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Vigna radiataL., commonly referred to as mungbean or green gram, holds significant importance as a pulse crop in India. However, its productivity is severely impacted by the combined incidence of dry root rot disease and drought stress. Dry root rot, caused by Macrophomina phaseolina, manifests as reduced yield and compromised produce quality. M. phaseolinais a necrotrophic fungus with a broad host range. Screening studies in several crops’ germplasms have shown a skewness towards susceptibility. Further, the fungus has augmented virulence and survivability in soil under low moisture and high heat. Thus, concurrent drought and dry root rot leads to significantly higher yield losses. This review highlights the status of the disease in mungbean and its future implications owing to the changing climate scenario. We also highlight the molecular and genomic studies conducted in mungbean and several other crops to elucidate the mechanisms involved in M. phaseolinaresistance. The review also suggests management practices which can alleviate yield losses in dry root rot affected fields. Understanding the physiological and molecular mechanisms of dry root rot, drought, and their interaction on disease proliferation can help mitigate the challenges associated with dry root rot management and aid future research.

The reactive oxygen species (ROS) including superoxide (O2−), hydrogen peroxide (H2O2), and singlet oxygen (O2−), are the main molecules produced in excessive amounts under stress conditions, leading to cellular damage in plants. These ROS molecules should be effectively removed to impart stress tolerance. Enzymatic scavengers like superoxide dismutase, catalase, and peroxidases plays a significant role in scavenging ROS molecules. However, the functional validation of such genes cloned from hardy crops are very much limited. The present research demonstrates the synergistic effect of co-expressing multiple antioxidant genes encoding copper-zinc superoxide dismutase (Cu/Zn-SOD) and ascorbate peroxidase cloned from hardy crop Pennisetum glaucumto improve single and combined abiotic stress tolerance and also corroborates Chlamydomonasas a valuable model system for functional validation of multi genes, especially for understanding combined stress responses due to its rapid transformation process and molecular similarity to higher plants.

Macrophomina phaseolina(Tassi.) Goid is an emerging pathogen that causes diseases like dry root rot and charcoal rot in more than 100 plant families. Abiotic stresses such as drought, salinity, and heat exacerbate this fungal effect and predispose crops to pathogen attacks. Importantly, these combined stresses lead to significant crop yield losses under field conditions. In this, we review the interaction between the devastating pathogen M. phaseolinaand several abiotic stresses that are more likely to occur in scenarios of climate change. Drought, heat, and salinity are the major stresses that interact with M. phaseolinain the field. We discuss several field studies, unique physiological and molecular responses, and their mechanisms of control in response to combined stress. The net effect of these interactions depends on a multitude of factors; thus, these interactions modify the impact of biotic stresses on plants by altering their susceptibility. The aim of this review is to provide an overview of what is currently known about M. phaseolinaand abiotic stress interactions, as well as several other edaphic factors that interact with plants. We briefly discuss the role of drought, salinity, heat stress, and edaphic factors (such as pH, N, P, K, etc.) that influence pathogen infection in plants. Furthermore, we discuss possible management strategies to combat crop loss due to combined stress. Thus, we suggest the future aspect of combined stress breeding, along with the use of multi-omics techniques and genome editing approaches, to develop cultivars that exhibit stability in a combined stress environment.