Search

Phenotyping data of legumes-cereals intercrops under field conditions at Córdob-Spain during two consecutive seasons 2021-2022 and 2022-2023.

Characterization data of a Vicia faba germplams collection grown at Córdoba, Spain at three sites during 2022 and 2023.

Faba bean (Vicia faba) is a temperate grain legume of major importance for food and feed. Powdery mildews are an important group of diseases in many crops, although in faba bean, it is still considered to be of only minor and local relevance. Here, we report the occurrence of powdery mildew in southern Spain, which was identified through ITS sequencing as Erysiphe trifolii. Resistance screenings allowed the identification of a wide range of responses to the disease, with accessions BPL-710 and ILB-4708 outstanding due to their high levels of resistance. Histological studies showed that the mechanisms of resistance may involve the inhibition of germination and impairment of fungal development, as shown by a limited number of primary and secondary hyphae compared to those of the susceptible accessions. This work permitted a better understanding of the interaction of faba bean and powdery mildew, laying the ground for breeding programs for resistance if needed in the future.

Uromyces viciae-fabae is a highly specific biotrophic fungus that causes faba bean rust, one of the major diseases affecting this crop. We have assessed the feasibility of using intercropping (faba bean mixed with either pea, wheat or barley) or mixtures of susceptible and resistant cultivars to control rust both under field and controlled conditions. The results of four field intercropping experiments showed a significant reduction in rust severity on faba bean when intercropped with barley (average 22% reduction) but not with the other combinations. This reduction was also confirmed in studies under controlled conditions. The barrier effect of barley appears as the main mechanism explaining rust suppression. Additional experiments under controlled conditions showed that intercropping with barley did not influence the N content of faba bean and that different levels of N nutrition had no impact on rust severity in any case. The cultivar mixture field experiments showed that rust severity in the susceptible cultivar decreased as the proportion of the resistant cultivar in the mixture increased. The importance of the barrier effect of the resistant cultivars was determined in an experiment under controlled conditions. It can be concluded that crop diversification offers great potential to reduce rust in faba bean.

Chocolate spot, which is caused by the necrotrophic fungus Botrytis fabae, is a major foliar disease occurring worldwide and dramatically reducing crop yields in faba bean (Vicia faba). Although chemical control of this disease is an option, it has serious economic and environmental drawbacks that make resistant cultivars a more sensible choice. The molecular mechanisms behind the defense against B. fabae are poorly understood. In this work, we studied the leave proteome in two faba bean genotypes that respond differently to B. fabae in order to expand the available knowledge on such mechanisms. For this purpose, we used two-dimensional gel electrophoresis (2DE) in combination with Matrix-Assisted Laser Desorption/Ionization (MALDI-TOF/TOF). Univariate statistical analysis of the gels revealed 194 differential protein spots, 102 of which were identified by mass spectrometry. Most of the spots belonged to proteins in the energy and primary metabolism, degradation, redox or response to stress functional groups. The MS results were validated with assays of protease activity in gels. Overall, they suggest that the two genotypes may respond to B. fabae with a different PSII protein repair cycle mechanism in the chloroplast. The differences in resistance to B. fabae may be the result of a metabolic imbalance in the susceptible genotype and of a more efficient chloroplast detoxification system in the resistant genotype at the early stages of infection.

Cereal-legume intercropping can increase yields, reduce fertilizer input and improve soil quality compared with pure culture. Designing intercropping systems requires the integration of plant species trait selection with choice of crop configuration and management. Crop growth models can facilitate the understanding and prediction of the interactions between plant traits, crop configuration and management. However, currently no existing crop growth model has been calibrated and tested for cereal-legume intercrops throughout Europea. We calibrated the Agricultural Production Systems sIMulator (APSIM) for pure cultures of wheat and faba bean using data from Dutch field trials, and determined the phenological parameters to simulate pure cultures and intercrops from seven field experiments across Europe. APSIM successfully reproduced aboveground dry matters and, for wheat only, grain yields in pure cultures. In intercrops, APSIM systematically overestimated the aboveground dry matter and grain yield of faba bean and underestimated those of wheat. APSIM was reasonably capable of simulating plant heights in pure cultures, but respectively overestimated and underestimated the height of faba bean and wheat in intercrops. In order to simulate wheat-faba bean intercrops better, APSIM should be improved regarding the calculation of biomass partitioning to grains in faba bean and of height growth in both species.

