Effect of integrated biofertilizers with chemical fertilizers on the oil palm growth and soil microbial diversity

Abstract

Prolong use of chemical fertilizers has adversely affected the environment and natural microbial diversity in soil and thereby reduced soil fertility and crop quality. The application of biofertilizers containing a combination of beneficial microorganisms in a formulation with a reduced amount of chemical fertilizer was believed to be more effective compared with the stand-alone application of biofertilizers or chemicals. The objective of this study was to investigate the effect of four different treatments on oil palm growth and soil microbial diversity shift located in Chaah, Achijaya, Johor. The treatments comprised of biofertilizers with zero chemical fertilizer content (BF100), biofertilizer amended with 30% of chemical fertilizer (BF70), 100% chemical fertilizer (CF100), and standard organic fertilizer (SF). The results indicated that the application of BF70 produced the highest oil palm height, meristem diameter, number of fronds , leaf area, wet and dry weight of oil palm leaves. Important macronutrients; nitrogen (N) and potassium (K) were highly significant in the oil palms treated with BF70; which were 2.85% and 4994.20 mg L −1 , respectively. While phosphorus (P) recorded 2147.78 mg L −1 with no significant difference compared to other treatments. Application of BF100 indicated the highest soil microbial biodiversity (H' = 3.4723) while BF70 showed a slightly lower H′ that was 3.2444 for bacteria compared to CF100 (2.2372). Whereas, for fungi, BF70 resulted in the highest H’ (2.6662) compared to BF100 (1.9730) and CF100 (2.3799). Therefore, environmentally friendly biofertilizer integrated with a small rate of chemical fertilizer helps in developing better oil palm growth, balanced and sufficient nutrient availability, and maintaining the survivability of beneficial microorganisms in the soil. • Excessive use of chemical fertilizers in agriculture will lead to more environmental problems. • Researchers have emphasized the usage of environmentally friendly biofertilizers that hold vast potential in meeting plant nutrient requirements. • Integration of biofertilizer with a small rate of chemical fertilizer promised an excellent result compared to the usage of biofertilizer alone and 100% chemical fertilizer.