Effects of sewage sludge vermicompost andudmineral fertilizer application on the abovegroundudbiomass and yield of maize (Zea mays)

摘要

Biological agriculture concept has been recently introduced to solve problems related to the continuous and excessive applicationudof mineral fertilizers for crop production. This concept emphasizes the importance of combined use of organic and mineraludfertilizers. Thus, this research was conducted to investigate the potential of sewage sludge vermicompost to substitute mineraludfertilizer in maize planting. Treatments involved were mixture of vermicompost (VC) and mineral fertilizer (MF) in theudfollowing ratios of VC and MF: 100% VC (T1), 75:25 (T2), 50:50 (T3), 25:75 (T4), and 100% MF (T5) along with T6ud(without fertilizer) as the control. Standard laboratory procedures were used to analyze nutrient and heavy metal concentrationsudin the vermicompost. The fresh yield and total aboveground dry matter biomass of T5 (239.34 gm plant-1 and 75.00 gmudplant-1) were not significantly different with T3 (201.15 gm plant-1 and 73.61 gm plant-1) and T4 (226.49 gm plant-1 andud70.00 gm plant-1), respectively. These results showed that mixing 25% and 50% sewage sludge vermicompost with mineraludfertilizer (T4 and T3) produced similar yield as the conventional rate of mineral fertilizer application (T5). Therefore, theudamount of inorganic fertilizer for maize cultivation could be reduced.