Wheat Yield, Physiology and Phenology Response to AM Fungi Application and Phosphorus Management

Abstract

W heat (Triticum aestivum L.) accounts for the largest source of vegetable protein in human food as well as it fulfills about half of the carbohydrates and one-fifth of the global food calories requirement (FAO, 2020). In Pakistan, it provides nearly 30% to the total food grain basket particularly under cere-Abstract | Calcareous soils, particularly having high calcium and carbonate contents reduce Phosphorus (P) solubility and forming complex P compounds, make it unavailable to plants. Inoculation of arbuscular mycorrhizal (AM) fungi could be helpful in the sustainable management of immobile P in soil. However, their use in releasing P from alternative sources in alkaline calcareous soils have been little investigated. To explore the influence of AM fungi and P management on wheat productivity, two years of field experiments were carried out at Agronomy Research Farm, The University of Agriculture Peshawar during Rabi season 2018-19 and 2019-20. Randomized complete block design was used to test the efficacy of different P sources {1. Single super phosphate (SSP), 2. Rock phosphate (RP), 3. Poultry manure (PM), 4. 50% SSP + 50% PM and 5. 50% RP + 50% PM} applied at the rate of 60 and 90 kg P ha -1 . These treatments explored with and without incorporation of AM fungi. One control treatment was used for reference. The results exhibited that, AM fungi had non-significant effect on initial phenological stages of wheat like days to emergence and tillering and anthesis but considerable variations were recorded for physiological maturity as well as physiology and yield of wheat crop. Different P levels also revealed the similar trend, 90 kg P ha -1 noted better phenology, physiology and yield of wheat, however keeping monetary and sustainability in consideration reduced P level (60 kg ha -1 ) was more convincing when explored under AM fungi application. Regarding P sources, co-application of SSP and PM in 50:50 ratio, performed comparatively better than the rest of the sources under consideration in field trials. Conclusively, the combined application of SSP and PM at the rate of 60 kg ha -1 along with AM fungi incorporation provides an edge over the conventional use of synthetic P fertilizer. Moreover, AM fungi provides improved infrastructure to transfers P to plants for growth promotion under reduced P level, and had more potential to improve wheat yields and P uptake on sustainable basis in P deficient calcareous pH soils.