Silicon Effects on the Root System of Diverse Crop Species Using Root Phenotyping Technology

Roots play an essential function in the plant life cycle, as they utilize water and essential nutrients to promote growth and plant productivity. In particular, root morphology characteristics (such as length, diameter, hairs, and lateral growth) and the architecture of the root system (spatial configuration in soil, shape, and structure) are the key elements that ensure growth and a fine-tuned response to stressful conditions. Silicon (Si) is a ubiquitous element in soil, and it can affect a wide range of physiological processes occurring in the rhizosphere of various crop species. Studies have shown that Si significantly and positively enhances root morphological traits, including root length in rice, soybean, barley, sorghum, mustard, alfalfa, ginseng, and wheat. The analysis of these morphological traits using conventional methods is particularly challenging. Currently, image analysis methods based on advanced machine learning technologies allowed researchers to screen numerous samples at the same time considering multiple features, and to investigate root functions after the application of Si. These methods include root scanning, endoscopy, two-dimensional, and three-dimensional imaging, which can measure Si uptake, translocation and root morphological traits. Small variations in root morphology and architecture can reveal different positive impacts of Si on the root system of crops, with or without exposure to stressful environmental conditions. This review comprehensively illustrates the influences of Si on root morphology and root architecture in various crop species. Furthermore, it includes recommendations in regard to advanced methods and strategies to be employed to maintain sustainable plant growth rates and crop production in the currently predicted global climate change scenarios.

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Nutrient Foraging in Plants

Ecology ◽

10.1093/obo/9780199830060-0114 ◽

2013 ◽

Author(s):

Angela Hodge

Keyword(s):

Root System ◽

Plant Species ◽

Spatial Configuration ◽

Root System Architecture ◽

Nutrient Acquisition ◽

Plant Roots ◽

Symbiotic Associations ◽

Gas Phases ◽

Wide Range ◽

Solid Liquid

Soils are physically the most complex of all environments, comprising solid, liquid, and gas phases, and vary considerably in their ability to supply nutrients. Plant roots acquire nutrients from the solution (liquid) phase but the equilibrium among these different phases controls the nutrients available, which also depends on the nutrient in question. Consequently, nutrients in soil are distributed in a non-uniform or heterogeneous manner. This heterogeneity occurs at a range of scales including those relevant to plant roots. Roots therefore have to respond to this heterogeneity or “patchiness” in resource supply in order to acquire nutrients essential for growth and normal metabolic function. This is aided by the modular structure of the root system, which enables flexibility in the spatial configuration of the root system (i.e., root system architecture) and plasticity in physiological and morphological responses. Most early studies focused on measuring the type and size of the observed response to nutrient heterogeneity with little consideration as to what this meant in terms of actual nutrient acquisition. Consequently, there is a vast literature on the various root responses by different plant species conducted under a wide range of environmental conditions but from which comparisons are difficult to make and the importance of the response obscure. More recently, investigative studies have moved toward more emphasis being placed upon the functional importance of the root response in terms of nutrient acquisition and, importantly, the environmental context in which that response is produced. This is an important shift in emphasis, as responses observed under ideal and often controlled conditions may not necessarily relate to those that actually occur in the natural environment. The majority of plant species also have additional means to forage their environment for resources including the formation of mycorrhizal symbiotic associations, while a smaller number of plant species can form symbiotic associations with nitrogen-fixing prokaryotes. Roots can also release substances into the soil that have a specific role to play in nutrient acquisition. Although plants can also forage for resources aboveground, resulting in plasticity in aboveground structures, the majority of plants acquire their nutrients from the soil environment: hence, this is the main focus of the text and resulting bibliography.

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Molecular and Cellular Mechanisms Involved in Host-Specific Resistance to Cyst Nematodes in Crops

Frontiers in Plant Science ◽

10.3389/fpls.2021.641582 ◽

2021 ◽

Vol 12 ◽

Author(s):

Qi Zheng ◽

Vera Putker ◽

Aska Goverse

Keyword(s):