Pea is a temperate grain legume cultivated worldwide that can be severely constrained by powdery mildew infection. Control by fungicides and the use of resistant cultivars is possible, but there is a growing interest in alternative control methods such as crop diversification, particularly in low input agriculture. The aim of this work was to assess the potential of intercropping pea with other crops and of pea cultivar mixtures for powdery mildew management on pea crop. Results show a reduction of powdery mildew on pea when intercropped by replacement at a 50:50 ratio with barley or with faba bean, but not when intercropped with wheat. A barrier effect seems to explain a major part of this decrease, especially in the pea/barley intercrop. This hypothesis was further supported by inoculated seedlings under controlled conditions, where powdery mildew infection on pea decreased with the distance to the inoculation point, this decrease being larger in the intercrop with barley than in the intercrop with wheat and in the pea monocrop. Powdery mildew was also reduced in the mixture of resistant and susceptible cultivars, with infection decreasing with the increasing proportions of the resistant one. Overall, this work shows that crop diversification may be a good strategy to reduce powdery mildew in pea.

Faba bean plays a key role in sustainable agriculture, given its ability to fix nitrogen. Rust is one of the most important diseases affecting faba bean. It is caused by the biotrophic fungus Uromyces viciae-fabae, whose windborn spores infect all aerial parts of the plant. The high economic and environmental cost of fungicides, and the scarcity of resistant cultivars adapted to the different agronomic situations make necessary to find alternatives for rust control. Crop diversification has been proposed as a sound option for disease management (Boudreau, 2013). We studied the potential for rust management in faba bean intercrops and in cultivar mixtures. First, we carried out four intercropping field trials across 3 years in two locations each one consisting of faba bean intercropped at 50% proportion either with wheat, barley or pea, in an alternate replacement system. Second, we performed four cultivar mixture field trials in which a resistant and a susceptible faba bean cultivars were mixed at different proportions (0–100, 25–75, 50–50, 75–25 and 100–0). A significant reduction of rust infection was recorded on faba bean when intercropped with barley but not when intercropped with wheat or with pea. Rust was also significantly reduced in cultivar mixtures, the reduction increasing with the proportion of the resistant cultivar in the mixture. Based on these results, additional experiments were performed on faba bean intercropped with barley seedlings inoculated under controlled conditions. Results confirmed rust reduction and suggested a barrier effect by barley as an important mechanism explaining that reduction. To further investigate the mechanisms behind disease reduction the combined effects of intercropping and nitrogen fertilization on rust disease will be assessed by experiments under controlled conditions.

Cereal-legume intercropping can increase yields, reduce fertilizer input and improve soil quality compared with pure culture. Designing intercropping systems requires the integration of plant species trait selection with choice of crop configuration and management. Crop growth models can facilitate the understanding and prediction of the interactions between plant traits, crop configuration and management. However, currently no existing crop growth model has been calibrated and tested for cereal-legume intercrops throughout Europea. We calibrated the Agricultural Production Systems sIMulator (APSIM) for pure cultures of wheat and faba bean using data from Dutch field trials, and determined the phenological parameters to simulate pure cultures and intercrops from seven field experiments across Europe. APSIM successfully reproduced aboveground dry matters and, for wheat only, grain yields in pure cultures. In intercrops, APSIM systematically overestimated the aboveground dry matter and grain yield of faba bean and underestimated those of wheat. APSIM was reasonably capable of simulating plant heights in pure cultures, but respectively overestimated and underestimated the height of faba bean and wheat in intercrops. In order to simulate wheat-faba bean intercrops better, APSIM should be improved regarding the calculation of biomass partitioning to grains in faba bean and of height growth in both species.

The intercropping of two or more crop species on the same piece of land at a given time has been hypothesized to enhance crop yield stability. To address this hypothesis, we assessed the grain yield stability of various barley-pea and wheat-faba bean mixtures grown in seven experimental field trials (locations) across Europe during two years with contrasting weather (2017 and 2018). Three different yield stability measures were used, all based on the expected yield variability of the mixture components grown as sole crops, and the corresponding observed yield variability of the same components grown in 50:50 mixtures in a replacement design. Stability indices were calculated as ratios between the expected and observed variabilities, with values > 1 indicating greater stability of the intercrops. Mean grain yields tended to be higher in intercrops than sole crops. However, in contrast to our hypothesis, the observed (intercrop) yield stability was similar or lower than the expected (sole crop) stability in most locations except one. Furthermore, yield stability significantly increased with increasing mean yields when assessed across differentially productive locations. The results are relevant for the designing of intercropping systems as a means to increase yield stability and the resilience of cropping systems.

