Perfectti (University of Granada)
Publications:
Gómez JM, Perfectti F, Armas C, Narbona E, González-Megías A, Navarro L, DeSoto L, Torices R. 2020. Within-individual phenotypic plasticity in flowers fosters pollination niche shift. Nature Communications 11: 4019 BLOG
We present in this paper a molecular phylogeny of the genus Moricandia (Brassicaceae). We have found that a Spanish population previously ascribed to Rytidocarpus moricandioides is indeed a Moricandia species, and we propose to name it as M. rytidocarpoides sp. nov. In addition, M. foleyi appeared outside the Moricandia lineage but within the genus Eruca. Therefore, M. foleyi should be excluded from the genus Moricandia and be ascribed to the genus Eruca. Read more