Crop Production ◽

Specific Resistance ◽

Current Knowledge ◽

Defense Responses ◽

Cyst Nematode ◽

Cyst Nematodes ◽

Cellular Mechanisms ◽

Crop Species ◽

Crop Cultivation ◽

Wide Range

Cyst nematodes are able to infect a wide range of crop species and are regarded as a major threat in crop production. In response to invasion of cyst nematodes, plants activate their innate immune system to defend themselves by conferring basal and host-specific defense responses depending on the plant genotype. Basal defense is dependent on the detection of pathogen-associated molecular patterns (PAMPs) by pattern recognition receptors (PRRs), while host-specific defense mainly relies on the activation of canonical and non-canonical resistance (R) genes or quantitative trait loci (QTL). Currently, application of R genes and QTLs in crop species is a major approach to control cyst nematode in crop cultivation. However, emerging virulent cyst nematode field populations are threatening crop production due to host genetic selection by the application of a limited set of resistance genes in current crop cultivars. To counteract this problem, increased knowledge about the mechanisms involved in host-specific resistance mediated by R genes and QTLs to cyst nematodes is indispensable to improve their efficient and sustainable use in field crops. Despite the identification of an increasing number of resistance traits to cyst nematodes in various crops, the underlying genes and defense mechanisms are often unknown. In the last decade, indebt studies on the functioning of a number of cyst nematode R genes and QTLs have revealed novel insights in how plants respond to cyst nematode infection by the activation of host-specific defense responses. This review presents current knowledge of molecular and cellular mechanisms involved in the recognition of cyst nematodes, the activation of defense signaling and resistance response types mediated by R genes or QTLs. Finally, future directions for research are proposed to develop management strategies to better control cyst nematodes in crop cultivation.

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Bee pollination improves crop quality, shelf life and commercial value

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2013.2440 ◽

2014 ◽

Vol 281 (1775) ◽

pp. 20132440 ◽

Cited By ~ 163

Author(s):

Björn K. Klatt ◽

Andrea Holzschuh ◽

Catrin Westphal ◽

Yann Clough ◽

Inga Smit ◽

...

Keyword(s):

Shelf Life ◽

Fruit Quality ◽

Crop Production ◽

The European Union ◽

Bee Pollination ◽

Pollination Services ◽

Crop Species ◽

Crop Quality ◽

Wide Range ◽

Exclusion Experiments

Pollination improves the yield of most crop species and contributes to one-third of global crop production, but comprehensive benefits including crop quality are still unknown. Hence, pollination is underestimated by international policies, which is particularly alarming in times of agricultural intensification and diminishing pollination services. In this study, exclusion experiments with strawberries showed bee pollination to improve fruit quality, quantity and market value compared with wind and self-pollination. Bee-pollinated fruits were heavier, had less malformations and reached higher commercial grades. They had increased redness and reduced sugar–acid–ratios and were firmer, thus improving the commercially important shelf life. Longer shelf life reduced fruit loss by at least 11%. This is accounting for 0.32 billion US$ of the 1.44 billion US$ provided by bee pollination to the total value of 2.90 billion US$ made with strawberry selling in the European Union 2009. The fruit quality and yield effects are driven by the pollination-mediated production of hormonal growth regulators, which occur in several pollination-dependent crops. Thus, our comprehensive findings should be transferable to a wide range of crops and demonstrate bee pollination to be a hitherto underestimated but vital and economically important determinant of fruit quality.

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Trends in Molecular Diagnosis and Diversity Studies for Phytosanitary Regulated Xanthomonas

Microorganisms ◽

10.3390/microorganisms9040862 ◽

2021 ◽

Vol 9 (4) ◽

pp. 862

Author(s):

Vittoria Catara ◽

Jaime Cubero ◽

Joël F. Pothier ◽

Eran Bosis ◽

Claude Bragard ◽

...

Keyword(s):

Molecular Diagnosis ◽

Bacterial Species ◽

Management Strategies ◽

Diagnostic Methods ◽

Plant Diseases ◽

Wild Plants ◽

Future Climate Change ◽

Climate Change Scenarios ◽

Wide Range ◽

Diversity Studies

Bacteria in the genus Xanthomonas infect a wide range of crops and wild plants, with most species responsible for plant diseases that have a global economic and environmental impact on the seed, plant, and food trade. Infections by Xanthomonas spp. cause a wide variety of non-specific symptoms, making their identification difficult. The coexistence of phylogenetically close strains, but drastically different in their phenotype, poses an added challenge to diagnosis. Data on future climate change scenarios predict an increase in the severity of epidemics and a geographical expansion of pathogens, increasing pressure on plant health services. In this context, the effectiveness of integrated disease management strategies strongly depends on the availability of rapid, sensitive, and specific diagnostic methods. The accumulation of genomic information in recent years has facilitated the identification of new DNA markers, a cornerstone for the development of more sensitive and specific methods. Nevertheless, the challenges that the taxonomic complexity of this genus represents in terms of diagnosis together with the fact that within the same bacterial species, groups of strains may interact with distinct host species demonstrate that there is still a long way to go. In this review, we describe and discuss the current molecular-based methods for the diagnosis and detection of regulated Xanthomonas, taxonomic and diversity studies in Xanthomonas and genomic approaches for molecular diagnosis.

