Andrews Danso Ofori

Rice sheath blight (RSB), caused by Rhizoctonia solani, causes 10–50% yield losses globally. Using 16S rRNA sequencing of 100 rice cultivars, we found that resistant varieties harbor significantly more diverse bacterial communities (3230 OTUs; 2064 unique) than susceptible cultivars (599 OTUs; 36 unique). Resistant varieties were enriched in beneficial Burkholderiaceae, Bacillaceae, and Pseudomonadaceae, while Sphingobacteriaceae and Enterobacteriaceae were predominant in the susceptible rice varieties. From the 260 bacterial isolates, Burkholderia vietnamiensis J14EPLEAF2 presented potent antifungal activity (77% inhibition), suppressed lesion development, and abolished sclerotia formation. This strain displayed multiple plant growth-promoting traits, enhanced seed germination, and primed defense responses by upregulating PR5 and PR10. Hypersensitive response assays confirmed B. vietnamiensis as non-pathogenic, unlike B. gladioli and B. cepacia. This study identifies B. vietnamiensis J14EPLEAF2 as a promising, safe biocontrol agent for sustainable rice disease management.

The genus Burkholderia encompasses both plant pathogenic and beneficial species, yet the genomic determinants underlying this lifestyle divergence remain poorly understood. Using 16S rRNA sequencing of 100 rice cultivars, our companion study demonstrated that resistant varieties are enriched in beneficial Burkholderiaceae, leading to the isolation of three phenotypically contrasting strains. Here, we present comparative genomic analyses of non-pathogenic biocontrol strain Burkholderia vietnamiensis J14EpLeaf2 and pathogenic strains Burkholderia gladioli A1EpSeed5 and Burkholderia cepacia J14Eple. Pathogenic strains possess significantly larger genomes (8.36–8.46 Mb) enriched in mobile genetic elements compared to the streamlined 6.95 Mb genome of B. vietnamiensis. CAZyme analysis revealed broader repertoires of glycoside hydrolases and polysaccharide lyases in pathogens, consistent with enhanced plant cell wall degradation. B. gladioli possesses a complete T3SS and expanded T6SS with 301 predicted effectors, while B. cepacia lacks structural T3SS genes but harbors 271 candidate effectors predicted to be secreted via alternative secretion pathways, compared to 180 in B. vietnamiensis. Notably, B. cepacia harbors cystic fibrosis-associated markers (cable pili, ZmpA/ZmpB), raising significant biosafety concerns that preclude its agricultural application. LC-MS validated IAA, ornibactin, and AHL production in B. vietnamiensis, supporting its plant growth-promoting and biocontrol functions. Computational PPI networks predicted distinct interaction landscapes requiring experimental validation. This study provides a genomic framework for distinguishing pathogenic from beneficial Burkholderia and supports B. vietnamiensis as a safe biocontrol agent while cautioning against B. cepacia J14Eple.

Rice (Oryza sativa) is a crucial staple crop for global food security, particularly in Asia. However, rice production faces significant challenges from various diseases that can cause substantial yield losses. This review explores the role of genetic resistance in rice disease management, focusing on the molecular mechanisms underlying plant–pathogen interactions and strategies for developing resistant varieties. The paper discusses qualitative and quantitative resistance, emphasizing the importance of resistance (R) genes, defense-regulator genes, and quantitative trait loci (QTLs) in conferring broad-spectrum disease resistance. Gene-for-gene relationships in rice–pathogen interactions are examined, particularly for Xanthomonas oryzae pv. oryzae and Magnaporthe oryzae. The review also covers recent advancements in breeding techniques, including marker-assisted selection, genetic engineering, and genome editing technologies like CRISPR-Cas. These approaches offer promising avenues for enhancing disease resistance in rice while maintaining yield potential. Understanding and exploiting genetic resistance mechanisms is crucial for developing durable and broad-spectrum disease-resistant rice varieties, essential for ensuring sustainable rice production and global food security in the face of evolving pathogen threats and changing environmental conditions.

The phyllosphere, comprising the aerial portions of plants, is a vibrant ecosystem teeming with diverse microorganisms crucial for plant health and productivity. This review examines the functional roles of phyllosphere microorganisms in rice (Oryza sativa), focusing on their importance in nutrient uptake, disease resistance, and growth promotion. The molecular mechanisms underlying these interactions are explored along with their potential applications in enhancing sustainable rice production. The symbiotic relationships between rice plants and their associated microorganisms are highlighted, offering insights into improved agricultural practices. Furthermore, this review addresses the challenges and future developments in translating laboratory findings into practical applications. By synthesizing current research, this comprehensive analysis serves as a valuable resource for leveraging phyllosphere microbes in rice farming and related fields.

