The root endophytes Trametes versicolor and Piriformospora indica increase grain yield and P content in wheat

BACKGROUND AND AIMS: Soil phosphorus (P) deficiency occurs in many developing and transition countries. One method of resolving soil P deficiency is a strong application of mineral and organic fertilizers in order to saturate the P binding capacity of soil. Another promising method is the implementation of crop-endophyte symbioses in combination with the application of smaller amount of P fertilizer. This study comparatively examined the effect of the fungal endophytes Trametes versicolor and Piriformospora indica in P-deprived and P-rich conditions on P uptake and yield in wheat (Triticum aestivum L., cv. Bobwhite). METHODS: Three-day-old wheat seedlings were dip-inoculated with mycelia of (a) T. versicolor WC16GW axenically isolated from Galium album, a dicotyledonous plant obtained from grassland in Linden near Giessen, Germany, and (b) axenic cultures of P. indica DSM 11827 freshly re-isolated from surface-sterilized barley roots. Seedlings were subsequently grown in 6 l Mitscherlich pots (eight seedlings per pot) in soil containing mono-calcium phosphate [CP, Ca (H₂PO₄)₂] with 100 mg P kg⁻¹ soil and control (CO) with 6.3 mg CAL-P kg⁻¹ soil P in an open-air pot experiment station for three months. RESULTS: Colonization of wheat roots by T. versicolor and P. indica increased plant biomass, yield and P content. T. versicolor-colonized plants exhibited a significant increase in grain yield of 37% (CO treatment) and 8.5% (CP treatment), as well as straw yield of 27% (CO treatment) as compared to non-colonized plants. P. indica-colonized plants showed a significant increase in grain yield of 10% under high P (CP treatment) and straw yield of 22% (CO treatment). Moreover, P. indica improved grain P content by 30% (CO treatment), 16% (CP treatment) and straw P content by 33% (CO treatment), while T. versicolor increased grain P content by 16% (CP treatment) and straw by 35% (CP treatment). CONCLUSIONS: Both T. versicolor and P. indica improved wheat P uptake in both P-deprived and P-rich conditions. T. versicolor supported a high grain yield under the CO and CP treatments, suggesting this fungus has a promising potential for P management in cereal crops.