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Marine Organisms for the Sustainable Management of Plant Parasitic Nematodes

Plants ◽

10.3390/plants10020369 ◽

2021 ◽

Vol 10 (2) ◽

pp. 369

Author(s):

Pasqua Veronico ◽

Maria Teresa Melillo

Keyword(s):

Crop Production ◽

Control Strategies ◽

Marine Organisms ◽

New Drugs ◽

Effective Control ◽

Parasitic Nematodes ◽

Plant Parasitic Nematodes ◽

Wide Range ◽

Plant Growth Stimulants ◽

Plant Parasitic

Plant parasitic nematodes are annually responsible for the loss of 10%–25% of worldwide crop production, most of which is attributable to root-knot nematodes (RKNs) that infest a wide range of agricultural crops throughout the world. Current nematode control tools are not enough to ensure the effective management of these parasites, mainly due to the severe restrictions imposed on the use of chemical pesticides. Therefore, it is important to discover new potential nematicidal sources that are suitable for the development of additional safe and effective control strategies. In the last few decades, there has been an explosion of information about the use of seaweeds as plant growth stimulants and potential nematicides. Novel bioactive compounds have been isolated from marine cyanobacteria and sponges in an effort to find their application outside marine ecosystems and in the discovery of new drugs. Their potential as antihelmintics could also be exploited to find applicability against plant parasitic nematodes. The present review focuses on the activity of marine organisms on RKNs and their potential application as safe nematicidal agents.

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How Can We Realize Sustainable Development Goals in Rocky Desertified Regions by Enhancing Crop Yield with Reduction of Environmental Risks?

Remote Sensing ◽

10.3390/rs13091614 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1614

Author(s):

Boyi Liang ◽

Timothy A. Quine ◽

Hongyan Liu ◽

Elizabeth L. Cressey ◽

Ian Bateman

Keyword(s):

Sustainable Development ◽

Crop Yield ◽

Crop Production ◽

Sustainable Development Goals ◽

Positive Impact ◽

Total Yield ◽

Maximum Yield ◽

Guizhou Province ◽

Crop Species ◽

Development Goals

To meet the sustainable development goals in rocky desertified regions like Guizhou Province in China, we should maximize the crop yield with minimal environmental costs. In this study, we first calculated the yield gap for 6 main crop species in Guizhou Province and evaluated the quantitative relationships between crop yield and influencing variables utilizing ensembled artificial neural networks. We also tested the influence of adjusting the quantity of local fertilization and irrigation on crop production in Guizhou Province. Results showed that the total yield of the selected crops had, on average, reached over 72.5% of the theoretical maximum yield. Increasing irrigation tended to be more consistently effective at increasing crop yield than additional fertilization. Conversely, appropriate reduction of fertilization may even benefit crop yield in some regions, simultaneously resulting in significantly higher fertilization efficiency with lower residuals in the environment. The total positive impact of continuous intensification of irrigation and fertilization on most crop species was limited. Therefore, local stakeholders are advised to consider other agricultural management measures to improve crop yield in this region.

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Synergy between a shallow root system with a DRO1 homologue and localized P application improves P uptake of lowland rice

Scientific Reports ◽

10.1038/s41598-021-89129-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Aung Zaw Oo ◽

Yasuhiro Tsujimoto ◽

Mana Mukai ◽

Tomohiro Nishigaki ◽

Toshiyuki Takai ◽

...

Keyword(s):

Root System ◽

Crop Production ◽

Soil Surface ◽

P Uptake ◽

Ore Deposits ◽

Root Surface Area ◽

Genetic Traits ◽

P Use Efficiency ◽

Use Efficiency ◽

P Application

AbstractImproved phosphorus (P) use efficiency for crop production is needed, given the depletion of phosphorus ore deposits, and increasing ecological concerns about its excessive use. Root system architecture (RSA) is important in efficiently capturing immobile P in soils, while agronomically, localized P application near the roots is a potential approach to address this issue. However, the interaction between genetic traits of RSA and localized P application has been little understood. Near-isogenic lines (NILs) and their parent of rice (qsor1-NIL, Dro1-NIL, and IR64, with shallow, deep, and intermediate root growth angles (RGA), respectively) were grown in flooded pots after placing P near the roots at transplanting (P-dipping). The experiment identified that the P-dipping created an available P hotspot at the plant base of the soil surface layer where the qsor1-NIL had the greatest root biomass and root surface area despite no genotyipic differences in total values, whereby the qsor1-NIL had significantly greater biomass and P uptake than the other genotypes in the P-dipping. The superior surface root development of qsor1-NIL could have facilitated P uptakes from the P hotspot, implying that P-use efficiency in crop production can be further increased by combining genetic traits of RSA and localized P application.

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Projecting heat-related excess mortality under climate change scenarios in China

Nature Communications ◽

10.1038/s41467-021-21305-1 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Jun Yang ◽

Maigeng Zhou ◽

Zhoupeng Ren ◽

Mengmeng Li ◽

Boguang Wang ◽

...

