Response of alfalfa growth to arbuscular mycorrhizal fungi and phosphate-solubilizing bacteria under different phosphorus application levels
Junying Liu, Xuanshuai Liu, Qianbing Zhang, Shengyi Li, Yanliang Sun, Weihua Lu, Chunhui Ma
Abstract
Abstract Alfalfa ( Medicago sativa L.) is an important forage legume in farming and animal husbandry systems. This study assessed the effects of arbuscular mycorrhizal fungi (AMF) and phosphate-solubilizing bacteria (PSB) on alfalfa growth under different phosphorus application levels. In this experiment, a complete randomized block design was used. The following four bacterial applications were used: inoculation of Funneliformis mosseae (Fm), inoculation of Bacillus megaterium (Bm), inoculation of mixed species (Fm × Bm) and noninoculation treatment (CK). Phosphorus (P) treatment was applied at the following four levels: 0 mg kg −1 (P 0 ), 50 mg kg −1 (P 1 ), 100 mg kg −1 (P 2 ) and 150 mg P kg −1 (P 3 ). The results showed that with the increase in phosphorus application, each index increased first and then decreased. The J 2 treatment was significantly greater than the J 0 treatment ( P < 0.05) under the same bacterial treatment. In each cropping period the difference in each index to alfalfa was extremely significant under J, P treatment and J × P interactive treatment ( P < 0.01). The indexes were compared by membership function. The priority order was as follows: J 3 P 2 > J 1 P 2 > J 3 P 1 treatment. Therefore, when phosphorus was applied at 100 mg kg −1 , the mixed inoculation of Fm × Bm was optimal, benefitting mycorrhiza growth and the production performance of alfalfa.