Biotechnology of nutrient uptake and assimilation in plants

Abstract

Plants require a complex balance of mineral nutrients to reproduce successfully. Because the availability of many of these nutrients in the soil is compromised by several factors, such as soil pH, cation presence, and microbial activity, crop plants depend directly on nutrients applied as fertilizers to achieve high yields. However, the excessive use of fertilizers is a major environmental concern due to nutrient leaching that causes water eutrophication and promotes toxic algae blooms. This situation generates the urgent need for crop plants with increased nutrient use efficiency and better-designed fertilization schemes. The plant biology revolution triggered by the development of efficient gene transfer systems for plant cells together with the more recent development of next-generation DNA and RNA sequencing and other omics platforms have advanced considerably our understanding on the molecular basis of plant nutrition and how plants respond to nutritional stress. To date, genes encoding sensors, transcription factors, transporters, and metabolic enzymes have been identified as potential candidates to improve nutrient use efficiency. In addition, the study of other genetic resources, such as bacteria and fungi, allows the identification of alternative mechanisms of nutrient assimilation, which are potentially applicable in plants. Although significant progress in this respect has been achieved by conventional breeding, in this review we focus on the biotechnological approaches reported to date aimed at boosting the use of the three most limiting nutrients in the majority of arable lands: nitrogen, phosphorus, and iron.

Challenges of Sustainable and Commercial Aquaponics

“…It is a macronutrient, which is assimilated by plants in its ionic orthophosphate form (H2PO4 ). It is essential for both vegetative and flowering stages of plant growth [78]. In RAS, 30%-65% of the phosphorus added to the system via fish feed is lost in the form of fish solid excretion that is filtered out by either settling tanks or mechanical filters [25,79].…”

Ion Homeostasis Response to Nutrient-Deficiency Stress in Plants

“…Plant growth and development often depend on various biotic and abiotic stressors. In particular, alterations in environmental conditions have a direct impact on the nutrient uptake and assimilation in plants [1]. In this context, a surplus and even more so a deficiency of essential macronutrients in soils represents one of the most common stress types, with nitrogen (N), potassium (K) and phosphorous (P) being the most relevant ones.…”

Engineering crop nutrient efficiency for sustainable agriculture

“…Similarly, the Earth's crust has high contents of organic and inorganic P, but most of the total P (50%–80%) in agricultural soils exists as organic P, which is not directly available to plants unless hydrolyzed by phosphatases to release inorganic P (Pi) (Vincent et al ). The availability of orthophosphates (H 2 PO 4 − and HPO 4 2− ), the only chemical forms that can be acquired and assimilated by plants, is low and Pi is heterogeneously distributed in almost all natural and agricultural ecosystems (López‐Arredondo et al ). Pi availability depends on several factors, including soil pH, the presence of cations, and rapid conversion by soil microorganisms into organic forms (Jenks and Wood ).…”