Bacillus subtilis and Bacillus amyloliquefaciens culture off season potato (Solanum tuberosom L. var Universia) effect on biomass yield

This study was carried out in order to investigate the effect of microbial fertilizer application on growth and yield of off season potato in the late autumn and early spring sowings in field conditions. Four treatments as Control (C, no microbial and commercial fertilizer application), Standart Fertilizer Application, Microbial Fertilizer Application (Bacillus subtilis and Bacillus amyloliquefaciens) and Standart Fertilizer Application+Microbial Fertilizer Application were investigated in 4 replicates on the experimental farm of Akdeniz University, Faculty of Agriculture in Antalya in the growth seasons of early spring and late autumn in 2016. Tubers of potato cv Universia were sprayed in Bacillus subtilis and Bacillus amyloliquefaciens culture at the rate of 1 ml / 10 L water before planting on 9th of January 2016 and 15 th of August 2016. Plants in Microbial Fertilizer Application and Standart Fertilizer Application+Microbial Fertilizer Application plots were further sprayed with the bacterial culture of 1 ml / 100 L water at the beginning of flowering period. Plant growth, development and yield parameters were measured. Bacillus subtilis and Bacillus amyloliquefaciens culture shortened emergence time, enhanced plant growth, produced larger tubers and increased tuber yield compared with control treatment. The advantage of Microbial Fertilizer Application was comparable to Standart Fertilizer Application and standard Standart Fertilizer Application+Microbial Fertilizer Application depending on season. Microbial Fertilizer Application produced 9.2 % more tuber yields in spring and 9.7 % in autumn period over control plots. The advantage of Microbial Fertilizer Application application on total biomass yield was even higher (13% ) in autumn sowing over control. In conclusion, use of microbial fertilisers in place of costly commercial mineral fertilisers, may offer low input potato production in two consequent harvests during cold winter period under mild coastal climates. Microbial Fertilizer Application in off season potato production will leave also enriched soil with microbial flora for the subsequent crop in the rotation.