The development of novel improved varieties adapted to unstable environmental conditions is possible through the genetic diversity of breeding materials. Potato is among the most important food crops worldwide; however, there are still significant hindrances to breeding gains attributed to its autotetraploid and highly heterozygous genome. Bacterial wilt caused by the Ralstonia solanacearum species complex is an important disease affecting potato among many economically important crops worldwide. No cultivated potato genotypes have shown a satisfactory level of resistance to bacterial wilt. Nevertheless, resistance can play a crucial role in effective integrated disease management. To understand the genetic landscape of bacterial wilt resistance in cultivated potato, we evaluated the diversity of 192 accessions from the International Potato Center (CIP) using 9,250 single-nucleotide polymorphisms and their associations with the response to bacterial wilt disease evaluated over two independent trials. Twenty-four accessions showed high resistance throughout both trials. Genetic diversity analysis revealed three major clusters whose subgroups were mostly represented by CIP clones derived from common parents. Genome-wide association analyses identified six major hits: two on chromosome 8 and one on each chromosome 2, 4, 5, and 9. These results facilitate genetic dissection of bacterial wilt resistance and enable marker-assisted breeding in elite genotypes for potato breeding initiatives.

Potato (Solanum tuberosum L.), as the world’s fourth largest food crop, plays a crucial role in ensuring food security through its disease resistance. The RPP13 gene family is known to play a pivotal role in plant disease resistance responses; however, its specific functions in potato remain unclear. In this study, we conducted the first comprehensive identification and analysis of 28 RPP13 gene family members in potato, examining their gene structures, chromosomal locations, expression patterns, and functional characteristics. Gene structure analysis revealed that most members contain the typical CC-NBS-LRR domains, with exon numbers ranging from 1 to 6. Phylogenetic analysis grouped these genes into four evolutionary clades, indicating a high level of conservation. Cis-regulatory element analysis identified that the promoter region of StRPP13-26 is enriched with pathogen-responsive elements such as the WUN-motif and MYC, suggesting its potential role in disease defense. Expression pattern analysis showed that StRPP13-8, StRPP13-10, and StRPP13-23 are highly expressed in various tissues, indicating their involvement in basic physiological functions, whereas StRPP13-6 and StRPP13-25 are mainly induced under specific pathogen infection conditions. Transcriptome and qRT-PCR analyses further revealed functional divergence of the RPP13 gene family in response to potato scab disease. Notably, StRPP13-11 was significantly downregulated in both resistant and susceptible cultivars, suggesting its crucial role in the early stages of pathogen recognition. Subcellular localization experiments showed that the StRPP13-11 protein is localized in the chloroplast. Combined with transcriptome-based functional enrichment analysis, this finding implies that StRPP13-11 may participate in disease defense by regulating photosynthesis-related genes and the dynamic balance of reactive oxygen species within the chloroplast. This study provides new insights into the potential functions of the RPP13 gene family in potato disease resistance mechanisms, offering valuable genetic resources and theoretical support for future disease-resistant breeding programs.

Six potato cultivars developed in Lithuania, ‘VB Venta’, ‘Goda’, ‘VB Liepa’, ‘VB Meda’, ‘VB Rasa’ and ‘VB Aista’, were selected based on the results of trials in the Ukrainian climatic zone from 2020-—2021. Three of the cultivars, ‘VB Goda’, ‘VB Liepa’, and ‘VB Meda’, presented elevated levels of resistance to Synchytrium endobioticum (Schilbersky) Percival and Phytophthora infestans (Mont) de Bary. These cultivars are recommended for use as parental lines for crossing and as sources of disease-resistant potatoes. Simple sequence repeat (SSR) markers are frequently employed in breeding and genetic studies because of their prevalence, repetition, and extensive genome coverage. These results indicate that Lithuanian potato cultivars exhibit significant genetic differences, which also translate into distinct agromorphological characteristics.

The soil-borne pathogen Rhizoctonia solani is one of the most devastating necrotrophic pathogens worldwide, responsible for causing rice sheath blight (RSB). This pathogen has a broad host range, affecting economically important monocots and dicots such as rice, wheat, potato, soybean, sugar beet, and cucumber. Despite extensive screening of rice germplasm, genes that confer full resistance to RSB have rarely been identified, leading to slow progress in breeding resistant varieties. To identify RSB-resistant rice cultivars in Korea, variations in quantitatively inherited resistance have been observed. We conducted a study to visually assess the RSB resistance phenotypes of 250 cultivated varieties under natural disease conditions in the field over several years. Notable candidates included P1401, which showed resistance, while Junam was susceptible. To identify the quantitative trait loci (QTLs) associated with resistance, we developed an F2 mapping population by crossing P1401 and Junam, followed by bulked segregant analysis. These QTLs were mapped to specific locations on seven of the 12 rice chromosomes. This mapping population and the resulting datasets provide valuable resources for advancing genomic research in rice, particularly for marker-assisted breeding strategies for enhancing resistance to R. solani and other important agronomic traits.

