Resistant Cultivars Research Articles

Survey and Disease Prevalence of Sorghum Zonate Leaf Spot in the Terai Region of Uttarakhand, India

Aims: The objective of the study was to conduct a disease survey to understand the regional dynamics of sorghum zonate leaf spot disease in the Uttarakhand Terai region. Study Design: The investigation was carried out using a stratified random sampling technique. Place and Duration of Study: GBPUA&T, Pantnagar and Terai Region of Uttarakhand during Kharif 2024. Methodology: The survey was conducted from July to September 2024, covering several stages of sorghum crop development. A stratified random sampling technique was used to select fields, and observations were recorded on plants making five stops in a W-pattern to cover the whole field on foot. The disease incidence and severity were scored and recorded. Results: The survey covered 25 fields and disease incidence & severity were recorded using a standard scale. The study found that the prevalence and severity of zonate leaf spot disease (G. sorghi) varied significantly between locations, with the highest disease incidence in Chikaghat (71.11%) and lowest in Kanthgri (43.56%) from Sitarganj block. Environmental parameters such as temperature, humidity, and rainfall were directly linked to the occurrence and severity of zonate leaf spots. Conclusion: The study concluded that zonate leaf spot disease is a significant problem in the Uttarakhand Terai Region. Developing efficient management techniques to reduce zonate leaf spot negative effects on crop productivity might be facilitated by knowledge of the distribution and contributing elements. To control zonate leaf spot in these areas, more study is required to investigate resistant cultivars and better agronomic methods.

Impact of Carbon Dioxide Levels on Biochemical Parameters Associated with Stem Rot Disease in Groundnut

Background: Sclerotium rolfsii is a widespread soil-borne fungal pathogen recognized for causing disease in a wide variety of agricultural and horticultural crops globally. Despite the economic losses attributed to this pathogen, there are limited reports concerning the biochemical alterations in groundnut in response to increased carbon dioxide levels and pathogen interactions. Methods: A pot culture experiment was carried out at ICRISAT during the rabi season 2022-23 in Open Top Chambers (OTC) to assess the biochemical responses of groundnut to climate change and pathogen interactions. The study was carried out at three different carbon dioxide levels (400 ppm, 550 ppm and 700 ppm) using the susceptible groundnut cultivar TMV 2 and the moderately resistant cultivar ICGV-14082. Result: The levels of total phenols, oxalic acid, ascorbic acid, catalase, peroxidases, polyphenol oxidase, and chlorophyll content index were elevated in groundnut plants infected with stem rot due to increased carbon dioxide levels. The biochemical activity was high at its peak in inoculated plants on 4th and 6th day post-inoculation of the pathogen and gradually declined on 8th and 10th days.

Untargeted Metabolomic Analysis Reveals a Potential Role of Saponins in the Partial Resistance of Pea (Pisum sativum) Against a Root Rot Pathogen, Aphanomyces euteiches.

In soilborne diseases, the plant-pathogen interaction begins as soon as the seed germinates and develops into a seedling. Aphanomyces euteiches, an oomycete, stays dormant in soil and is activated by sensing the host through chemical signals present in the root exudates. The composition of plant exudates may, thus, play an important role during the early phase of infection. To better understand the role of root exudates in plant resistance, we investigated the interaction between partially resistant lines (PI660736 and PI557500) and susceptible pea cultivars (CDC Meadow and AAC Chrome) against A. euteiches during the pre-invasion phase. The root exudates of the two sets of cultivars clearly differed from each other in inducing oospore germination. PI557500 root exudate not only had diminished induction but also inhibited the oospore germination. The contrast between the root exudates of resistant and susceptible cultivars was reflected in their metabolic profiles. Data from fractionation and oospore germination inhibitory experiments identified a group of saponins that accumulated differentially in susceptible and resistant cultivars. We detected 56 saponins and quantified 44 of them in pea root and 30 from root exudate; the majority of them, especially soyasaponin I and dehydrosoyasaponin I with potent in vitro inhibitory activities, were present in significantly higher amounts in both roots and root exudates of PI660736 and PI557500 compared with Meadow and Chrome. Our results provide evidence for saponins as deterrents against A. euteiches, which might have contributed to the resistance against root rot in the studied pea cultivars. [Formula: see text] Copyright © 2024 His Majesty the King in Right of Canada, as represented by the Minister of Agriculture and Agri-Food Canada and the National Research Council of Canada. This is an open access article distributed under the CC BY 4.0 International license.

