Effect of faba bean (Vicia faba L.)–rhizobia symbiosis on barley's growth, phosphorus uptake and acid phosphatase activity in the intercropping system

Faba bean (Vicia faba L.) is often grown under several nutritional and environmental constraints such as phosphorus (P) deficiency. In the soil, P massively precipitates to form insoluble complexes with the minerals. Cereals-legumes intercropping may promote cereal growth by increasing the amount of available P and N by the legume. The legumes N₂-fixing symbiosis rely on large quantities of phosphorus as a source of energy. The aim of this study was to evaluate the impact of faba bean-rhizobia symbiosis on the growth of barley plants in intercropping system. The study was carried out on two faba bean varieties (Alfia and Karabiga) and barley in a farmer's field in the Haouz region of Marrakesh. At the flowering stage of faba bean plants, growth, nodulation, acid phosphatase (APase) and phytase enzymatic activities and P contents were assessed in all plants parts including their rhizospheric soils. The results showed that intercropping increased barley's growth, P uptake and APase activity in comparison with the monoculture, especially in association with Karabiga variety. This association presented the highest shoot dry weight (SDW) of 2.48 g plant⁻¹ and P content of 7.64 mg g⁻¹ DW. Meanwhile, faba bean presented significant reductions in these traits in intercropping system. The nodulation of both varieties was not significantly varied in response to intercropping. Overall, it seems that faba bean-barley intercropping was beneficial for barley in terms of increasing the P availability and uptake through the stimulation of APase activity in the in the nodules as well as in the rhizosphere.