Potentially toxic elements (PTE), such as cadmium (Cd), lead (Pb), and arsenic (As), threaten rice (Oryza sativa L.) crop productivity and pose significant risks to human health when they are present in soil. This review summarizes the current understanding of soil and rice contamination with As, Cd, and Pb to provide an in-depth understanding of the dynamics of these contaminants and the mechanisms regulating their flow from soil to plants. It focuses on the following aspects: (1) these metals’ geochemical distribution and speciation in soil–rice systems; (2) factors influencing the transformation, bioavailability, and uptake of these metals in paddy soils; (3) metal uptake, transport, translocation, and accumulation mechanisms in rice grains; and (4) the roles of transporters involved in metal uptake, transport, and accumulation in rice plants. Moreover, this review contributes to a clearer understanding of the environmental risks associated with these toxic metals in soil–rice ecosystems. Furthermore, it highlights the challenges in simultaneously managing the risks of As, Cd, and Pb contamination in rice. The study findings may help inspire innovative methods, biotechnological applications, and sustainable management strategies to mitigate the accumulation of As, Cd, and Pb in rice grains while effectively addressing multi-metal contamination in paddy soils.

Phosphorus (P) is a vital nutrient for global agriculture, playing a pivotal role in crop germination and growth. However, improper usage of phosphorus can lead to detrimental effects on crops and significant environmental pollution. This study investigates the changes in available phosphate (P 2 O 5) concentration in agricultural fields across 17 regions in South Korea from 2013 to 2020. During the study period, the total agricultural land area consistently decreased. Although rice paddy fields accounted for the largest proportion of the total agricultural area, the available P 2 O 5 accumulation was the lowest due to low available P 2 O 5 concentration. In contrast, soils within greenhouses accumulated excessive levels of available P 2 O 5 , significantly exceeding the recommended range. This underscores the importance of improved fertilizer management in greenhouses for the future sustainability of agriculture.

Climate change is causing a variety of environmental issues globally, and the frequency and intensity of droughts in the country are expected to increase. This has heightened the importance of managing agricultural water resources and necessitated the adoption of more efficient farming practices. In this study, we evaluated water inflow, outflow, nutrient concentration, and rice yield under continuous flooding (CF), alternate wetting and drying (AWD) in paddy soils with two different soil textures. AWD proved effective in saving water, as it increased rainfall infiltration and reduced irrigation water input compared to CF. Specifically, in silty clay loam (SiCL) soils, AWD resulted in less water and nutrient outflow than CF. Rice yields increased by 16.4% under AWD compared to CF in SiCL soils, and by 31.9% in sandy loam (SL) soils. These results suggest that water management practices can help mitigate the impact of climate change on irrigation water shortages and increase rice yields across various soil textures compared to conventional farming practices.

Soil plowing depth is very important in improving soil quality and promoting of crop production system. The relationship between soil plowing depth and soil chemical properties and crop yield was analyzed. Soils were sampled from 20 watermelons, 19 muskmelons, and 22 squash farms of plastic film house. The results showed that the average soil plowing depth of watermelon, melon, and squash cultivated in the plastic film house were 22 cm, 21 cm, and 27 cm, respectively. when the soil depth of watermelon and squash was deepened to 31 cm (26-39 cm), the levels of nitrate ion (NO 3-), electrical conductivity (EC), and exchange cations (Ex. cations) decreased by 2-42% compared to 18 cm (14-24 cm). The concentration of NO 3-, EC, and Ex. Potassium (Ex. K) of muskmelon cultivation with soil depth of 28 cm (26-36 cm) tended to decrease by 5-39% compared to 17 cm (14-22 cm). The yield of watermelon, muskmelon, and squash were increased by 6-22% when the soil plowing depth was 39 cm compared to 25 cm. The contribution of plowing depth to yield of 3 crops was highly significant at 13.1-28.2%. Therefore, deep tillage is necessary to improve soil health and increase yield of watermelon, muskmelon, and squash under plastic film house.

Cadmium (Cd) is a potentially toxic element that impairs plant growth and threatens food safety and human health. This study aimed to investigate the effects of sulfur (S) supplementation on Cd uptake and tolerance in rice under hydroponic conditions. Rice seedlings were exposed to Cd stress and treated with S at different concentrations. Physiological traits, oxidative damage markers, thiol compounds, and ionomic profiles in rice plants were assessed. S supplementation reduced Cd-induced growth inhibition, restoring plant biomass. Although Cd accumulation increased with S treatment, it was accompanied by enhanced antioxidant responses, scavenging reactive oxygen species (ROS) and malondialdehyde. S application increased the production of thiol-containing compounds, including γ-glutamylcysteine, glutathione, and phytochelatins, which helped chelate Cd and sequester it in vacuoles, particularly in roots. Additionally, S supplementation altered the essential nutrient composition in rice tissues, particularly the uptake of N, P, and K, while influencing levels of Ca, Mg, and other essential elements. S supplementation enhanced rice tolerance to Cd stress by reestablishing ROS balance, activating thiol-based detoxification pathways, and regulating mineral nutrient balance. Furthermore, sulfur (S) exhibited a dual effect in plants, enhancing cadmium (Cd) uptake while also promoting its detoxification, underscoring its role in improving crop resilience in contaminated soils.