Effects of corn cob biochar on physiological responses and yield of chili peppers

Abstract

Biochar is a porous and carbon-rich material that is used in soil reclamation to improve the quality of acidic tropical agricultural soils. It has become an important tool for enhancing agricultural productivity. This study aims to investigate how corn cob biochar (CCB) affected the development, fruit yield, and photosynthetic efficiency of chili peppers (Capsicum annuum L.) grown for 91 days in acidic soils with a low pH of 4.3. Two treatments, CCB and non-CCB were established in a randomized complete block design. There were six replications in each treatment. The acidic soil was treated with 37.5 t/ha of CCB, and chili peppers were grown in the experimental plots containing the acid soil with CCB applications. The application of CCB considerably (p < 0.05) enhanced the performance index (Pi), single photon avalanche diode (SPAD) value, and chlorophyll fluorescence (Fv/Fm); however, it did not affect the total quantity of chlorophyll and carotenoids. Moreover, CCB also enhances plant growth and fruit production by increasing the sugar content of the leaves (p < 0.05) after 63–84 days of amendment. After treatment, the soil pH increased from 4.3 to 5.8. These findings confirm that CCB can be used for soil reclamation in acidic soil to efficiently increase soil pH and improve chili pepper productivity.