Wheat / Faba Bean Intercropping Improves Physiological and Structural Resistance of Faba Bean to Fusaric Acid Stress.

Abstract BackgroundThe succession cropping obstacle of faba bean are main common and increasingly serious. Soil-borne fusarium wilt is one of the most serious diseases threatening faba bean production. Fusarium oxysporum f. sp. fabae (FOF) is the causal agent of fusarium wilt. Fusaric acid (FA), produced by FOF, plays an important role in the occurrence of disease, and intercropping is an effective measure for control of disease and for improving host resistance in plants. Intercropping is a traditional farming measure that uses inter-species interaction to control pests and diseases and increase food production. The objective of the current study was to investigate the physiological and biochemical responses, and mechanisms of tissue structure resistance of intercropped faba beans following exposure to FA.ResultsResults demonstrated that increasing concentrations of FA had greater effects on faba beans and intercropping significantly reduced red ink absorption of faba beans (33.2%), increased water content (3.1%) and increased activity of the root antioxidant enzymes peroxidase (POD) and catalase (CAT) (26.3% and 2.2.%, respectively). Furthermore, increased lignin content and callose deposition in plant vessels were observed (12.5% and 42.7%) when subject to the high concentration of FA (200mg.L-1) stress, respectively. Intercropping resulted in more intact root cell morphology, increased occurrence of intracellular vacuoles, cell wall thickness and the number of mitochondria and rough endoplasmic reticulum.ConclusionsThis study contributes to us to understand the wheat / faba bean intercropping system at the physiological, tissue and subcellular levels to effectively alleviate the wilting effect of Fusarium toxin on faba bean.