Received: 30-11-2022 / Accepted: 04-08-2023
The study was conducted to determine the efficacy of biofertilizers carrying strains of nitrogen-fixing and phosphorous-solubilizing purple non-sulfur bacteria (Rhodopseudomonas palustris) TLS06, VNW02, VNW64 and VNS89 (CPVS-NP) on black beans growth and yield. The experiment followed a completely randomized block design with 5 treatments and 4 replications, each of which corresponded to a pot. The treatments were (i) 100% N, P;(ii) CPVS-NP combined with 75% N, P;(iii) CPVS-NP combined with 50% N, P;(iv) CPVS-NP only;(v) not supplying CPVS-NP and no chemical fertilizers. The results showed that supplying CPVS-NP combined with75% N, P increased PNSB density and obtained the plant height, leaves number per plant, leaf length, leaf width and the branches per plant equivalent to or higher than those in the treatment fertilized with100% N, P. Supplying CPVS-NP plus 75% N, P enhanced yield by 22.0% compared to that in the treatment fertilized with 100% N, P.