Increasing phosphorus inhibits the retention and prevention of cadmium by iron plaque and promotes cadmium accumulation in rice plants

Iron Plaque: A Shield against Soil Contamination and Key to Sustainable Agriculture

Soils play a dominant role in supporting the survival and growth of crops and they are also extremely important for human health and food safety. At present, the contamination of soil by heavy metals remains a globally concerning environmental issue that needs to be resolved. In the environment, iron plaque, naturally occurring on the root surface of wetland plants, is found to be equipped with an excellent ability at blocking the migration of heavy metals from soils to plants, which can be further developed as an environmentally friendly strategy for soil remediation to ensure food security. Because of its large surface-to-volume porous structure, iron plaque exhibits high binding affinity to heavy metals. Moreover, iron plaque can be seen as a reservoir to store nutrients to support the growth of plants. In this review, the formation process of iron plaque, the ecological role that iron plaque plays in the environment and the interaction between iron plaque, plants and microbes, are summarized.

Review: Nutrient-nutrient interactions governing underground plant adaptation strategies in a heterogeneous environment

Plant growth relies on the mineral nutrients present in the rhizosphere. The distribution of nutrients in soils varies depending on their mobility and capacity to bind with soil particles. Consequently, plants often encounter either low or high levels of nutrients in the rhizosphere. Plant roots are the essential organs that sense changes in soil mineral content, leading to the activation of signaling pathways associated with the adjustment of plant architecture and metabolic responses. During differential availability of minerals in the rhizosphere, plants trigger adaptation strategies such as cellular remobilization of minerals, secretion of organic molecules, and the attenuation or enhancement of root growth to balance nutrient uptake. The interdependency, availability, and uptake of minerals, such as phosphorus (P), iron (Fe), zinc (Zn), potassium (K), nitrogen (N) forms, nitrate (NO3-), and ammonium (NH4+), modulate the root architecture and metabolic functioning of plants. Here, we summarized the interactions of major nutrients (N, P, K, Fe, Zn) in shaping root architecture, physiological responses, genetic components involved, and address the current challenges associated with nutrient-nutrient interactions. Furthermore, we discuss the major gaps and opportunities in the field for developing plants with improved nutrient uptake and use efficiency for sustainable agriculture.

Potential functions of engineered nanomaterials in cadmium remediation in soil-plant system: A review

Soil cadmium (Cd) contamination is a global environmental issue facing agriculture. Under certain conditions, the stable Cd that bound to soil particles tend to be remobilized and absorbed into plants, which is seriously toxic to plant growth and threat food safety. Engineering nanomaterials (ENMs) has attracted increasing attentions in the remediation of Cd pollution in soil-plant system due to their excellent properties with nano-scale size. Herein, this article firstly systematically summarized Cd transformation in soil, transport in soil-plant system, and the toxic effects in plants, following which the functions of ENMs in these processes to remediate Cd pollution are comprehensively reviewed, including immobilization of Cd in soil, inhibition in Cd uptake, transport, and accumulation, as well as physiological detoxication to Cd stress. Finally, some issues to be further studied were raised to promote nano-remediation technology in the environment. This review provides a significant reference for the practical application of ENMs in remediation of Cd pollution in soil, and contributes to sustainable development of agriculture.