Can organic soil ameliorant and foliar organic fertilizer improve maize yield and reduce inorganic fertilizers input in a dryland semiarid?

Abstract

There is still room for improving maize yield and cultivation practices in dryland semiarid areas since the current production is still low and the inorganic fertilizers (IF) input is high. This study aimed to assess possible roles of a commercially available organic soil ameliorant (OSA) and foliar organic fertilizer (FOF) to improve maize yield and to reduce IF input in a dryland semiarid area. One experiment with seven treatments were tested, namely: (A) 100% of IF doses, that consisted of 500 kg of urea and 360 kg of NPK Phonska (15-15-15) per hectare, (B) Treatment A plus OSA and FOF, (C) 70% of IF doses plus OSA and FOF, (D) Treatment A plus OSA, (E) 70% of IF plus OSA, (F) Treatment A pus FOF, and (G) 70% of IF plus FOF. The size of each treatment plot was 10.1 m2 and there were 90 plants in each plot. All the treatments were replicated three times and were arranged in a randomized block design. The results showed that the IF treatment (A) produced 11.0 kg per plot, equal to 10.9 ton/ha. Adding OSA or FOF on top of IF (D and F), produced only 3% higher than the IF alone. However, when OSA and FOF were applied together with IF (B), the yield was 6% higher than the IF alone. The 30% reduction of inorganic fertilizer could not be replaced by both OSA and FOF (E and G) in producing yield. OSA improved soil nutrients, such as available phosphorous, potassium and C-organic but not the total nitrogen.