Improving phosphorus use efficiency: a complex trait with emerging opportunities

Abstract

SUMMARYPhosphorus (P) is one of the essential nutrients for plants, and is indispensable for plant growth and development. P deficiency severely limits crop yield, and regular fertilizer applications are required to obtain high yields and to prevent soil degradation. To access P from the soil, plants have evolved high-and low-affinity Pi transporters and the ability to induce root architectural changes to forage P. Also, adjustments of numerous cellular processes are triggered by the P starvation response, a tightly regulated process in plants. With the increasing demand for food as a result of a growing population, the demand for P fertilizer is steadily increasing. Given the high costs of fertilizers and in light of the fact that phosphate rock, the source of P fertilizer, is a finite natural resource, there is a need to enhance P fertilizer use efficiency in agricultural systems and to develop plants with enhanced Pi uptake and internal P-use efficiency (PUE). In this review we will provide an overview of continuing relevant research and highlight different approaches towards developing crops with enhanced PUE. In this context, we will summarize our current understanding of root responses to low phosphorus conditions and will emphasize the importance of combining PUE with tolerance of other stresses, such as aluminum toxicity. Of the many genes associated with Pi deficiency, this review will focus on those that hold promise or are already at an advanced stage of testing (OsPSTOL1, AVP1, PHO1 and OsPHT1;6). Finally, an update is provided on the progress made exploring alternative technologies, such as phosphite fertilizer.

Similarities and Differences in the Acquisition of Fe and P by Dicot Plants

“…Nowadays, finding new alternatives to the use of P and Fe fertilizers is urgent in order to minimize their environmental impacts, and to lower costs for farmers due to the high prices of both fertilizer [165]. Fe and P are essential elements for plants and are closely interrelated.…”

Phosphorus Transport in Arabidopsis and Wheat: Emerging Strategies to Improve P Pool in Seeds

“…Phosphorus (P) is an essential macronutrient for plant growth and production [1,2]. P deficiency is a generally widespread stressor occurring in natural and agricultural environments.…”

“…P deficiency is a generally widespread stressor occurring in natural and agricultural environments. Consequently, global agricultural crop production has been severely affected [2,3]. It is estimated that crop yield on 30-40% of the world's total arable land is limited by inorganic phosphate (Pi) bioavailability [4,5].…”

“…Many causes could explain the low availability of Pi to plants, such as the Pi (HPO 4 2− ) interaction with soil cations such as zinc (Zn 2+ ) or iron (Fe 2+ ), which form an insoluble complex [6][7][8]. In addition, and most importantly, global Pi reserves are rapidly decreasing due to an increase in its demand [2,[9][10][11]. Analysis of data collected over 14 years revealed that the usage of global P fertilizer considerably increased at a rate of about 357,000 t/annum (i.e., an annual increase of 2.4%) [12,13].…”

Phosphorus and Iron Deficiencies Influences Rice Shoot Growth in an Oxygen Dependent Manner: Insight from Upland and Lowland Rice

“…P is a component of vital biological molecules including nucleic acids, energy sources, phospholipids, and phytic acid [11], and is also involved in the photosynthetic activity [11]. As a result, the content of P is in the range of 0.43%–0.83% of rice dry matter [12], and P starvation results in plants with stunted growth. Fe, an essential micronutrient for cell functioning, plays a cofactor role in metabolic pathways, especially in the photosynthetic activity [13].…”