Effect of Zn, P and rhizobial inoculant on plant growth and photosynthetic activity of chickpea (Cicer arietinum L.) genotypes planted in soils with different textures under glasshouse conditions

Abstract This study evaluated the effect of phosphate and zinc applied alone and with rhizobia inoculants on plant growth and leaf gas-exchange parameters of chickpea genotypes grown in two contrasting soils. Four chickpea genotypes were subjected to six nutrient management treatments: control, Zn, P, Zn + P, Zn + P + Rₚ (peat-based inoculant), and Zn + P + Rₗ (liquid-based inoculant). Genotype ICCV8101 exhibited high root biomass and root: shoot ratio in both soils. ICCV3110 and ICCV92944 exhibited greater root, shoot, and whole-plant dry weight when grown in silty-clay loam soil, which resulted in a low root: shoot ratio. Applying P alone and in combination with Zn + P, Zn + P + rhizobia inoculant enhanced root and shoot biomass and leaf gas-exchange parameters when compared to sole Zn and control treatments when grown in both soils. However, the response to the fertilizer treatments was genotype- and soil-dependent. For example, in genotype ICCV97024, the highest shoot and whole-plant dry weight, photosynthetic rate, stomatal conductance, and transpiration rate were obtained following application of P alone and Zn + P when established in silty-clay-loam. Similarly, photosynthetic rate, stomatal conductance, and transpiration rate were enhanced by Zn + P + Rp in ICCV3110, while both the combination of Zn + P + Rp and Zn + P + RL improved the parameters in ICCV92944 and ICCV8101 grown in silty-clay loam soils. When established in silty-loam soil, genotypes ICCV3110, ICCV97024, and ICCV92944 exhibited greater root, shoot, and whole-plant dry weight, photosynthetic rate, stomatal conductance, and transpiration rate, and whole-plant dry weight with Zn + P + Rp application. Overall, silty-clay-loam provided more favourable conditions for chickpea growth and photosynthetic functioning.