Paddy Land Pollutants and Their Role in Climate Change

High salt concentration in soil is a major abiotic stress, which adversely influences the growth, overall development, and productivity of crops. More than 20% of the land of the world used for crop production is adversely affected by high salt concentration. The problem of salt stress becomes a major concern when previously fertile, productive agricultural lands are salinized more profoundly as a result of anthropogenic activities along with natural causes. Therefore, this review is focused on various aspects of salt-affected soils (SAS), their effects on plants, and different approaches for reclamation of SAS to enhance the potentiality for crop production. Salt-affected soils are categorized into saline, saline-sodic, and sodic soils based on the amount of total soluble salts as expressed by electrical conductivity (EC), sodium adsorption ratio (SAR), exchangeable sodium percentage (ESP), and soil pH. The inhibition of plant growth in saline soils is mainly induced by osmotic stress; reduced uptake of essential macro-and micronutrients, including nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu); and specific toxicities of sodium (Na) and chloride (Cl). Sodic soils adversely affect the plant through high soil pH and poor physical condition resulting from an excessive amount of exchangeable Na. Different plants respond to salt stress in different extents. Saltaffected soils must be reclaimed to restore their productivity for increasing food production. The approaches for the management of SAS include leaching, incorporation of different organic and inorganic amendments, mulching, and development of salt-tolerant crops. The suitability of approaches depends on several considerations such as cost of reclamation, the time required, the extent of the salt stress, soil properties, availability of technology, and other environmental factors. Among different strategies, the incorporation of organic amendments is beneficial, costeffective, environment friendly, and sustainable for amelioration of salt stress and enhancement of crop production due to the extensive roles of organic amendments in improving the soil's physical (structural stability, porosity, and permeability), chemical [pH, EC, ESP, organic matter, cation exchange capacity (CEC), and Na leaching], and biological and/or biochemical (microbial abundance, microbial activity, biomass carbon, and enzymatic activities) properties.

Section: Reclamation With Organic Amendmentsmentioning

confidence: 99%

Salt Stress in Plants and Amelioration Strategies: A Critical Review

Roy¹,

Chowdhury²

2021

“…Moreover, breeding for resource use efficiency, for instance, nitrogen use efficiency (NUE) should be integrated in future drought tolerance breeding programs. Previously, researchers have revealed that improving NUE in crops such as paddy rice and cotton will be critical in greenhouse gas emission management [184][185][186][187][188]. Additionally, application of biochar, either singly [189] or in combination with P [190] has been shown to alleviate heat-induced oxidative stress damage on the cellular physiological processes in rice plants.…”

Section: Future Outlookmentioning

confidence: 99%

Adapting Cereal Grain Crops to Drought Stress: 2020 and Beyond

Zenda¹,

Liu²,

Duan³

2021

Among other environmental instabilities, drought stress is the primary limitation to cereal crops growth, development and productivity. In the context of continuing global climate change, breeding of drought resistant crop cultivars is the most economical, effective and sustainable strategy for adapting the crop production system and ensuring food security for the growing human population. Additionally, there is need for improving management practices. Whereas conventional breeding has sustained crop productivity gains in the past century, modern technological advancements have revolutionized our identification of important drought tolerance genes and underlying mechanisms, and accelerated new cultivar development. Large-scale high throughput sequencing, phenotyping, 'omics' and systems biology, as well as marker assisted and quantitative trait loci mapping based breeding approaches have offered significant insights into crop drought stress tolerance and provided some new tools for crop improvement. Despite this significant progress in elucidating the mechanisms underlying drought tolerance, considerable challenges remain and our understanding of the crop drought tolerance mechanisms is still abstract. In this chapter, therefore, we highlight current progress in the identification of drought tolerance genes and underlying mechanisms, as well as their practical applications. We then offer a holistic approach for cereal crops adaptation to future climate change exacerbated drought stress.

“…Abiotic stresses are major environmental conditions that reduce plant growth, productivity, and quality. Plants have evolved mechanisms to perceive these environmental challenges, transmit the stress signals within cells as well as between cells and tissues, and make appropriate adjustments in their growth and development for survive and reproduce [26][27][28][29]. The morphological and physiological changes of perennial ryegrass under abiotic stress will be discussed in this chapter.…”

Section: Abiotic Stressesmentioning

confidence: 99%

Plant Growth and Morphophysiological Modifications in Perennial Ryegrass under Environmental Stress

Xie¹,

Datta²,

Qin³

2021

Perennial ryegrass (Lolium perenne L.) is a popular and important cool-season turfgrass used in parks, landscapes, sports fields, and golf courses, and it has significant ecological, environmental, and economic values. It is also widely used as forage and pasture grass for animals around the world. However, the growth of perennial ryegrass is often affected by various abiotic stresses, which cause declines in turf quality and forage production. Among abiotic stresses, drought, salinity, temperature, and heavy metal are the most detrimental factors for perennial ryegrass growth in different regions, which result in growth inhibition, cell structure damage, and metabolic dysfunction. Many researches have revealed a lot useful information for understanding the mechanism of tolerance to adverse stresses at morphophysiological level. In this chapter, we will give a systematic literature review about morphological and physiological changes of perennial ryegrass in response to main stress factors and provide detail aspects of improving perennial ryegrass resistance based on research progress. Understanding morphophysiological response in perennial ryegrass under stress will contribute to improving further insights on fundamental mechanisms of perennial ryegrass stress tolerance and providing valuable information for breeding resistance cultivars of perennial ryegrass.