Effect of Bacillus subtilis and Bacillus amyloliquefaciens culture on the growth and yield of off-season potato (Solanum tuberosum L.)

Abstract

A study was carried out in order to investigate the effect of microbial fertilizer application on off-season potato (Solanum tuberosum L. cv. Universia) under field conditions in early spring and late autumn in 2016. The experiment included Control (C, no application), Standard Fertilizer Application (SFA), Microbial Fertilizer Application (MFA) and SFA+MFA treatments. An equal mixture of three strains of Bacillus subtilis VKPM B-10641(DSM 24613), Bacillus amyloliquefaciens VKPM B-10642 (DSM 24614) and Bacillus amyloliquefaciens В-10643 (DSM 24615) was applied at 1x109 cfu/ml to tubers before planting and to plants at flowering stage in MFA and SFA+MFA plots. Treatments affected the plant growth parameters. SFA plots produced the highest tuber yields in both seasons. MFA plots had earlier emergence time (40 days), higher number of stems per plant (3), higher number of leaves per plant (37.2), thicker stem diameter (10.15 mm), higher above ground biomass yields (5.42 t/ha), higher single tuber weight (104.21 g) and higher tuber yields (22.06 t/ha) compared with control plots (42 days, 2.2, 31.2, 9.15 mm, 4.40 t/ha, 90.88 g and 20.14 t/ha respectively). Tuber yield in MFA plots (26.56 t/ha) was equal to SFA plots (26.81 t/ha) in warmer autumn planting. Combination of SFA and MFA produced lower tuber yields (21.72 t/ha) than SFA treatment (26.81 t/ha). In conclusion, Bacillus subtilis and Bacillus amyloliquefaciens gave comparable tuber yields to chemical fertilizer application in warmer autumn plantings, but lower tuber yields in colder spring conditions warranting further experiments with cold tolerant psychrophilic bacterial strains for off-season potato production.