A three‐year field experiment of faba bean var. minor effects on soil health and production of pepper grown under conventional farming system

Abstract Soil management using natural‐based approaches is becoming essential to minimize the use of synthetic agrochemicals and to ensure sustainability and resiliency of agriculture production. In this study, faba bean ( Vicia faba L.) var. minor was used during three consecutive cropping years as green manure to restore soil fertility and biology and to improve the growth, yield and fruit quality parameters of pepper cv. ‘Baklouti’. Following green manuring with faba bean, significant enhancements in the total nitrogen (N), the available phosphorus (P) and potassium (K) contents, the soil organic carbon (SOC) and the soil organic matter (SOM) levels were recorded. The alkaline phosphatase activity was also increased by 30.04% after faba bean var. minor incorporation into the soil in the third year. The β‐glucosidase and urease activities were increased by 26.8%–34.03% and 47.01%–71.7% in faba bean‐amended soil during the three‐year trials. Green manuring also enriched soil with total cultivable bacteria, Pseudomonas fluorescens , actinobacteria, total fungi and Aspergillus spp. as compared to control soil. Pepper growth and yield parameters were improved by 16.5–33.7% and 27.5% following green manure amendment, respectively. Vitamin C content, total soluble solids (TSS) and titrable acidity of green and red pepper fruits were 39.1%–50.7% and 7.2%–13.4% higher in green manured soil than in control. The calcium, potassium and phosphorus contents were significantly 4.7%–9.6%, 16.4%–18.1% and 41.2%–42.9% higher in red fruits of pepper plants grown on green manured soil. The plant growth and yield parameters together with the fruit biochemical and mineral characteristics were positively linked to NPK soil levels, SOC, SOM and soil microbial population's density and activity. This study clearly demonstrated the efficiency of green manuring using faba bean var. minor residues as potential alternative to agrochemicals for the enhancement of soil health status and the improvement of pepper growth, yield and fruit nutritional quality.