Cereal-legume intercropping can increase yields, reduce fertilizer input and improve soil quality compared with pure culture. Designing intercropping systems requires the integration of plant species trait selection with choice of crop configuration and management. Crop growth models can facilitate the understanding and prediction of the interactions between plant traits, crop configuration and management. However, currently no existing crop growth model has been calibrated and tested for cereal-legume intercrops throughout Europea. We calibrated the Agricultural Production Systems sIMulator (APSIM) for pure cultures of wheat and faba bean using data from Dutch field trials, and determined the phenological parameters to simulate pure cultures and intercrops from seven field experiments across Europe. APSIM successfully reproduced aboveground dry matters and, for wheat only, grain yields in pure cultures. In intercrops, APSIM systematically overestimated the aboveground dry matter and grain yield of faba bean and underestimated those of wheat. APSIM was reasonably capable of simulating plant heights in pure cultures, but respectively overestimated and underestimated the height of faba bean and wheat in intercrops. In order to simulate wheat-faba bean intercrops better, APSIM should be improved regarding the calculation of biomass partitioning to grains in faba bean and of height growth in both species.

Cereal-legume intercropping can increase yields, reduce fertilizer input and improve soil quality compared with pure culture. Designing intercropping systems requires the integration of plant species trait selection with choice of crop configuration and management. Crop growth models can facilitate the understanding and prediction of the interactions between plant traits, crop configuration and management. However, currently no existing crop growth model has been calibrated and tested for cereal-legume intercrops throughout Europea. We calibrated the Agricultural Production Systems sIMulator (APSIM) for pure cultures of wheat and faba bean using data from Dutch field trials, and determined the phenological parameters to simulate pure cultures and intercrops from seven field experiments across Europe. APSIM successfully reproduced aboveground dry matters and, for wheat only, grain yields in pure cultures. In intercrops, APSIM systematically overestimated the aboveground dry matter and grain yield of faba bean and underestimated those of wheat. APSIM was reasonably capable of simulating plant heights in pure cultures, but respectively overestimated and underestimated the height of faba bean and wheat in intercrops. In order to simulate wheat-faba bean intercrops better, APSIM should be improved regarding the calculation of biomass partitioning to grains in faba bean and of height growth in both species.

Introducing diversification in the intensive monocropping systems is an essential requirement to achieve a sustainable agriculture. Plant mixtures are a useful tool to bring about diversification and choosing the right components of those mixtures is key to succeed in this strategy. Legumes are a good component for plant mixtures, especially for their ability to enrich the fertility of the soil. They can be an ideal partner for cereals, both for their complementary ecological behavior and for adding highvalue vegetal protein to the final harvested product. In the frame of past FP6-GLIP and FP7-LEGATO projects we were involved in a series of cereal/legume intercropping experiments to study their effects reducing pests, diseases and weeds. Currently, in the frame of H2020-DIVERSify, among other activities, we are assessing yield benefits. We describe here experiments performed in Almodóvar del Río, Córdoba, started in season 2017-18. In one of them wheat was combined with faba bean and in the other one barley was combined with pea. In each of them, two cultivars of each crop were used in all possible combinations in a randomized block design with four replications. Proportion of crops in both cases was 50/50. Plot size was 1.2 x 10 m. Results from first year on the wheat/faba bean mixture pointed to an increase of up to 20% in faba bean yield, no effecting wheat yield. On the contrary, in the barley/pea mixture, the pea yield was reduced, while barley remains unaffected. This suggests that the proportion of pea should be increased in the mixture, what is being tested this second season. No reduction was observed on Septoria blotch on wheat, or on net blotch on barley. Trials are being repeated for a second season, paying attention also to weed, pest and disease suppression.