‘BRS Gaia’ is a red-skinned potato cultivar with high dry matter and attractive tuber appearance. Its tubers are oval, with shallow eyes, slightly rough skin, yellow flesh and low susceptibility to post-harvest greening. The vine maturity and tuber dormancy are medium. It is moderately susceptible to late and early blight. ‘BRS Gaia’ has an intermediate level of resistance (tolerance) to bacterial wilt, which gives it a significant comparative advantage over traditional cultivars for disease management in areas infested by the bacteria Ralstonia solanacearum. It has low susceptibility to tuber deformation due to high temperature. Although the main destination is for the fresh market, ‘BRS Gaia’ can also be used by restaurants for fresh cut fries and for processing into shoestrings. 'BRS Gaia' was released in 2023 through Embrapa’s potato breeding program, developed by Embrapa Clima Temperado, in Pelotas-RS and Canoinhas-SC, and Embrapa Hortaliças, in Brasilia-DF, Brazil.

Abstract Potato (Solanum tuberosum L.) is a crop of global significance, with significant production in Pakistan, Egypt, etc. it is quite vulnerable to Streptomyces scabies, which causes common scab., leading to substantial yield and economic losses. Conventional control methods, including soil pH adjustment and chemical treatments, are often inconsistent and expensive, necessitating the development of resistant cultivars. This study isolated and purified S. scabies from infected tubers using yeast malt extract agar (YMA). The isolates were confirmed as pathogenic through hypersensitivity tests on Nicotiana tabacum. Ten potato cultivars were screened for resistance under greenhouse conditions using soil inoculated with two virulent S. scabies strains (ENC-2 and AQAB-1). Scab incidence and severity were assessed using a standard scab index. The cultivars showed varying susceptibility levels to S. scabies. Cardinal and Sarpomira exhibited the least susceptibility with scab indices of 10.67 and 12.50, respectively, and disease incidences below 60%. In contrast, Bartina and Desiree were highly susceptible, with scab indices of 24.54 and 24.88 and incidences of 86% and 72.72%. Cardinal and Sarpomira demonstrated as potential least susceptible cultivars against common scab, making them suitable for cultivation in scab-prone regions. Further research should focus on breeding resistant cultivars and exploring integrated management strategies to mitigate common scab in diverse potato-growing environments.

Garlic (<i>Allium sativum</i> L.), a vital global crop, suffers significant losses from soil-borne fungal pathogens such as <i>Fusarium proliferatum</i>, responsible for <i>Fusarium</i> bulb rot, and <i>Stromatinia cepivora</i>, the causal agent of white rot. In May 2023, garlic fields near Makó City, Hungary, showed simultaneous yellowing and wilting symptoms of unknown fungal infestations, which appeared sporadically. The causal pathogens were later confirmed as <i>F. proliferatum</i> and <i>S. cepivora</i> through sampling of symptomatic garlic plants, incubation in humid chambers to stimulate fungal growth, and culturing on Potato Dextrose Agar (PDA) under sterile conditions. This was followed by hyphal tip isolation and purification. Molecular identification was performed using ITS1-2 sequencing, supported with morphological identification based on colony and microscopic features. This research aimed to elucidate pathogen interaction dynamics and assess the resistance of eleven garlic cultivars to both single and simultaneous inoculations by these pathogens, under <i>in vitro</i> and <i>in planta</i> tests. Dual culture assays of <i>F. proliferatum</i> and <i>S. cepivora</i> were studied at two time points: Day 8, marking the cessation of growth along the interacting fronts due to competitive coexistence, and Day 14, when single cultures reached full radial growth. On Day 8, inhibition percentages were 8.47% for <i>F. proliferatum</i> and 6.40% for <i>S. cepivora</i>, reflecting the initial effects of competitive interactions at the point of contact. By Day 14, inhibition rates increased to 25.39% and 28.61%, respectively, highlighting the cumulative effects of sustained competition and the growing difference between single and dual culture growth. Inoculation trials, involving placing fungal disks onto the basal areas of wounded garlic cloves, revealed considerable variability in disease incidence and severity. Cultivars such as ‘Aulxito’, ‘Sabadrome’, ‘Arno’, ‘Garcua’, and ‘Makói Tavaszi’ were highly susceptible to both pathogens, while ‘Flavor’ and ‘Sabagold’ exhibited only mild symptoms when inoculated with <i>F. proliferatum</i> and <i>S. cepivora</i>, respectively. Simultaneous inoculation resulted in more rapid and severe infections, exhibiting disease incidences above 96.00% across all cultivars. Remarkably, the cultivar ‘Elephant’ exhibited complete resistance to both pathogens, even under simultaneous inoculation, highlighting its potential for future garlic resistance breeding programs.