Assessment of Genetic Diversity for MYMV Resistance in Mungbean [Vigna radiata (L.) Wilczek] using SSR Markers

Background: Mung bean (Vigna radiata L.) is among the most significant edible legume crops and consumed in various parts of the world. Among different biotic factors, mungbean yellow mosaic virus (MYMV) affects this crop. The objective of the present investigation was to assess genetic variability among mungbean genotypes for MYMV resistance using simple sequence repeat markers. Methods: The present research was conducted to assess the genetic diversity among selected mungbean genotypes from field screening of 303 genotypes with an emphasis on resistance against MYMV. The field screening was done at Seed Breeding Farm, College of Agriculture, JNKVV, Jabalpur, Madhya Pradesh during summer 2022, kharif 2022 and summer 2023. Thirty SSR markers have been utilized to measure genetic variation among the 32 studied genotypes. Result: Marker MB-SSR033 stands out as the most informative locus with the greatest PIC and gene diversity value. The cluster analysis, classified the 32 genotypes into two major groups and maximum distance was noted between PDM 139 and IC 314523. The SSR markers CEDG293 (10.14%) and DMBSSR008 (9.11%) were found considerably linked to MYMV resistance. Harnessing multiple sources of resistance gives a good possibility to boost the resistance and production of mungbean cultivars.

Transcriptome Analysis Reveals the Molecular Mechanisms of Carrot Adaptation to Alternaria Leaf Blight

Carrot (Daucus carota L.) is an important vegetable crop that is rich in carotenoids and is widely cultivated throughout the world. Alternaria leaf blight (ALB), caused by infection with Alternaria dauci (A. dauci), is the most serious fungal disease in carrot production. Although several quantitative trait loci associated with ALB resistance have been identified, the genetic mechanisms underlying this resistance remain largely unelucidated. The aim of the present study was to clarify the infection mode of A. dauci and examine the molecular mechanisms underlying carrot cultivar adaptation to ALB by RNA sequencing. Microscopic observation revealed that A. dauci invades leaf tissues by entering through stomata, and resistant germplasms may significantly inhibit the infection and colonization of A. dauci. In addition, transcriptomic analyses were performed to detect the key pathways and genes associated with the differential responses between ALB-resistant (HB55) and ALB-susceptible (14088) carrot cultivars. These results suggest that the secondary metabolic process, phenylpropanoid biosynthesis, and tyrosine metabolism might play important roles in the resistance of carrots to A. dauci. Three candidate genes (LOC108208301, LOC108215577, and LOC108224339) that were specifically upregulated in the resistant carrot cultivar ‘HB55’ after A. dauci infection were identified as the key resistance response genes. These findings provide insights into the resistance mechanism of carrots to ALB, as well as key candidate genes and information on expression regulation for the molecular breeding of carrot disease resistance.

