Foot and root rot, caused by a complex of soil-borne fungal and oomycete pathogens, including several Fusarium spp., can cause serious yield losses in faba bean. Current control strategies rely largely on agronomic practices and limited varietal resistance. Identifying novel sources of genetic resistance is of great potential value for breeding elite varieties with improved foot rot resistance. A partially resistant Vicia faba accession '[ig124213][1]' (NV490) was crossed with a moderately susceptible '[ig124301][2]' (NV512) and a mapping population comprising 198 F3 families was developed. This was screened for resistance to a mixture of seven UK field isolates of Fusarium avenaceum and Fusarium oxysporum under glasshouse conditions. Several F3 families with moderate to high levels of resistance to both Fusarium species were identified, and a high-density linkage map of the V. faba genome including 6755 SNP-markers in seven linkage groups (LG) was generated using the 'Vfaba_v2' Axiom SNP array. Quantitative trait loci associated with improved resistance to Fusarium foot and root rot were identified, including one major QTL on LG4, corresponding to the chromosome 4 of V. faba. ### Competing Interest Statement The authors have declared no competing interest. [1]: /lookup/external-ref?link_type=GEN&access_num=ig124213&atom=%2Fbiorxiv%2Fearly%2F2025%2F02%2F25%2F2025.02.21.639454.atom [2]: /lookup/external-ref?link_type=GEN&access_num=ig124301&atom=%2Fbiorxiv%2Fearly%2F2025%2F02%2F25%2F2025.02.21.639454.atom

IntroductionChocolate spot, caused by the ascomycete fungus Botrytis fabae, is a devastating foliar disease and a major constraint on the quality and yield of faba beans (Vicia faba). The use of fungicides is the primary strategy for controlling the disease. However, high levels of partial genetic resistance have been identified and can be exploited to mitigate the disease.MethodsThe partially resistant V. faba cultivar Maris Bead and susceptible Egyptian accession ig70726 were crossed, and a genetic mapping population of 184 individuals was genotyped in the F2 generation and screened for resistance to B. fabae infection in the F3, F5, and F6 generations in a series of field experiments. A high-density linkage map of V. faba containing 3897 DArT markers spanning 1713.7 cM was constructed.ResultsMultiple candidate quantitative trait loci (QTLs) in 11 separate regions of the V. faba genome were identified; some on chromosomes 2, 3, and 6 overlapped with loci previously linked to resistance to Ascochyta leaf and pod blight caused by the necrotrophic fungus Ascochyta fabae. A transcriptomics experiment was conducted at 18 h post-inoculation in seedlings of both parents of the mapping population, identifying several differentially expressed transcripts potentially involved in early stage defence against B. fabae, including cell-wall associated protein kinases, NLR genes, and genes involved in metabolism and response to reactive oxygen species.DiscussionThis study identified several novel candidate QTLs in the V. faba genome that contribute to partial resistance to chocolate spot, but differences between growing seasons highlighted the importance of multi-year phenotyping experiments when searching for candidate QTLs for partial resistance.

We have sequenced the genome of grass pea ( Lathyrus sativus ), a resilient diploid (2n=14) legume closely related to pea ( Pisum sativum ). We determined the genome size of the sequenced European accession (LS007) as 6.3 Gbp. We generated two assemblies of this genome, i) EIv1 using Illumina PCR-free paired-end sequencing and assembly followed by long-mate-pair scaffolding and ii) Rbp using Oxford Nanopore Technologies long-read sequencing and assembly followed by polishing with Illumina paired-end data. EIv1 has a total length of 8.12 Gbp (including 1.9 billion Ns) and scaffold N50 59,7 kbp. Annotation has identified 33,819 high confidence genes in the assembly. Rbp has a total length of 6.2 Gbp (with no Ns) and a contig N50 of 155.7 kbp. Gene space assessment using the eukaryote BUSCO database showed completeness scores of 82.8 % and 89.8%, respectively.

Abstract In order to gain an understanding of the genetic basis of traits of interest to breeders, the pea varieties Brutus, Enigma and Kahuna were selected, based on measures of their phenotypic and genotypic differences, for the construction of recombinant inbred populations. Reciprocal crosses were carried out for each of the three pairs, and over 200 F2 seeds from each cross advanced to F13. Bulked F7 seeds were used to generate F8–F11 bulks, which were grown in triplicated plots within randomized field trials and used to collect phenotypic data, including seed weight and yield traits, over a number of growing seasons. Genetic maps were constructed from the F6 generation to support the analysis of qualitative and quantitative traits and have led to the identification of four major genetic loci involved in seed weight determination and at least one major locus responsible for variation in yield. Three of the seed weight loci, at least one of which has not been described previously, were associated with the marrowfat seed phenotype. For some of the loci identified, candidate genes have been identified. The F13 single seed descent lines are available as a germplasm resource for the legume and pulse crop communities.

