This review provides a wide-ranging assessment of approaches to reduce the impact of heat stress on food crops.
Abstract
To ensure the food security of future generations and to address the challenge ...of the ‘no hunger zone’ proposed by the FAO (Food and Agriculture Organization), crop production must be doubled by 2050, but environmental stresses are counteracting this goal. Heat stress in particular is affecting agricultural crops more frequently and more severely. Since the discovery of the physiological, molecular, and genetic bases of heat stress responses, cultivated plants have become the subject of intense research on how they may avoid or tolerate heat stress by either using natural genetic variation or creating new variation with DNA technologies, mutational breeding, or genome editing. This review reports current understanding of the genetic and molecular bases of heat stress in crops together with recent approaches to creating heat-tolerant varieties. Research is close to a breakthrough of global relevance, breeding plants fitter to face the biggest challenge of our time.
Seasonal bud development in Maakа cherry Lokteva, Anna; Simagin, Vladimir; Frolova, Lyudmila
BIO Web of Conferences,
01/2021, Volume:
38
Journal Article, Conference Proceeding
Peer reviewed
Open access
Wild relatives of fruit plants are an important reserve for introducing certain properties and traits into cultivated plants that significantly expand the range and facilitate the possibility of ...their use, since many wild species are sources of useful properties and traits that are poorly expressed or absent in cultivated species and varieties. One of these types is undoubtedly the Maaka.
Ecological theory suggests that biodiversity has a positive and stabilizing effect on the delivery of ecosystem services. Yet, the impacts of increasing the diversity of cultivated crop species or ...varieties in agroecosystems are still under scrutiny. The available empirical evidence is scattered in scope, agronomic and geographic contexts, and impacts on ecosystem services may depend on the type of diversification strategy used. To robustly assess the effects of crop diversification in agroecosystems, we compiled the results of 95 meta‐analyses integrating 5156 experiments conducted over 84 experimental years and representing more than 54,500 paired observations on 120 crop species in 85 countries. Overall, our synthesis of experimental data from across the globe shows that crop diversification enhances not only crop production (median effect +14%) but also the associated biodiversity (+24%, i.e., the biodiversity of non‐cultivated plants and animals), and several supporting and regulating ecosystem services including water quality (+51%), pest and disease control (+63%) and soil quality (+11%). However, there was substantial variability in the results for each individual ecosystem service between different diversification strategies such as agroforestry, intercropping, cover crops, crop rotation or variety mixtures. Agroforestry is particularly effective in delivering multiple ecosystem services, that is, water regulation and quality, pest and diseases regulation, associated biodiversity, long‐term soil productivity and quality. Variety mixtures, instead, provide the lowest benefits, whereas the other strategies show intermediate results. Our results highlight that while increasing the diversity of cultivated crop species or varieties in agroecosystems represents a very promising strategy for more sustainable land management, contributing to enhanced yields, enhanced biodiversity and ecosystem services, some crop diversification strategies are more effective than others in supporting key ecosystem services.
Impacts of crop diversification on associated biodiversity, provisioning, supporting and regulating ecosystem services. Green ‘+’ icons represent positive impacts, red ‘‐’ icons represent negative impacts, gray circles represent no change. The question marks represent a lack of quantified data. Note that in those cases where the response variable represents a disservice (i.e., greenhouse gas emissions), a negative impact implies an increase in this variable.
La región subtropical húmeda de la provincia de Formosa, en el Nordeste Argentino (Lat. -25,2024130; Long. -58,1212980), presenta una zona de condiciones climáticas para el cultivo de banana (Mussa ...spp.). Los materiales de este cultivo son una mezcla de clones indiferenciados del subgrupo Cavendish. En la selección de material genético adaptado, el primer enfoque fue el análisis sobre las condiciones agroclimáticas en las cuales deberá desarrollarse el material, en producción hacía el 2025–2030. El segundo enfoque fue determinar el grado de polimorfismo fenotípico y molecular existente entre los clones cultivados por Agricultores Familiares. En 2012 se marcaron, en la región subtropical norte de Formosa, 684 clones que mostraron estabilidad de rendimiento. Los criterios de selección fueron resiliencia, ciclo, rendimiento y forma de las manos. Un total de 140 clones seleccionados se implantaron en diseño estadístico aumentado. Con cuatro ciclos de producción, 36 variables (fenológicas, comportamiento a campo y productivas) registradas, marcadores moleculares y datos climáticos se construyó un índice de selección, del cual se desprenden tres Variedades Sintéticas, cada una de ellas conformadas por cuatro Líneas Avanzadas Inta (LAI). En las tres variedades se ha tenido especial atención a las características comerciales, algo esencial para llegar a los mercados. La selección de materiales con características distintas es muy importante en un ambiente variable, las variedades sintéticas nos parecen adecuadas para este tipo de situación, otorgándole mayor resiliencia
Summary
Cannabis (Cannabis sativa L.) is one of the oldest cultivated plants purported to have unique medicinal properties. However, scientific research of cannabis has been restricted by the Single ...Convention on Narcotic Drugs of 1961, an international treaty that prohibits the production and supply of narcotic drugs except under license. Legislation governing cannabis cultivation for research, medicinal and even recreational purposes has been relaxed recently in certain jurisdictions. As a result, there is now potential to accelerate cultivar development of this multi‐use and potentially medically useful plant species by application of modern genomics technologies. Whilst genomics has been pivotal to our understanding of the basic biology and molecular mechanisms controlling key traits in several crop species, much work is needed for cannabis. In this review we provide a comprehensive summary of key cannabis genomics resources and their applications. We also discuss prospective applications of existing and emerging genomics technologies for accelerating the genetic improvement of cannabis.
