Biochar Application and Rhizobium Inoculation Increased Intercepted Radiation and Yield of Chickpea in Contrasting Soil Types

Soil amendments such as biochar and biofertilizers may improve chickpea productivity but there is limited information on whether this response could be through an increase in soil pH and nodulation. We aimed to determine whether the previously observed positive effects of biochar and rhizobium inoculation on soil pH and chickpea nodulation would result in similar improvements in the proportion of radiation intercepted by the crop canopy, biomass accumulation, and grain yield of three desi chickpea genotypes. Field experiments were carried out in clay and loamy sand soils in two successive years. Biochar application and rhizobium inoculation increased biomass accumulation, chlorophyll content, the proportion of intercepted radiation, and decreased chlorophyll a/b ratios which suggests that biochar and rhizobium inoculation increased biomass accumulation by increasing antenna size and canopy cover. Although rhizobium inoculation increased grain yield of all genotypes, the increase was greater in the best performing genotype, Acc#6. Biomass was highest at 10 t ha−1 and 20 t ha−1 biochar in the clay and loamy sand soil, respectively, suggesting that the lighter soils require higher biochar rates compared to the heavier soils for optimal biomass accumulation.