Plant adaptation to problems of Mediterranean soils: case studies using the model Arabidopsis thaliana and relatives.

Salinity and high carbonate contents are major problems for crop production on soils in the Mediterranean area. Saline soils reduce yield due to ion toxicity, osmotic stress and bad soil structure. On carbonate soils, major constraints are the low availability of certain essential nutrients, especially Fe, Zn, and P, the excess of bicarbonate and, occasionally boron, as well as the soil compactation and the shallow root systems. Our current research focuses on the mechanisms underlying tolerance to these soil-derived stress factors using natural populations of the model plant Arabidopsis thaliana and other related Brassicaceae species. Our approach uses common-garden field experiments, as well as laboratory studies for the identification of contrasting phenotypes and physiological processes related to sensitivity and tolerance. Crossing of extreme parentals followed by BSA sequencing, RNA seq and GWAS techniques are being used to identify responsible key genes. As A. thaliana natural populations can adapt only to moderate salinity and carbonate levels, other Brassicaceae are explored. Germplasm from the Mediterranean area, but also from extremely high saline and alkaline sites in Iran is used for this purpose.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

The unseen world beneath our feet: Heliyon Soil Science. Exploring the cutting-edge techniques and ambitious goals of modern soil science

In the face of climate change, ecosystem destruction, desertification, and increasing food demand, soil conservation is crucial for ensuring the sustainability of life on Earth. The Soil Section of Heliyon aims to be a platform for basic and applied soil science research, emphasizing the central role of soils and their interactions with human activities. This editorial highlights recent research trends in soil science, including the evolving definition of soil, the multifunctionality of soils and their biodiversity, soil degradation and erosion, the role of soil microflora, advancements in soil mapping techniques, global change and the carbon cycle, soil health, the relationship between soil and buildings, and the importance of considering soil quality in land use planning and policies. The Heliyon Soil Science section seeks to publish scientifically accurate and valuable research that explores the diverse functions of soil and their significance in sustainable land-use systems

Phytoremediation : principles and perspectives

Acute and diffuse contamination of soil and water by heavy metals and metalloids cause wide, environmental and social concern. Among the techniques used to cleanup affected sites, phytoremediation has recently emerged as a new, cost-effective, environment-friendly alternative. After a short introduction to the types of plant-based cleanup techniques, this review focuses on metal hyperaccumulator plants and their potential use in phytoextraction technology.Hi ha una preocupació social i científica creixent per la contaminació ambiental, aguda i difusa, dels sòls i de l'aigua per metalls pesants. Entre la diversitat de tècniques disponibles per a la neteja dels llocs afectats, la fitoremediació ha emergit recentment com una nova alternativa, efectiva de costos i sostenible ambientalment. Després d'una breu introducció als diferents tipus de tècniques basades en les plantes, aquesta revisió se centra principalment en les plantes hiperacumuladores de metalls i considera el seu potencial per a les tecnologies de fitoextracció

Aspectos fisiológicos de la fitotoxicidad por manganeso en phaeseolus vulgaris

Tesis doctoral, Univ. Complutense de Madrid, 1980.Fac. de FarmaciaTRUEProQuestpu

Sugar beet profits from intercropping with wheat both under optimum and deficient phosphorus supply

An experiment was conducted with wheat and sugar beet as monocrop and intercrop under low or adequate phosphorus supply. Dry matter production of shoot and roots were decreased in wheat while increased in sugar beet under intercrop conditions. Photosynthesis rate was diminished under intercrop conditions in wheat while elevated in sugar beet concomitant with reduction of transpiration rate and higher water use efficiency in the latter species. Phosphorus, potassium and iron contents were also lower in intercrop wheat while increased in sugar beet. The same effect of intercropping on biomass and nutrients uptake was observed in the short term hydroponic experiment. Interestingly, three root parameters including length, soluble carbohydrates and activity of secretory acid phosphatase that are characteristics for phosphorus-deficient plants were enhanced in both species by intercropping irrespective the phosphorus supply level. These data suggested an interspecific interaction beyond the different nutrient acquisition capacity in the intercrop pots.V raziskavi je bil opravljen poskus s pšenico in sladkorno peso v čisti kulturi in medsetvi v razmerah primerne in pomankljive preskrbe s fosforjem. V razmerah medsetve sta se biomasi korenin in poganjkov zmanšali pri pšenici a povečali pri sladkorni pesi. Podobno se je pri pšenici v medsetvi zmanjšala fotosinteza in povečala pri sladkorni pesi s hkratnim zmanjšanjem transpiracije in večjoučinkovitostjo izrabe vode. Pravtako so bile vsebnost fosforja, kalija in železa manjše pri pšenici v medsetvi in večje pri sladkorni pesi. Podoben učinek medsetve na biomaso in vsebnost hranil je bil opazen v kratkotrajnem hidroponskem poskusu. Zanimivo je, da so se neglede na preskrbo s fosforjem v medsetvi pri obeh vrstah povečali parametri korenin kot so njihova dolžina, vsebnost topnih ogljikovih hidratov in aktivnost izločenih kislih fosfataz, kar je značilnost rastlin, ki rastejo v pomanjkanju fosforja. Podatki nakazujejo na medvrstne interakcije, ki presegajo razlike v sposobnosti privzema hranil v lončnem poskusu z medsetvijo

El parasitisme : un estil de vida avantatjós

Des del Departament de Biologia Animal, de Biologia Vegetal i Ecologia de la Universitat Autònoma de Barcelona (UAB) s'han analitzat els efectes de la contaminació per metalls pesants en plantes de l'àrea Mediterrània. Dins del previst, els sòls contaminats esdevenen terres poc fèrtils, però l'article següent ens presenta un tercer personatge en discòrdia que surt indemne de tota aquesta situació: la planta hemiparàsita o paràsita, un tipus de vegetal que s'aprofita de l'aigua i dels nutrients que li proporciona la planta hostatgera. Sembla ser que en tot aquest procés de parasitisme, la planta hostatgera actua com a filtre descontaminador evitant que els metalls pesants afectin el paràsit

Hiperacumulación de metales : ¿una ventaja para la planta y para el hombre?