There is now a wide range of diagnostic tools in the armoury to help prevent or control damaging disease outbreaks. When applied in the context of biosecurity, they have immense power to protect the plants on which food, feed, fuel and fibre supplies rely. Diagnoses which used to rely on culturing organisms, examining spores, or testing viruses on indicator plants, often taking many weeks to complete, can now be achieved in a matter of hours. Moreover, the advent of in-field diagnostic tests allows growers, agronomists or plant health and seeds inspectors to get a reliable test result without sending a sample to a laboratory. Remote sensing, using ground vehicles, unmanned aerial vehicles, or satellite technology, can bring a new dimension to surveillance, detection and diagnostic systems. Pathogen variation can be characterised rapidly by molecular marker techniques, potentially accelerating the process of identifying new pathotypes or fungicide resistant strains which threaten plant productivity. Metagenomic methods will undoubtedly play a part in non-targeted diagnostics, and identifying new threats to biosecurity. While diagnostic methods have advanced rapidly, their use in disease management in the field must be supported by robust sampling methods, treatment thresholds, and in depth understanding of disease risks.

Agricultural and natural plant systems within the European Union are diverse, widely distributed, and vulnerable to the introduction of new pests and pathogens. Detection, surveillance and diagnosis are all necessary to ensure effective protection of crops and foods from pathogen incursions resulting from natural or intentional introductions. Each EU nation relies upon a cadre of specialized plant health experts operating within an administrative framework that is unique to that country. However, since the movement of pathogens and pests is influenced more by weather patterns and human activities such as trade and travel than by politics and boundaries, communication among plant health specialists across EU national borders would facilitate informed preparations and decision-making to minimize the impacts of invasive pathogens. A web-based plant diagnostic information system and plant disease and pest database were designed and implemented for deployment within the European Union. This system, designated the EU Plant Diagnostic Information System (EUPDIS), evolved from consideration of the features of other systems, particularly the National Plant Diagnostic Network (NPDN) deployed in the USA, from considerations of the needs of EU plant health practitioners and plant protection officers, and the recognition of the need for a system that alerts neighbouring countries of emerging threat situations outside their own borders. Increasing free trade agreements will ensure the continued movement of pests and pathogens across borders and regions. Early detection and rapid response are essential to minimize the economic and environmental impacts from these introductions. A virtual EU Plant Diagnostic Network supported by a comprehensive diagnostic information system such as EUPDIS will provide the platform necessary to facilitate the collaboration and cooperation required to protect plant systems. The main features of the system, data collection, data reporting and disease identification assistance are described along with the rationale for the data collection and dissemination deployed.

Background and Aims Gene flow from crops to their wild relatives has the potential to alter population growth rates and demography of hybrid populations, especially when a new crop has been genetically modified (GM). This study introduces a comprehensive approach to assess this potential for altered population fitness, and uses a combination of demographic data in two habitat types and mathematical (matrix) models that include crop rotations and outcrossing between parental species. Methods Full life-cycle demographic rates, including seed bank survival, of non-GM Brassica rapa × B. napus F1 hybrids and their parent species were estimated from experiments in both agricultural and semi-natural habitats. Altered fitness potential was modelled using periodic matrices including crop rotations and outcrossing between parent species. Key Results The demographic vital rates (i.e. for major stage transitions) of the hybrid population were intermediate between or lower than both parental species. The population growth rate (λ) of hybrids indicated decreases in both habitat types, and in a semi-natural habitat hybrids became extinct at two sites. Elasticity analyses indicated that seed bank survival was the greatest contributor to λ. In agricultural habitats, hybrid populations were projected to decline, but with persistence times up to 20 years. The seed bank survival rate was the main driver determining persistence. It was found that λ of the hybrids was largely determined by parental seed bank survival and subsequent replenishment of the hybrid population through outcrossing of B. rapa with B. napus. Conclusions Hybrid persistence was found to be highly dependent on the seed bank, suggesting that targeting hybrid seed survival could be an important management option in controlling hybrid persistence. For local risk mitigation, an increased focus on the wild parent is suggested. Management actions, such as control of B. rapa, could indirectly reduce hybrid populations by blocking hybrid replenishment.

Genetically modified (GM) crops will have impacts on agriculture and both the agricultural and natural environment. Analysing the consequences for the agricultural environment requires study of the characteristics of the GM crop and its hybridising relatives, and study of the management systems involved in growing the GM crop and other crops grown in rotation with it. GM crops may also have impacts on uncultivated land and natural environments. Thus risk assessments are concentrating on whether the genetically modified characteristics of a GM crop are likely to change the behaviour of the plants in their environments to the extent that ecological balances are altered. This paper discusses approaches to risk assesments and reviews results of risk assessments of GM Brassica crops.

The environmental and agronomic impact of genetically modified (GM) herbicide tolerant oilseed rape has been studied by NIAB since 1995. This paper reports on results of gene flow frequencies recorded between trial plots at several National List sites and at a large scale release of genetically modified herbicide tolerant rape in. the UK. Levels of cross pollination tended to decrease with increasing distance from the pollen source, there was some evidence of varietal differences in receptiveness to foreign pollen. Pollen dispersal was also recorded at distances of up to 400m from a large release of GM herbicide tolerant rape using male sterile 'bait' plants.

Results from monitoring the incidence and persistence of genetically modified (GM) oilseed rape volunteers at National List sites and at eight large scale release sites throughout the UK show that volunteer numbers in subsequent crops can vary considerably from site to site. At some sites volunteers were fully controlled in subsequent crops. At other sites viable GM seeds persisted in the soil, producing volunteer populations for up to three years after the release. Where GM and non GM varieties were grown together, the proportion of transgenic volunteers in subsequent crops appears to be lower than the original percentage grown. Initial results from this study suggest that weediness and invasiveness of oilseed rape volunteers is not enhanced by the specific genetic modifications studied.