Native Bradyrhizobium Enhancing the Growth of Two Peruvian Commercial Varieties of Cowpea

Atencia-Rojas W.; Calixto-Garcia A.R.; Guarniz-Polo S.G.; Ocaña-Rodriguez A.W.; Valdez-Nuñez R.A. · Legume Research (2026) · DOI: 10.18805/lrf-876

Resumen

Background: Bradyrhizobium establi shes an eff ective symbiosis with cowpea. This study eval uated the i noculation of seven native strains in two commercial varieties, demonstrating their potential to enhance symbiotic nitrogen fixation (SNF) and contribute to the agronomic utilization of cowpea in degraded soils of the Peruvian arid coast. Methods: We implemented a completely randomized design with ten treatments: seven inoculated with selected Bradyrhizobium strains-four B. yuanmingense (8.1.1, 8.2, 19.3, 20.1), two Bradyrhizobium sp. (1.1, 12.3) and one B. diversitatis 25.1 and three controls-a consortium of effective strains (B. yuanmingense Rc-458-01 and Rc-455-02), a fertilized treatment (40:60:30; N: P: K) and an uninocul ated, unfertilized absol ute control. Reactivated and purifi ed strains were used to prepare inocula. Two cowpea vari eties (Vaina verde INIA-432 and Vai na verde CAR-9) were sown in non-sterile soi l and i noculated with standardi zed cell suspensi ons. We performed two eval uations: At 45 days post-inocul ati on, we assessed symbiotic eff ect iveness through plant height, shoot and root dry weight, nodul e dry weight, number of nodules, shoot nitrogen content and nitrogen accumulati on; at maturity, we evaluated yield and grain quality, including grain nitrogen, phosphorus and potassium content, number of pods per plant, 100-seed weight, grains per pod and grain yield per plant. Result: Inoculation with native B. yuanmingense strains 19.3 and 20.1, as well as Bradyrhizobium sp. 12.3, significantly increased symbiotic and grain-related parameters in both cowpea varieties.

Instituciones: Universidad Nacional de Barranca