Keyword(s):

Climate Change ◽

Excess Mortality ◽

Climate Models ◽

Global Climate ◽

Specific Effect ◽

Northern China ◽

The Elderly ◽

Population Ageing ◽

Global Climate Models ◽

Climate Change Scenarios

AbstractRecent studies have reported a variety of health consequences of climate change. However, the vulnerability of individuals and cities to climate change remains to be evaluated. We project the excess cause-, age-, region-, and education-specific mortality attributable to future high temperatures in 161 Chinese districts/counties using 28 global climate models (GCMs) under two representative concentration pathways (RCPs). To assess the influence of population ageing on the projection of future heat-related mortality, we further project the age-specific effect estimates under five shared socioeconomic pathways (SSPs). Heat-related excess mortality is projected to increase from 1.9% (95% eCI: 0.2–3.3%) in the 2010s to 2.4% (0.4–4.1%) in the 2030 s and 5.5% (0.5–9.9%) in the 2090 s under RCP8.5, with corresponding relative changes of 0.5% (0.0–1.2%) and 3.6% (−0.5–7.5%). The projected slopes are steeper in southern, eastern, central and northern China. People with cardiorespiratory diseases, females, the elderly and those with low educational attainment could be more affected. Population ageing amplifies future heat-related excess deaths 2.3- to 5.8-fold under different SSPs, particularly for the northeast region. Our findings can help guide public health responses to ameliorate the risk of climate change.

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Regulation of Seed Dormancy and Germination Mechanisms in a Changing Environment

International Journal of Molecular Sciences ◽

10.3390/ijms22031357 ◽

2021 ◽

Vol 22 (3) ◽

pp. 1357

Author(s):

Ewelina A. Klupczyńska ◽

Tomasz A. Pawłowski

Keyword(s):

Climate Change ◽

Seed Germination ◽

Seed Dormancy ◽

Environmental Conditions ◽

Global Climate ◽

Plant Evolution ◽

Suitable Habitat ◽

Climate Change Scenarios ◽

Adaptation Mechanism ◽

Seed Dormancy And Germination

Environmental conditions are the basis of plant reproduction and are the critical factors controlling seed dormancy and germination. Global climate change is currently affecting environmental conditions and changing the reproduction of plants from seeds. Disturbances in germination will cause disturbances in the diversity of plant communities. Models developed for climate change scenarios show that some species will face a significant decrease in suitable habitat area. Dormancy is an adaptive mechanism that affects the probability of survival of a species. The ability of seeds of many plant species to survive until dormancy recedes and meet the requirements for germination is an adaptive strategy that can act as a buffer against the negative effects of environmental heterogeneity. The influence of temperature and humidity on seed dormancy status underlines the need to understand how changing environmental conditions will affect seed germination patterns. Knowledge of these processes is important for understanding plant evolution and adaptation to changes in the habitat. The network of genes controlling seed dormancy under the influence of environmental conditions is not fully characterized. Integrating research techniques from different disciplines of biology could aid understanding of the mechanisms of the processes controlling seed germination. Transcriptomics, proteomics, epigenetics, and other fields provide researchers with new opportunities to understand the many processes of plant life. This paper focuses on presenting the adaptation mechanism of seed dormancy and germination to the various environments, with emphasis on their prospective roles in adaptation to the changing climate.

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Improving prediction and assessment of global fires using multilayer neural networks

Scientific Reports ◽

10.1038/s41598-021-81233-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jaideep Joshi ◽

Raman Sukumar

Keyword(s):

Global Climate ◽

Grid Cell ◽

Temporal Correlation ◽

Environmental Drivers ◽

Future Climate Change ◽

Burned Area ◽

Climate Change Scenarios ◽

Data Driven Approach ◽

Climate Interactions ◽

Fire Climate Interactions

AbstractFires determine vegetation patterns, impact human societies, and are a part of complex feedbacks into the global climate system. Empirical and process-based models differ in their scale and mechanistic assumptions, giving divergent predictions of fire drivers and extent. Although humans have historically used and managed fires, the current role of anthropogenic drivers of fires remains less quantified. Whereas patterns in fire–climate interactions are consistent across the globe, fire–human–vegetation relationships vary strongly by region. Taking a data-driven approach, we use an artificial neural network to learn region-specific relationships between fire and its socio-environmental drivers across the globe. As a result, our models achieve higher predictability as compared to many state-of-the-art fire models, with global spatial correlation of 0.92, monthly temporal correlation of 0.76, interannual correlation of 0.69, and grid-cell level correlation of 0.60, between predicted and observed burned area. Given the current socio-anthropogenic conditions, Equatorial Asia, southern Africa, and Australia show a strong sensitivity of burned area to temperature whereas northern Africa shows a strong negative sensitivity. Overall, forests and shrublands show a stronger sensitivity of burned area to temperature compared to savannas, potentially weakening their status as carbon sinks under future climate-change scenarios.

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