Growth, nutrient uptake, and yieldpromotion of broccoli by plantgrowth promoting rhizobacteriawith manure

Abstract

This study was conducted to investigate the effects of root inoculations with Bacillus cereus (N2-fixing), Brevibacillus reuszeri (P-solubilizing), and Rhizobium rubi(both N2-fixing and P-solubilizing) on plant growth, nutrient uptake, and yield of broccoliin comparison with manure (control) and mineral fertilizer application under fieldconditions in 2009 and 2010. Bacterial inoculations with manure compared with controlsignificantly increased yield, plant weight, head diameter, chlorophyll content, nitrogen(N), potassium (K), calcium (Ca), sulfur (S), phosphorus (P), magnesium (Mg), iron (Fe),manganese (Mn), zinc (Zn), and copper (Cu) content of broccoli. The lowest yield perplant, plant weight, steam diameter, and chlorophyll content were recorded in thecontrol, but the manure with Bacillus cereus (BC), Rhizobium rubi (RR), and Brevibacillusreuszeri (BR) inoculations increased yield 17.0%, 20.2%, and 24.3% andchlorophyll content by 14.7%, 14.0%, and 13.7% over control, respectively. Bacterialinoculations with manure significantly increased uptake of macronutrients and micronutrientsby broccoli. In conclusion, seedling inoculation with BR and especially RR maypartially substitute costly synthetic fertilizers in broccoli.