Global distribution, traditional and modern detection, diagnostic, and management approaches of Rhizoctonia solani associated with legume crops

Abstract

Sustainable development relies heavily on a food system that is both safe and secure. Several approaches may lead to sustainability and food safety. An increase in the cultivation of legume crops is one of the approaches for enhancing agricultural viability and ensuring adequate food supply. Legumes may increase daily intake of fiber, folate, and protein as substitutes for meat and dairy. They are also crucial in various intercropping systems worldwide. However, legume production has been hampered by Rhizoctonia solani due to its destructive lifestyle. R. solani causes blights, damping off, and rotting diseases in legume crops. Our knowledge of the global distribution of R. solani associated with legume crops (alfalfa, soybean, chickpea, pea, lentil, common bean, and peanut), detection, diagnosis, and management of legume crops diseases caused by R. solani is limited. Traditional approaches rely on the incubation of R. solani, visual examination of symptoms on host legume crops, and microscopy identification. However, these approaches are time-consuming, require technical expertise, fail to detect a minimal amount of inoculum, and are unreliable. Biochemical and molecular-based approaches have been used with great success recently because of their excellent sensitivity and specificity. Along with conventional PCR, nested PCR, multiplex PCR, real-time PCR, magnetic-capture hybridization PCR, and loop-mediated isothermal amplification have been widely used to detect and diagnose R. solani. In the future, Next-generation sequencing will likely be used to a greater extent to detect R. solani. This review outlines global distribution, survival, infection and disease cycle, traditional, biochemical, molecular, and next-generation sequencing detection and diagnostic approaches, and an overview of the resistant resources and other management strategies to cope with R. solani.

Leguminous Seedborne Pathogens: Seed Health and Sustainable Crop Management

“…The symptoms associated with R. solani ( Table 1 ) infection are various and change based on the host: they include hypocotyl, crown, stem and root rot, blights, wire stem, and damping off [ 72 ]. Being a seedborne pathogen, it can lead to seed rot and decay, pre-emergence damping off, and germination failure [ 73 , 74 ]. Moreover, it has been demonstrated that R. solani can be preserved in different parts of the seeds, including the seed coat, endosperm, and embryos [ 75 ].…”

“…R. solani is usually preserved in the soil or plant debris as sclerotia or, in seeds, in the form of mycelium. Otherwise, the teleomorph form permits the propagation of basidiospores that are carried by the wind and rain, but this form is rarely encountered in fields [ 74 ]. R. solani overwinters in the soil, and the infection starts with mycelium germination through the plant epidermis.…”

“…From then on, Rhizoctonia grows in the root cortex, leading to progressive colonization inside the root and on the root surface. In favorable conditions, the fungus generates dark streaks that can result in root rot and root death [ 74 ]. Evidently, the dramatic symptomatology of the roots also has consequences on the aerial parts of the host, where typical symptoms of R. solani consist of chlorosis, blights, stunting, and leaf wilting [ 74 ].…”

Biological control of damping-off and plant growth promotion in soybean using Trichoderma virens

“…This inoculum is difficult to be controlled using chemicals. Rhizoctonia solani Kuhn infects several crops including soybean, alfalfa, peanut, and mung bean [1][2].…”

“…R. solani may limit legume production because this pathogen causes blight, damping off and rotting disease [1,3]. Infection on soybean may occur at any growth stage and severe damage can be found at seedling growth.…”