La hiperacumulación es la capacidad que tienen algunas plantas para concentrar metales en sus tejidos a niveles muy por encima de los normales sin presentar síntomas de toxicidad. Estas plantas hiperacumuladoras han desarrollado mecanismos internos de tolerancia a la toxicidad por metales. Esta peculiaridad las hace útiles para el hombre como herramienta en las nuevas tecnologías de fitoremediación. Sin embargo, ¿cual es el beneficio de esta hiperacumulación de metales para la propia planta? Se han propuesto distintas hipótesis entre las que destaca la ventaja adaptativa de estas plantas frente al estrés biótico. Esta propuesta es una de las más atractivas para explicar la "razón de ser" de estas especies hiperacumuladoras. En este artículo se plantean dos aspectos esenciales: los mecanismos de acumulación y tolerancia de las plantas a la toxicidad por metales y si para la planta la hiperacumulación es realmente una ventaja adaptativa.Metal hyperaccumulation is the ability of some plants to accumulate metals in their tissues to levels above normal concentrations without any toxicity symptoms. Hyperaccumulating plants have evolved internal tolerance mechanisms to metal toxicity. This peculiarity makes them very useful for us as a tool for new phytoremediation technologies. Nevertheless, which is the benefit of metal hyperaccumulation for the plant itself? Different hypothesis have been proposed but the most remarkable is an adaptive advantage of these plants against biotic stress. This proposal is one of the most attractive to account for the "reason to be" of these metal hyperaccumulating species. In this paper two essential aspects are pointed out: the tolerance mechanisms of metal accumulation in these plants and whether metal hyperaccumulation is really an adaptive advantag

Genome-Wide Association Study Reveals Key Genes for Differential Lead Accumulation and Tolerance in Natural Arabidopsis thaliana Accessions

Soil contamination by lead (Pb) has become one of the major ecological threats to the environment. Understanding the mechanisms of Pb transport and deposition in plants is of great importance to achieve a global Pb reduction. We exposed a collection of 360 Arabidopsis thaliana natural accessions to a Pb-polluted soil. Germination rates, growth, and leaf Pb concentrations showed extensive variation among accessions. These phenotypic data were subjected to genome wide association studies (GWAs) and we found a significant association on chromosome 1 for low leaf Pb accumulation. Genes associated with significant SNP markers were evaluated and we selected EXTENSIN18 (EXT18) and TLC (TRAM-LAG1-CLN8) as candidates for having a role in Pb homeostasis. Six Pb-tolerant accessions, three of them exhibiting low leaf Pb content, and three of them with high leaf Pb content; two Pb-sensitive accessions; two knockout T-DNA lines of GWAs candidate genes (ext18, tlc); and Col-0 were screened under control and high-Pb conditions. The relative expression of EXT18, TLC, and other genes described for being involved in Pb tolerance was also evaluated. Analysis of Darwinian fitness, root and leaf ionome, and TEM images revealed that Pb-tolerant accessions employ two opposing strategies: (1) low translocation of Pb and its accumulation into root cell walls and vacuoles, or (2) high translocation of Pb and its efflux to inactive organelles or intracellular spaces. Plants using the first strategy exhibited higher expression of EXT18 and HMA3, thicker root cell walls and Pb vacuolar sequestration, suggesting that these genes may contribute to the deposition of Pb in the roots. On the other hand, plants translocating high amounts of Pb showed upregulation of TLC and ABC transporters, indicating that these plants were able to properly efflux Pb in the aerial tissues. We conclude that EXT18 and TLC upregulation enhances Pb tolerance promoting its sequestration: EXT18 favors the thickening of the cell walls improving Pb accumulation in roots and decreasing its toxicity, while TLC facilitates the formation of dictyosome vesicles and the Pb encapsulation in leaves. These findings are relevant for the design of phytoremediation strategies and environment restoration

A Role for Zinc in Plant Defense Against Pathogens and Herbivores

Pests and diseases pose a threat to food security, which is nowadays aggravated by climate change and globalization. In this context, agricultural policies demand innovative approaches to more effectively manage resources and overcome the ecological issues raised by intensive farming. Optimization of plant mineral nutrition is a sustainable approach to ameliorate crop health and yield. Zinc is a micronutrient essential for all living organisms with a key role in growth, development, and defense. Competition for Zn affects the outcome of the host-attacker interaction in both plant and animal systems. In this review, we provide a clear framework of the different strategies involving low and high Zn concentrations launched by plants to fight their enemies. After briefly introducing the most relevant macro- and micronutrients for plant defense, the functions of Zn in plant protection are summarized with special emphasis on superoxide dismutases (SODs) and zinc finger proteins. Following, we cover recent meaningful studies identifying Zn-related passive and active mechanisms for plant protection. Finally, Zn-based strategies evolved by pathogens and pests to counteract plant defenses are discussed