Molecular identification of a Pm4 allele conferring powdery mildew resistance in durum wheat DR88

BackgroundPowdery mildew, caused by Blumeria graminis f. sp. tritici (Bgt), is one of the most destructive wheat diseases worldwide. Durum wheat (Triticum turgidum L. var. durum Desf.) is a crucial gene donor for improving common wheat.ResultsIn this study, we investigated a durum wheat accession, DR88, which exhibits broad and high levels of resistance to powdery mildew. Using bulked segregant RNA-Seq (BSR-Seq), we identified a dominant gene, tentatively designated PmDR88, and localized it to 743–776 Mb interval on chromosome arm 2AL according to the reference genome of durum wheat cv. Svevo. Subsequently, PmDR88 was mapped in a genetic region of 3.9 cM flanked by the markers WGRE77410 and WGRC872 at genetic distances of 1.6 and 2.3 cM, respectively; it also co-segregated with JS717×JS718, the diagnostic marker for the Pm4 locus. Genotyping of a large population comprising 5,174 F2:3 families using JS717×JS718 confirmed that PmDR88 is located at the Pm4 locus on 2AL. Sequence alignment revealed that PmDR88 shares identical amino acid sequences with Pm4d, while qRT-PCR analysis suggested distinct expression patterns for PmDR88 compared with previously reported Pm4 alleles. Two complementary DNA markers, including the dominant co-segregating marker JS717×JS718 and a newly developed closely-linked co-dominant marker WGRE77410, were confirmed to be available for efficiently transferring PmDR88 into the tested wheat backgrounds by marker-assisted selection (MAS) strategy.ConclusionsPmDR88 was mapped in the Pm4 locus. Despite sharing identical amino acid sequences with Pm4d, PmDR88 exhibits distinct expression patterns. Moreover, DR88 shows broad and high levels of resistance to powdery mildew. Two complementary DNA markers were identified for MAS breeding. The molecular identification of PmDR88 will facilitate transfer of this Pm4 allele into susceptible cultivars for resistance improvement or into resistant cultivars for resistance-enhanced pyramiding breeding.

Cell Wall Dynamics in the parasitic plant (Striga) and rice pathosystem.

In the plant-plant pathosystem of rice (Oryza sativa) and the parasitic plant Striga hermonthica, cell walls from either plant are important defensive and offensive structures. Here we reveal cell wall dynamics in both Striga and rice using simultaneous RNA sequencing. We used weighted gene co-expression network analysis (WGCNA) to home in on cell wall modification processes occurring in interactions with a resistant rice cultivar (Nipponbare) compared to a susceptible one (IAC 165). Likewise, we compared the cell wall dynamics in Striga infecting resistant and susceptible rice. Our study revealed an intense battlement at the Striga-rice cell walls involving both parasite (offense) and host (defense) factors; the outcome of which makes the difference between successful or failed parasitism. Striga activates genes encoding cell wall degrading enzymes (CWDEs) to gain access to the host; expansins to allow cell elongation and pectin methyl esterase inhibitors for rigidity during infection. In the susceptible host, immune response processes are not induced and Striga derived CWDEs easily breach the host cell wall resulting in successful parasitism. In contrast, the resistant host invokes immune responses modulated by phytohormones to fortify the cell wall through polysaccharides and lignin deposition. Through these processes, the cell wall of the resistant host successfully obstructs parasite entry. We discuss the implications of these findings in the context of practical agriculture in which cell wall modification can be used to manage parasitic plants.

MATHEMATICAL MODELING AND OPTIMAL CONTROL OF WHEAT STRIPE RUST (Yellow Rust) DISEASE

Wheat Stripe Rust is a devastating fungal disease that is the largest limitation to wheat production and threatens the global food supply. In this work, we proposed a mathematical system of ordinary differential equations to model the wheat Stripe Rust transmission dynamics. First, we showed the feasible region, the positivity of the solution, the model’s equilibrium points and the basic reproduction number. Second, we used the Pontryagin maximum principle to extend the basic system into an optimal control system by embedding three control measures (resistant cultivars, fungicides and cultural practices). Finally, we used a numerical simulation of the optimality system to demonstrate the thorough impacts of resistant wheat cultivars, fungicide treatments and cultural practices in reducing the epidemic.

MEMBRANE PROTEIN 1 encoding an amino acid transporter confers resistance to blast fungus and leaf-blight bacterium in rice.

