Agriculture is faced with many challenges including loss of biodiversity, chemical contamination of soils, and plant pests and diseases, all of which can directly compromise plant productivity and health. In addition, inadequate agricultural practices which characterize conventional farming play a contributory role in the disruption of the plant-microbe and soil-plant interactions. This review discusses the role of organic amendments in the restoration of soil health and plant disease management. While the use of organic amendments in agriculture is not new, there is a lack of knowledge regarding its safe and proper deployment. Hence, a biorational approach of organic amendment use to achieve sustainable agricultural practices entails the deployment of botanicals, microbial pesticides, and organic minerals as organic amendments for attaining plant fitness and disease suppression. Here, the focus is on the rhizosphere microbial communities. The role of organic amendments in stimulating beneficial microbe quorum formation related to the host-plant-pathogen interactions, and its role in facilitating induced systemic resistance and systemic-acquired resistance against diseases was evaluated. Organic amendments serve as soil conditioners, and their mechanism of action needs to be further elaborated to ensure food safety.

Field experiments were conducted to investigate the variations in sixteen maize genotypes in relation to drought tolerance. The experimental set up was subjected to drought stress after five weeks of planting for three weeks before data on morphological and yield characters of maize genotypes were obtained for three cropping years. Plant height and grain yield of Bodija yellow maize were the highest overall. There was a significant difference among genotypes for drought stress resistance and Bodija yellow maize showed the most tolerance, while TZBR Comp 1 -C1 S2 510 genotype was the least. First principal component axis (Prin 1) had the highest contribution to the variation of the morphological, yield and drought tolerance traits. Prin 1 was highly related to the morphological and yield characters more than to the drought resistance. Plant height was negatively and strongly correlated (p<0.01) with stem height, number of leaves, stem girth, leaf length, leaf width and week after planting, but negatively correlated with the drought resistance. Therefore, Bodija yellow maize should be considered as parent material in breeding for the development of drought tolerant traits in maize.

Plants are exposed to different environmental stresses (biotic or abiotic) in their habitats, these stresses often result in several diseases and decline in crop production which are major concerns to crop producers and scientists. Habitat‐imposed biotic stress is one of the most common problems of crop production. The use of chemical‐based pesticides has been widely reported to control plant diseases but the residual effects of excessive application of pesticides necessitates the use of biological control agents known to play important safety roles in plant disease management. Symbiotic associations between diverse microorganisms and plant roots have also been proven to have enormous impacts on their respective growths and survival; induced systemic resistance (ISR) is part of the mechanism through which plant‐growth‐promoting bacteria and fungi stimulate plant growth and resistance to pathogens. Many of these microorganisms act as stimulants which can be exploited for boosting nutrient uptake, pest control and to protect crops from environmental stresses for better growth. This review focuses on the plant diseases, microbial stimulants and their mechanisms as nutrient enhancers in crop production as well as their potentials in biological control of plant diseases through ISR.

Plant health is essential for food security, and constitutes a major predictor to safe and sustainable food systems. Over 40% of the global crops' productions are lost to pests, insects, diseases, and weeds, while the routinely used chemical-based pesticides to manage the menace also have detrimental effects on the microbial communities and ecosystem functioning. The rhizosphere serves as the microbial seed bank where microorganisms transform organic and inorganic substances in the rhizosphere into accessible plant nutrients as plants harbor diverse microorganisms such as fungi, bacteria, nematodes, viruses, and protists among others. Although, the pathogenic microbes initiate diseases by infiltrating the protective microbial barrier and plants' natural defense systems in the rhizosphere. Whereas, the process is often circumvented by the beneficial microorganisms which antagonize the pathogens to instill disease resistance. The management of plant health through approaches focused on disease prevention is instrumental to attaining sustainable food security, and safety. Therefore, an in-depth understanding of the evolving and succession of root microbiomes in response to crop development as discussed in this review opens up new-fangled possibilities for reaping the profit of beneficial root–microbiomes' interactions toward attaining sustainable plant health.

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