Wolf Scheible, Ph.D.
Phosphorus is one of the indispensable macronutrients for plant growth, development, and ultimately crop and forage yield. Millions of tons of synthetic phosphorus fertilizers are applied in agriculture to enhance soil phosphorus availability and stimulate crop yields. However, phosphorus fertilizer use poses a twofold sustainability challenge. Intensive application of phosphorus to support high yield agriculture can contribute to eutrophication of aquatic systems, while poor access to affordable fertilizer limits crop yields in developing countries. Moreover, mined rock phosphorus, the primary source of phosphorus fertilizer, is a finite resource subject to large price fluctuations and geopolitical risks. Thus, sustainability of phosphorus is vital for future food security. Achieving phosphorus sustainability will require improvements in phosphorus acquisition and use by plants, thus allowing reductions of phosphorus fertilizer use.
To improve phosphorus acquisition and use by plants, a multitiered research approach is necessary. Research is conducted to expand the understanding about how different model plant species (Arabidopsis thaliana, Medicago truncatula, Brachypodium distachyon, Panicum virgatum) react to changes in phosphorus availability at the molecular level. Cutting-edge, high-throughput (OMICS) technologies are employed in this regard to identify, for example, uncharacterized and even unknown, gene transcripts with strongly phosphorus-status dependent abundance. Interesting molecular components are being investigated using reverse genetic and molecular biology methodologies, and forward genetics is pursued by phenotyping, for example, Medicago truncatula accessions for naturally existing variation with regard to P efficiency, followed by molecular investigation of well and poor performing accessions. Gained knowledge is finally applied to crop/forage plant species using marker-assisted breeding and gene-editing technology in collaboration with colleagues from the Forage Improvement and Agricultural Research Divisions under greenhouse and field conditions.
- Comparative transcriptomics during phosphorus or nitrogen limitation in grasses, legumes and Brassicaceae
- Functional analysis of genes with strongly phosphours-status responsive transcript abundance in Arabidopsis thaliana, Medicago truncatula and Brachipodium distachyon.
- Improving phosphorus acquisition/use efficiency in Medicago spp. and wheat using candidate genes and natural variation
- Identification and functional investigation of small signaling peptides in Medicago truncatula with an emphasis on macronutrient regulation of root and nodule development