Amino acid transporters (AATs) have been shown to be involved in immune responses during plant-pathogen interactions; however, the molecular mechanism by which they function in this process remains unclear. Here, we used a joint analysis of a genome-wide association study and quantitative trait locus (QTL) mapping to identify MEMBRANE PROTEIN 1, which acts as a QTL in rice against blast fungus. Heterogeneous expression of OsMP1 in yeast supported its function in transporting a wide range of amino acids, including Thr, Ser, Phe, His, and Glu. OsMP1 could also mediate 15N-Glu efflux and influx in Xenopus oocyte cells. The expression of OsMP1 was significantly induced by Magnaporthe oryzae in the resistant rice landrace Heikezijing, whereas no such induction was observed in the susceptible landrace Suyunuo. Overexpressing OsMP1 in Suyunuo enhanced disease resistance to blast fungus and leaf blight bacterium without resulting in a yield penalty. In addition, the overexpression of OsMP1 led to increased accumulation of Thr, Ser, Phe, and His in the leaves and this contributed to the reduced disease susceptibility, which was associated with up-regulation of the jasmonic acid pathway. Our results demonstrate the important role of OsMP1 in disease resistance in rice and provide a potential target for breeding more resistant cultivars without reducing yield.

Screening Method to Identify Watermelon Cultivars Resistant to Acidovorax citrulli, the Cause of Bacterial Fruit Blotch.

Acidovorax citrulli is a causative pathogen for bacterial fruit blotch (BFB) in Cucurbitaceae, including watermelon. The most effective method to control this plant disease is to cultivate resistant cultivars. Herein, this study aimed to establish an efficient screening method to determine the resistance of watermelon cultivars against A. citrulli. To this end, we explored the virulence of seven A. citrulli isolates belonging to clonal complex group I or II based on gltA gene analysis. Furthermore, we evaluated the BFB occurrence in the seedlings of two arbitrarily selected watermelon cultivars according to the growth stage of the watermelon seedlings, inoculum concentration, and incubation temperature after inoculation in a humidity chamber. Taken together, we established the following method to determine the resistance of watermelon cultivars against A. citrulli: watermelon seedlings at the fully expanded two-leaf stage can be spray-inoculated with an A. citrulli bacterial suspension at a concentration of 1.0 × 106 cfu/ml; after incubation for 48 h at 28℃ in a humidity chamber, the plants were cultivated in a growth chamber at 25℃ with 80% relative humidity under a 12-h light/dark cycle; and BFB occurrence on the plants can be investigated at 7 dpi by visual estimation of the diseased leaf area (%). Based on these experimental methods, we investigated the resistance degree of 43 commercial watermelon cultivars against A. citrulli KACC 17005. Therefore, our results can provide important information for the development of resistant cultivars against A. citrulli.

Evaluating the resistance of some sugar beet cultivars to Cercospora leaf spot

Evaluating the resistance of some sugar beet cultivars to Cercospora leaf spot

Development of rapid, efficient and cost effective screening technique for testing arecanut against Phytophthora meadii incitant of fruit rot disease

To accelerate identification of disease resistant arecanut germplasm or hybrids against Phytophthora, it is very much imperative to develop bioassays which could differentiate resistant and susceptible cultivars efficiently. Here, developed a cost effective and rapid technique called “Detached Leaf Assay” to identify resistant germplasm at the seedling stage itself. Standardized zoospore production in highly virulent Phytophthora meadii (P19) by incubating under 12 hours light and dark regime. Zoospore suspension adjusted to 105spores ml-1 in petri plates. Subsequently, surface sterilized arecanut leaves were floated in zoospore suspension and incubated at temperature of 24±1°C. Disease symptoms, including water-soaked lesions, were recorded three days after inoculation. Infection lesion increased from 1 to 7.3 cm2. The pathogen was re-isolated and confirmed with the original culture. The assay was successfully validated to screen arecanut accessions, wild types and hybrids against P. meadii. This technique is the first to be developed, and it is simple, cost-effective, and faster. It also provides consistent infection and could be effectively utilized to screen arecanut germplasm or hybrids against P. meadii in the seedling stage itself.• Developed a cost effective, efficient and rapid screening technique• The technique was validated to identify resistant genotypes against Phytophthora meadii at the seedling stage.

