The fine‐tuning of mycorrhizal pathway in sorghum depends on both nitrogen−phosphorus availability and the identity of the fungal partner

• Published in: Plant, cell and environment Vol. 45; no. 11; pp. 3354 - 3366
• Main Authors: Raphael, Boussageon, Nicolás, Marro, Martina, Janoušková, Daphnée, Brulé, Daniel, Wipf, Pierre‐Emmanuel, Courty
• Format: Journal Article
• Language: English
• Published: United States Wiley Subscription Services, Inc 01.11.2022; Wiley
• Subjects: Ammonium; Ammonium Compounds - metabolism; arbuscular mycorrhizal symbiosis; Arbuscular mycorrhizas; Edible Grain - metabolism; environment; Food sources; fungi; Gene expression; Genotypes; Glomus mosseae; Life Sciences; Mycorrhizae - metabolism; mycorrhizal and direct pathways; mycorrhizal fungal species; Nitrogen; Nitrogen - metabolism; nutrient translocation; Nutritional status; Phosphate Transport Proteins - genetics; Phosphate Transport Proteins - metabolism; phosphates; Phosphorus; Phosphorus - metabolism; phosphorus and nitrogen supply; Physiological responses; Physiology; plant nutrition; Plant Roots - metabolism; Rhizophagus irregularis; Soil; Sorghum; Sorghum - metabolism; Symbiosis; transcription (genetics); vesicular arbuscular mycorrhizae; plant nutrition; mycorrhizal and direct pathways; phosphorus and nitrogen supply; arbuscular mycorrhizal symbiosis; nutrient translocation; mycorrhizal fungal species; gene expression
• ISSN: 0140-7791; 1365-3040; 1365-3040
• DOI: 10.1111/pce.14426

Sorghum is an important worldwide source of food, feed and fibres. Like most plants, it forms mutualistic symbioses with arbuscular mycorrhizal fungi (AMF), but the nutritional basis of mycorrhiza‐responsiveness is largely unknown. Here, we investigated the transcriptional and physiological responses of sorghum to two different AMF species, Rhizophagus irregularis and Funneliformis mosseae, under 16 different conditions of nitrogen (N) and phosphorus (P) supply. Our experiment reveals fine‐scale differences between two AMF species in the nutritional interactions with sorghum plants. Physiological and gene expression patterns (ammonium transporters: AMT; phosphate transporters: PHT) indicate the existence of generalist or specialist mycorrhizal pathway. While R. irregularis switched on the mycorrhizal pathway independently of the plant nutritional status, F. mosseae influenced the mycorrhizal pathway depending on the N‐to‐P plant ratio and soil supply. The differences between both AMF species suggest some AMT and PHT as ideal candidates to develop markers for improving efficiency of nutrient acquisition in sorghum under P and N limitation, and for the selection of plant genotypes.