Effects of irrigation quantity and biochar on soil physical properties, growth characteristics, yield and quality of greenhouse tomato
Abstract Considering the challenges faced by current agricultural industry, such as less cultivable land, lack of soil nutrient value, limited water resources, low yield and fruit quality (Appearance and nutritional values) Biochar application was found effective way to improve soil physical properties, consequently, yield and quality of tomatoes. Biochar at three levels: B0 (0 ton/ha) B1 (25 tons/ha) and B2 (50 tons/ha) with three levels of drip irrigation quantity: full irrigation T1 (1.4 pan evaporation Ep) moderate water deficit T2 (1.2 Ep) and severe water deficit T3 (1.0 Ep) were applied in greenhouse. Thus, nine treatments, i.e. T1B0, T1B1, T1B2, T2B0, T2B1, T2B2, T3B0, T3B1 and T3B2 were set. The effects of applied different levels of irrigation quantity and biochar on soil physical properties, crop growth, yield and fruit quality were observed. Increasing level of applied irrigation quantity and biochar could improve the physical properties of soil effectively: decreased, increased and varied the soil bulk density, porosity and 3 phase composition of soil respectively. It is found that increasing levels of applied irrigation quantity at B2 had good effects on bulk density, porosity and 3 phase proportion of soil, and best composition of 3 phase (solid and pores: liquid gas were 33.68 and 66.32 respectively) at T2B2 was found. The growth rate, considering growth parameters: plant height and stem diameter, was increased by applying adequate level of irrigation quantity and biochar. The yield was found maximum at T1B2, which was increased by 30.92 as compared to T1B0. For T3 level, biochar application increased tomato yield, as compared to B0 by 83.69 and 176.60 at B1 and B2 respectively. It is concluded that application of biochar under full and severe deficit irrigation level increased tomato yield effectively, but tomato growth could inhibit under moderate water deficit irrigation, caused a slight yield reduction.