Transcriptome Comparison between Resistant and Susceptible Soybean Cultivars in Response to Inoculation of Phytophthora sojae.

Phytophthora root and stem rot, caused by Phytophthora sojae, considerably reduces soybean yield worldwide. Our previous study identified two genomic regions on chromosome 18 (2.1-2.6 and 53.1-53.3 Mbp) that confer resistance to the P. sojae isolate 2457, through linkage analysis using progenies derived from the Daepung × Socheong2 population. These two regions contained 51 and 19 annotated genes, respectively. However, the specific gene responsible for resistance to P. sojae isolate 2457 has yet to be identified. In this study, we performed a comparative transcriptomic analysis of Socheong2 and Daepung, two Korean soybean varieties identified as resistant and susceptible to P. sojae isolate 2457, respectively. RNA sequencing was conducted on tissue samples collected at 0, 6, and 12 hours after inoculation (HAI), and significant differences in the expression of defense-related genes were observed across time points and between the two cultivars. Genes associated with the jasmonic acid, salicylic acid, ethylene, and systemic acquired resistance pathways were upregulated in both cultivars at 6 and 12 HAI compared to 0 HAI, with these biological processes were more strongly upregulated in Socheong2 compared to Daepung at 6 and 12 HAI. A comparison of differentially expressed genes (DEGs) and candidate genes within the previously identified QTL regions revealed an ortholog of the HS1 PRO-1 2 gene from Arabidopsis thaliana among the upregulated DEGs in Socheong2, particularly at 12 HAI compared to 0 HAI. This study will aid in targeted breeding efforts to develop soybean varieties with improved resistance to P. sojae.

Effect of temperature and moisture on soil pathogen Fusarium solani of lemon in Adjara, Georgia

The research was conducted in the 2022 and 2023 seasons in the agrometerology and plant protection laboratory and citrus greenhouse of Batumi Shota Rustaveli State University, the aim of which was groupe and unit role of temperature and soil moisture (SM) content on aggressive soil pathogen F. solani on lemon, also effects of pathogen density and soil moisture on belowground and aboveground morphological traits. In our study, we could find that the both temperature and soil moisture played a decisive role in influencing the root rot disease scenario. As per the disease susceptibility index (DSI), a combination of high temperature (35°C) and low SM (60%) was found to elicit the highest disease susceptibility in lemon. High pathogen colonization was realized in lemon root tissue at all time-points irrespective of genotype, temperature, and SM. Interestingly, this was in contrast to the DSI where no visible symptoms were recorded in the roots or foliage during the initial time-points. For each time-point, the colonization was slightly higher at 35°C than 25°C, while the same did not vary significantly with respect to SM. Shoot biomass was not affected by either pathogen density or soil moisture. However, the two experimental factors have additive effects on the severity of leaf damage. Leaf damage increased with the density of F. solani in the soil, being significantly higher at 60 CFU/g and 120 CFU/g than in control seedlings. Leaf damage was higher at the two extreme soil moisture levels (15% and 100% WHC) than at the two intermediate levels (40% and 50%). In addition, differential expression studies revealed the involvement of defense-related genes, such as endochitinase and chitinase, in the resistant lemon cultivar Meyer, which contribute to retarding root rot disease progression in lemon. In the early stages of infection, especially with low SM. That can be beneficial for farmers and researchers who involve in Citrus

Histological Dissection of Fusarium-Banana Interaction Using a GFP-Tagged Subtropical Race 4 Strain of Fusarium oxysporum f. sp. cubense on Banana Cultivars with Differing Levels of Resistance

