The role of phosphate solubilizing fungi from the shallot rhizosphere on increasing the growth and yield of shallot on Andisol

Abstract Plants need the nutrient P to increase growth and yield. P availability is low in Andisol soil and has high retention by 97.8%. Giving the phosphate solubilizing fungi (PSF) is an alternative to increase available P which plants can use to increase growth and yield. This research aims to determine the benefits of providing phosphate-solubilising fungi on the growth and yield of shallots in Andisol. The study used a block randomized design with three replications. The first factor is Andisol soil origin (Karo regency and Tapanuli Utara regency) and the second is isolate of phosphate solubilizing fungi ( Aspergillus niger P13, Aspergillus niger P21, Aspergillus pseudodeflectus BJ21, and Aspergillus niger BJ23). The research results showed that the soil from Karo can increase plant dry weight and root dry weight respectively by 36.38% and 37.66% compared to Tapanuli Utara. The application of Aspergillus pseudodeflectus BJ21 and Aspergillus niger BJ23 fungi was able to increase plant dry weight by 35.10% and 34.25% and root dry weight by 29.38% and 23.46% compared to without PSF application. The soil origin of Karo Regency increased yield by 36.40% from Tapanuli Utara Regency. Giving fungi Aspergillus pseudodeflectus BJ21 and Aspergillus niger BJ23 fungi was able to increase plant dry weight by 35.10% and 34.25% and root dry weight Aspergillus niger P13 was able to increase yield of 65.63% and 63.12% compared to without giving PSF.