Chilo suppressalis is a notorious pest that attacks rice, feeding throughout the entire growth period of rice and posing a serious threat to rice production worldwide. Due to the boring behavior and overlapping generations of C. suppressalis, the pest is difficult to control. Moreover, no rice variety with high resistance to the striped stem borer (SSB) has been found in the available rice germplasm, which also poses a challenge to controlling the SSB. At present, chemical control is widely used in agricultural production to manage the problem, but its effect is limited and it also pollutes the environment. Therefore, developing genetic resistance is the only way to avoid the use of chemical insecticides. This article primarily focuses on the research status of the induced defense of rice against the SSB from the perspective of immunity, in which plant hormones (such as jasmonic acid and ethylene) and mitogen-activated protein kinases (MAPKs) play an important role in the immune response of rice to the SSB. The article also reviews progress in using transgenic technology to study the relationship between rice and the SSB as well as exploring the resistance genes. Lastly, the article discusses prospects for future research on rice’s resistance to the SSB.

In Ghana, rice remains a critical crop, representing 15% of the country's GDP. However, production has been hindered by limited water access, degraded soil, pests and diseases, and ineffective pesticide use. These issues have impeded industry growth while adversely affecting the environment and impairing socioeconomic development. To combat these challenges, it is necessary to implement sustainable production strategies that emphasize environmental protection, resource management, and socioeconomic progress. This study evaluates sustainable rice production in Ghana, taking into account its consequences on the environment, socioeconomic growth, and food security. It pinpoints gaps and offers advice for stakeholders, policymakers, and scholars to transition to sustainability. The study illuminates the increasing significance of rice in Ghana and its role in food security, illustrating increased output due to widened land rather than higher yields. It underscores the necessity of fulfilling surging demand while implementing environmentally friendly practices. The paper scrutinizes the difficulties encountered by the rice sector, such as restricted water supplies and soil degradation, along with the adverse impacts of pests, diseases and inefficient pesticide utilization. Sustainable methods are imperative for Ghana's agribusiness, environmental protection, and socioeconomic progress. By embracing green techniques, prioritizing resource management, and investing in research, Ghana can surmount production issues. This review provides invaluable insight and suggestions for policymakers, academicians, and stakeholders alike to ensure sustainable rice production for current and future generations.

Streptomyces scabies is a Gram-positive bacterial pathogen that causes common scab disease to several crops, particularly in the potato. It is a soil borne pathogen, a very devastating scab pathogen and difficult to manage in the field. Streptomyces has several species that cause common scab such as S. scabiei, S. acidiscabies, S. europaeiscabiei, S. luridiscabiei, S. niveiscabiei, S. puniciscabiei, S. reticuliscabiei, S. stelliscabiei, S. turgidiscabies, S. ipomoeae. Common scab disease harmfully affects potato economic and market value due to the presence of black spots on the tuber. Owing to its genetic diversity and pathogenicity, the determination of pathogen presence in potato fields is still challenging. In this study, S. scabies genetic diversity was measured by surveying five potato-growing areas of Pakistan during the growing season 2019. A total of 50 Streptomyces isolates, including S. scabies, S. acidiscabies, S. griseoflavus were isolated and identified based on morphologic, biochemical and molecular analysis. Virulent confirmation assays confirmed ten virulent strains of Streptomyces spp. On the potato cultivars Cardinal and Santee. Among the Streptomyces species, S. scabies showed the highest scab index, followed by S. acidiscabies and S. griseoflavus by exhibiting the scab-like lesions on potato tubers. Ten potato cultivars were screened against these virulent isolates of Streptomyces. The Faisalabad white variety showed the highest scab index followed By Cardinal, Tourag, Kuroda, Santee, Lady Rosetta, Asterix, Diamant, Faisalabad red and Sadaf. Moreover, genetic diversity and pathogenicity of Streptomyces spp. on potato tubers were also likely diverse in different geographical regions and also potato cultivars. This study represents a contribution to understanding the local interaction between potatoes and Streptomyces spp. in Pakistan. It will aid in supporting a solution for the management of this pathogen around the world.