Fusarium wilt, caused by Fusarium oxysporum f. sp. cubense (Foc), poses a significant threat to global banana production. This study used a GFP-tagged subtropical race 4 strain of Foc (GFP-Foc-STR4) to trace the pathogen’s movement in different banana cultivars. These include a race 4 resistant cultivar FHIA25 and the Cavendish somaclone ‘GCTCV119’, as well as susceptible cultivars including ‘Lady Finger’, ‘FHIA02’, and ‘Williams’ Cavendish. GFP localization revealed that GFP-Foc-STR4 was able to infect all tested cultivars, moving from the roots to the rhizome and aerial parts of the plant. Tyloses formation in root and rhizome vasculature, visualised with GFP autofluorescence and confirmed by scanning electron microscopy, was found to restrict Foc within the xylem vessels, slowing its spread but not fully preventing infection. This containment mechanism contributes to the host tolerance of ‘FHIA25’ and ‘GCTCV119’, though it does not confer complete immunity. The use of the fluorescently tagged Foc strain provides valuable insight into the infection process, and supports efforts in the integrated management of Fusarium wilt of banana.

Control of Cucumber Powdery Mildew Using Resistant Cultivars and Organic Agricultural Materials.

This study evaluated the efficacy of various inorganic materials, biological control agents, organic agricultural materials (OAMs), and essential oils for controlling cucumber powdery mildew (CPM) under greenhouse conditions. Treatments included silicate, bicarbonate, copper sulfate, sulfurbased compounds, Bacillus subtilis KB-401, Bacillus amyloliquefaciens M27, Bordeaux mixtures, chitosan combined with oxidated copper salt, chitooligosaccharides, and essential oils such as castor and rapeseed oil with lecithin. Results demonstrated that Bordeaux mixtures, particularly Bordeaux Mixture I, and sulfur-based compounds provided the most reliable CPM control among inorganic materials. Bacillus strains KB-401 and M27 achieved sustained disease suppression, suggesting their value in integrated pest management (IPM). Chitosan combined with oxidated copper salt showed high efficacy, making it a promising candidate for long-term control. Among OAMs, loess-sulfur mixtures proved especially effective in preventive applications, achieving comparable results to resistant cultivar 'Saronsamcheok'. Essential oils, including castor and rapeseed oil, also exhibited significant CPM suppression potential, although repeated applications may be necessary for sustained control. These findings highlight the potential of these environmentally friendly treatments as viable components of an IPM strategy for managing CPM in cucumber crops. Further studies are recommended to optimize combinations and application timing for enhanced efficacy.

Prediction of olive tuberculosis through physicochemical characterisation of Pseudomonas savastanoi and surfaces of different olive tree parts

ABSTRACT This study examined plant–microbe interactions and surface contamination of olive trees by Pseudomonas savastanoi pv. savastanoi, the pathogen causing olive tuberculosis. Using XDLVO theory, we assessed the theoretical adhesion of P. savastanoi B97 cells to the bark, upper, and lower leaf surfaces of four olive cultivars based on physicochemical properties. Contact angle measurements revealed that lower leaf surfaces were more hydrophobic than upper leaf and bark surfaces, with a stronger electron donor character observed on the latter two. Lower leaf surfaces were identified as the preferred site for bacterial adhesion because of higher hydrophobicity. Among the cultivars, Arbicuina DOC and Arbicuina were most susceptible to colonisation. Conversely, cultivars with lower hydrophobicity and stronger electron donor properties, such as Haouzia and Moroccan Picholine, demonstrated greater resistance. These findings suggest that evaluating these properties can inform disease control strategies, promoting sustainable agriculture through resistant cultivars or targeted management of vulnerable surfaces.

