ENRICHMENT OF CASING SOIL WITH FE AND SOY-FLOUR UNDER Pseudomonas INOCULATION ON YIELD AND QUALITY OF BUTTON MUSHROOM

Effects of casing soil enrichment with soybean flour (SF) and iron (Fe) were explored on yield and quality of edible mushrooms inoculated with plant growth-promoting bacteria in a factorial experiment with four replications. Fe from Fe chelate source was applied at two levels of 0 (Fe 0 ) and 500 mg L -1 (Fe 500 ), SF at three levels of 0% (SF 0 ), 1.5% (SF 1.5 ), and 3% (SF 3 ) of compost dry weight, and bacteria inoculation at two levels (non-inoculation and inoculation of mycelia with  P. putida ). The maximum fresh yield (20.3 kg m -2 ), mushroom number (1041), biological efficiency (95.0%), vitamin C (3.74 mg 100 g -1 FW), and yield of protein (6.48 kg m -2 ) were obtained from SF 1.5 +  P. putida . But, the maximum tryptophan (1.37 mg g -1 DW), methionine (2.29 mg g -1 DW), and antioxidant capacity (4.25 mg mL -1 ) were related to SF 3 inoculated with  P. putida . Furthermore, the maximum carbohydrate (5.64%) was related to Fe 500 + SF 3 . Based on the results, casing soil enrichment with Fe did not have a significant influence on quantitative and qualitative traits of mushrooms, but SF application at the rate of 1.5%, especially when accompanied by  P. putida , played a more essential role. Thus, it is recommended to use 1.5% SF along with  P. putida  to enhance the yield and qualitative traits of edible mushrooms.