The global trade of species promotes diverse human activities but also facilitates the introduction of potentially invasive species into new environments. As species ignore national boundaries, ...unilateral national decisions concerning species trade set the stage for transnational species invasion with significant conservation, economic and political consequences.
The need for a coordinated approach to species importation policies is demonstrated by the introduction of two bumblebee species into Chile for crop pollination, despite Argentina banning commercial importation of alien bumblebees based on expert opinion. The large garden bumblebee, Bombus ruderatus, was first introduced in 1982, and the buff‐tailed bumblebee, Bombus terrestris, has been continually introduced since 1997 as part of the burgeoning bumblebee trade. Both species have subsequently invaded southern South America. Today, the consequences of the growth of the bumblebee trade for agricultural pollination ranks among the top 15 emerging environmental issues likely to affect global diversity.
Documented impacts of these invasions include the severe decline and local extinctions of the sole native Patagonian bumblebee, Bombus dahlbomii, pathogen transmission, flower damage and nectar robbing of native and cultivated plants.
Policy implications. The South American bumblebee invasions portrayed here should alert governments to the unintended consequences of the booming international bee trade. More broadly, this case demonstrates that one country's importation decisions can have policy implications for its neighbours without consultation. Regrettably, coordinated international measures to prevent species invasions are seldom considered in South America or elsewhere, despite existing legal frameworks. The bumblebee case and others provide stark evidence of the pressing need for coordinated specific and general international policies concerning global species trade and their implementation.
The progressive increase in the earth's temperature due to anthropogenic activities is a major concern for humanity. The ensuing heat stress (HS) severely impacts plant growth, endangering ecosystem ...quality and world food security. Plant growth, physiological processes and final amount of edible products are affected by HS to an extent that reflects the physical damages, physiological commotions and biochemical alterations incurred at various growth stages. Therefore, a better understanding of plant behaviour in response to HS has pragmatic implications for devising counter-measures, alleviation strategies, and for acknowledging the differences between HS and the companion drought stress. Conventional breeding, biotechnological and molecular approaches are used to develop HS tolerant genotypes in plant species bred for food/feed uses. Recent achievements in the omics techniques result in a better knowledge of the molecular mechanisms involved in HS. However, shrewd management of crop practices is still helpful to improve plant resilience to HS. Suitable sowing time, seed priming, bacterial seed treatment, nutrient and water management, exogenous application of osmo-protectants, and conservation of soil moisture are important tools to improve plant behaviour under the critical HS scenarios determined by climate change and global warming.
Domestication has resulted in reduced salt tolerance in tomato. To identify the genetic components causing this deficiency, we performed a genome‐wide association study (GWAS) for root Na+/K+ ratio ...in a population consisting of 369 tomato accessions with large natural variations. The most significant variations associated with root Na+/K+ ratio were identified within the gene SlHAK20 encoding a member of the clade IV HAK/KUP/KT transporters. We further found that SlHAK20 transports Na+ and K+ and regulates Na+ and K+ homeostasis under salt stress conditions. A variation in the coding sequence of SlHAK20 was found to be the causative variant associated with Na+/K+ ratio and confer salt tolerance in tomato. Knockout mutations in tomato SlHAK20 and the rice homologous genes resulted in hypersensitivity to salt stress. Together, our study uncovered a previously unknown molecular mechanism of salt tolerance responsible for the deficiency in salt tolerance in cultivated tomato varieties. Our findings provide critical information for molecular breeding to improve salt tolerance in tomato and other crops.
Synopsis
Selection of large fruits in domesticated tomato is linked to a reduction in salt tolerance. This study links domestication‐associated variation in the Na+/K+ transporter‐coding gene SlHAK20 to reduced salt tolerance in cultivated plants.
Root Na+/K+ ratios show a strong positive correlation with fruit weight during tomato domestication.
A variation in SlHAK20 is associated with Na+/K+ ratio modulation in tomato roots under salt stress conditions.
The SlHAK20Hap1 haplotype is more effective than SlHAK20Hap2 in conferring Na+ homeostasis and salt tolerance.
The role of SlHAK20 in regulation of salt tolerance is conserved in rice.
A genome‐wide association study links reduced sodium ion uptake by SlHAK20 transporter to diminished salt tolerance and increased fruit weight in cultivated tomato.
In the most recent scientific reports based on the DNA or RNA-analyses a widespread presence of the filamentous fungi, Mortierella in various environments has been shown. Some strains of this genus ...belong to the plant growth-promoting fungi (PGPF) and are found in the bulk soil, rhizosphere and plants tissues. These microorganisms are also often found in the extremely hostile environments, responsible for improving access to the bioavailable forms of P and Fe in the soils, the synthesis of phytohormones and 1-aminocyclopropane-1-carboxylate (ACC) deaminase, and last but not least the protection of agricultural plants from pathogens. Furthermore, earlier reports classified Mortierella spp. as the saprotrophic microorganisms isolated from the forest litter, and nowadays their status as a very valuable decomposers in the agricultural soils was confirmed. The key features like the ability to survive under very unfavorable environmental conditions and the utilization of carbon sources contained in polymers like cellulose, hemicellulose, chitin make these fungi efficient as the agricultural inoculants. The growing interest in the application of Mortierella spp. is mainly due to the potential use of this genus in the increase of the nutrient uptake efficiency, positive effect in crop protection against adverse conditions, and reduction of chemical fertilizers and pesticides applied. Moreover, activities of Mortierella species selected from the wild or cultivated plants influence the soil microbiota and support the performance of the beneficial microorganisms enhancing significantly crop yield.
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