Genetic Insights and Molecular Breeding Approaches for Downy Mildew Resistance in Cucumber (Cucumis sativus L.): Current Progress and Future Prospects

Cucurbit downy mildew, caused by Pseudoperonospora cubensis, is a devastating disease in cucumbers that leads to significant yield losses in many cucurbit-growing regions worldwide. Developing resistant cucumber varieties is a sustainable approach to managing this disease, especially given the limitations of chemical control and the evolving nature of pathogens. This article reviews the genetic basis of downy mildew resistance in cucumbers, emphasizing key resistance (R) genes and quantitative trait loci (QTLs) that have been mapped. Recent advances in molecular breeding tools, including marker-assisted selection (MAS), genomic selection (GS), and CRISPR/Cas9 genome editing, have accelerated the development of resistant cultivars. This review also explores the role of transcriptomics, genomics, and other ‘omics’ technologies in unraveling the molecular mechanisms behind resistance and offers insights into the future of breeding strategies aimed at long-term disease management. Management strategies for cucurbit downy mildew are discussed, along with the potential impacts of climate change on the occurrence and severity of downy mildew, highlighting how changing environmental conditions may influence disease dynamics. Integrating these advanced genetic approaches with traditional breeding promises to accelerate the development of downy mildew-resistant cucumber varieties, contributing to the sustainability and resilience of cucumber production.

Defense-related enzymes associated with resistance to onion Fusarium basal rot

This study was carried out to quantify changes in the activities of antioxidative enzymes such as catalase (CAT), peroxidase (POX) and superoxide dismutase (SOD) in two resistant onion cultivars 'Saba - HS' and 'Saba' and two susceptible cultivars 'Golden Eye' and 'Savannah Sweet' following an inoculation with Fusarium oxysporum f. sp. cepae (FOC) at seedling stage. Further, we assessed the expression of transcription factors (TFs), R1, PR5 and RGA29-genes that are involved in conferring resistance post-inoculation using qRT-PCR. The results revealed that the least disease severity occurred with the resistant 'Saba - HS' (4.7%) and 'Saba' (6.7%) cultivars, whereas the highest disease severity occurred with the susceptible 'Golden Eye' (89.6%) and 'Savannah Sweet' (88.9%) cultivars, respectively. Both resistant genotypes 'Saba' and 'Saba-HS' showed a significant increase in CAT, POX, and SOD activities at a transcriptional level. CAT activity was upregulated 4.81-fold in 'Saba' and 4.22-fold in 'Saba-HS' followed by POX where 'Saba' showed an increase by 3.53-fold and 'Saba-HS' by 2.35-fold, and SOD 'Saba' 17.46-fold and 'Saba-HS' 22.95-fold, relatively. Marker genes, RGA29, R1 and PR5, were also upregulated in the resistant-genotypes by 3.83, 4.78 and 5.01-fold, in comparison to their-controls, respectively. Similar trends were recorded for the biomass growth parameters (BGPs).

Application of Liquid Chromatography-Ion Mobility Spectrometry-Mass Spectrometry-Based Metabolomics to Investigate the Basal Chemical Profile of Olive Cultivars Differing in Verticillium dahliae Resistance.

The limited effectiveness of current strategies to control Verticillium wilt of olive (VWO) prompts the need for innovative approaches. This study explores the basal metabolome of 43 olive cultivars with varying resistance levels to Verticillium dahliae, offering alternative insights for olive crossbreeding programmes. The use of an innovative UHPLC-ESI-TimsTOF MS/MS platform enabled the annotation of more than 70 compounds across different olive organs (root, stem, and leaf) and the creation of a preliminary compilation of TIMSCCSN2 experimental data for more reliable metabolite annotation. Moreover, it allowed the documentation of numerous isomeric species in the studied olive organs by resolving hidden compounds. Multivariate statistical analyses revealed significant metabolome variability between highly resistant and susceptible cultivars, which was further investigated through supervised PLS-DA. Key markers indicative of VWO susceptibility were annotated and characteristic compositional patterns were established. Stem tissue exhibited the highest discriminative capability, while root and leaf tissues also showed significant predictive potential.