Genomics-assisted Improvement of Resistance to Insect Pests, Diseases and Nematodes in Tomato: A Critical Appraisal of Discovery, Durability and Deployment

From Diagnosis to Ecological Engineering: Emerging Transformative Approaches to Plant-Parasitic Nematode Management

Plant-parasitic nematodes remain unusually difficult crop pests because their damage is predominantly below ground, their populations are spatially aggregated, and their biological responses are strongly conditioned by host genotype, soil properties, climate and associated microorganisms. Regulatory withdrawal of hazardous fumigants, variable performance of biological products and the limited durability of single resistance genes have intensified the search for approaches that are more selective, anticipatory and ecologically compatible. This critical narrative review evaluates technologies that could materially change how nematode risk is detected, prevented and suppressed. The evidence was organised around precision diagnosis and surveillance; resistant cultivars, effector-informed breeding and genome editing; RNA interference and nanotechnology-enabled delivery; microbiome engineering, biological control and natural metabolites; soil-system redesign through biofumigation and anaerobic soil disinfestation; and newer selective nematicides. The strongest near-term case is not for a stand-alone ‘revolutionary’ product but for an information-led integrated system in which diagnostics determine the target, resistant or edited plants reduce host suitability, ecological practices lower inoculum and improve soil function, and biological or chemical interventions are applied only where their expected benefit exceeds agronomic and environmental costs. Molecular assays and field sensors can improve specificity and timeliness, yet DNA detection does not automatically measure viable infective pressure or economic risk. Gene editing and RNA interference provide unprecedented target precision, but evidence remains concentrated in a small number of crop–nematode combinations and delivery, durability, pleiotropy and regulation remain decisive constraints. Microbial consortia and suppressive-soil approaches are biologically credible but context dependent, whereas newer nematicides offer useful selectivity without removing the need for stewardship. Progress therefore depends on standardised validation, multi-environment field trials, viable-population diagnostics, resistance-management plans, environmental fate studies and delivery models accessible to resource-constrained farming systems. Transformative nematode management is best understood as coordinated redesign of diagnosis, host resistance, soil ecology and intervention timing rather than replacement of one input by another.

Host resistance and susceptibility to tomato leaf curl New Delhi virus: molecular mechanisms, genetic resources, and strategies for durable control

Tomato leaf curl New Delhi virus (ToLCNDV) is a highly adaptable begomovirus with an expansive and ever-increasing host range. Since its first report in the Indian subcontinent, the virus has rapidly spread across Asia, the Mediterranean Basin, North Africa, and other areas, largely due to efficient transmission by the whitefly Bemisia tabaci . The virus causes severe economic losses in tomato and cucurbit crops, with reported yield reductions ranging from 80% to 100% depending on crop stage, host genotype, and epidemic severity. ToLCNDV has a bipartite circular single-stranded DNA genome that encodes proteins involved in replication, movement, pathogenicity, and suppression of host defense responses. Rapid host range expansion, emergence of new strains, and breakdown of resistance have been facilitated by its high mutation rate, frequent recombination, genome reassortment, and interactions with associated DNA satellites. This review summarizes the current knowledge on taxonomy, genome organization, epidemiology, transmission biology, host range, and molecular interactions of ToLCNDV with host plants and vectors. Particular attention is given to natural sources of resistance in tomato and cucurbits, the genetic basis of resistance loci, host susceptibility factors, and viral counter-defense strategies. This review also discusses recent advances in genomics, transcriptomics, proteomics, gene editing, and molecular breeding as promising tools for durable disease management. Although progress has been made in resistance gene discovery and host–virus interaction studies, sustainable management remains challenging due to the rapid evolution of viruses and the adaptability of vectors. The future management of ToLCNDV will be based on a combination of resistant cultivars, clean plant material, correct diagnosis, whitefly control, real-time surveillance, and omics-guided breeding strategies. A systems-level understanding of the host–virus–vector relationship will be essential for developing resilient crop production systems under changing climatic and agricultural conditions.

Marker-assisted selection for tomato spotted wilt virus (TSWV) resistance in Italian tomato genotypes

ABSTRACT The tomato (Solanum lycopersicum L.) is one of the most important vegetables from an economic, social, and nutritional point of view, being widely consumed throughout the world, both fresh and processed. Due to its importance, this crop is a constant focus of genetic improvement programs that seek to develop superior genotypes, such as higher quality, yield, and disease resistance. Thus, the aim of this study was to select experimental indeterminate Italian tomato hybrids with high yield, superior fruit quality, and resistance to TSWV (tomato spotted wilt virus) via molecular markers. The trial was conducted in the municipality of Ijaci, southern Minas Gerais, Brazil. A randomized block design was used, with 16 hybrids (12 experimental and 4 commercial controls), four replications, and five plants per plot. Evaluations were carried out for yield, fruit quality, and resistance to TSWV under natural infection and through molecular markers to identify the Sw5 gene. Six experimental hybrids stood out in terms of high yield, with hybrid TO-014 being superior to the others, presenting better size and higher commercial classification. Most genotypes showed few defects, revealing good qualitative characteristics, with the exception of three hybrids (TO-004, TO-042, and TO-134), which demonstrated greater susceptibility to TSWV. Seven experimental hybrids were considered resistant to TSWV because they carry the Sw-5 gene and did not show symptoms of infection in the field. Six of these hybrids also stood out in terms of yield and fruit quality, demonstrating that resistance to the virus has a direct impact on productive characteristics.

Marker-assisted pyramiding of bacterial leaf blight resistance genes (Xa21, xa13 and xa5) in a short-duration rice cultivar Luit

Advanced host‒pathogen interactions in wheat and Zymoseptoria tritici: invasion strategies and plant defense mechanisms

Ear-feeding resistance offers new insights into host plant resistance to fall armyworm Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) in maize