During 2016–2017 distribution patterns of pea aphids (Acyrthosiphon pisum) and predatory ground beetles (Carabidae) and the spatio-temporal associations between the two groups of insects were analysed in field pea monocrops and in field pea / barley intercrops. The objectives of the large plot trials were to find out if there are some differences in patterns of spatio-temporal distributions of the aphids and the carabids in the compared crops and if the spatio-temporal associations between the pest and the predator distributions can be influenced by the plant diversity in crops. The spatial patterns of insect counts (aphids, carabids –assessed totally and separately for the individual species) were analysed using SADIE. The tendency towards significant spatio-temporal association (p<0.025) between distribution of aphids and the four important species of carabids were recorded in intercrops even monocrops in some dates. It indicates that these species should play important role in diminishing of aphid populations during their development in crops because they were actively looking for the zones with higher abundances of aphids (at these places the probability that aphids fall down is higher). At the same time in some cases decreases in aphid populations were recorded at the zones in crops where previously higher abundances of carabids were recorded (significant spatial dissociation in their distributions; p>0.975). That shows some species (especially Poecilus cupreus, Pterostichus melanarius, Pseudoophonus rufipes and P. griseus) should play important role in diminishing of aphid populations during their development in crops and can serve as effective biological agents.

During 2014 –2017 distribution patterns of pea aphids and larvae of syrphids (aphid predators) and the spatio-temporal associations between the two groups of insects were analysed in large plots of field pea monocrops vs. pea/barley intercrops. The objectives were tofind out if there are some differences in the patterns of the pest and its predator distributions in the crops and if the spatio-temporal associations between the pest and its predator are influenced by the presence of cereal accompany. The spatial patterns of insect counts were analysed using SADIE. To compare two distributions (aphids vs. syrphids) in the crops, SADIE -Quick Association was used. In intercrops pea aphids and, in part, syrphids showed a strong tendency towards aggregation on dates when the highest abundances of aphids were recorded. In monocrops these tendencies were not recorded. There was a tendency towards somewhat higher spatio-temporal association between aphids and syrphids in intercrops. In intercrops the distributions of aphids measured at the time of their highest abundance were also more spatially related to the subsequent (measured later) distributions of their predator. This indicates more effective localizing of the host by its predator in intercrops. Significant spatial dissociations between syrphids and subsequent (measured later) distribution of aphids were more frequent in intercrops, too. The spatial dissociation should indicate effective predation induced by syrphids in intercrops. Stronger and more spatially and temporally linked relations between the pest and its predator may explain earlier decline of aphid populations usually recorded in legumes intercropped with cereals.

During 2014 –2017 distributions and abundances of B. pisorum eggs and infested seeds were analysed in field pea crops with different structure: pea monocrop (v. Protecta), pea monocrop founded as a combination of two varieties (Protecta with delayed start of flowering + Cisterski with early start of flowering –the second one sown in 6 m wide strips located along edges with Protecta), pea monocrop founded as a combination of the same two varieties –Cisterski sown in 3 m wide strips located along the plot edges and among the 16 m wide strips with Protecta and field pea/barley (Protecta/Sirael –60/40) intercrop. In general the levels of seed infestation were not significantly lower in pea/barley intercrops than in Protecta monocrops. In plots where the two field pea varieties were combined, strong tendency for aggregation of eggs into the zones with Cisterski was recorded. This tendency was more pronounced in the plots where Cisterski was sown in 6 m wide strips along the plot edges. The seeds of Protecta harvested from the plots containing strips of Cisterski were significantly less infested than the seeds from Protecta monoculture even the seeds harvested from pea/barley intercrop in 2014 –2016. When margins with the early variety show width of 6 m and the delay in the start of flowering of the main variety (the variety which occupies the inner part of field) is at least 10 days, the majority (90 % or more) of B. pisorum females lay their eggs on plants located at the margins.

Limited biodiversity is a problem of modern agriculture. The generalization of intensive monocrops has entailed a loss of biological richness in agricultural ecosystems, which has originated several problems, such as reduced soil fertility or a higher incidence of pests and diseases. Two strategies to introduce diversification in our agricultural systems are intercropping, by mixing different crops in the same field, or varietal mixtures, i.e., growing together different varieties of the same crop. In the frame of LEGATO project we have tested during three field seasons both strategies to control two important diseases of grain legumes: rust in faba bean and powdery mildew in pea. In the case of intercropping, the main crop (faba bean or pea) was mixed with either one of two cereals (wheat and barley) or another legume (pea or faba bean). As for varietal mixtures, the experimental design consisted of mixing different proportions of a resistant monogenic variety with a susceptible one Alternate-row mixing was the system employed in both experiments. Results point to a significant reduction of the incidence of both diseases in the intercropped treatments compared to that of the monocrop. Both in the case of rust in faba bean and powdery mildew in pea the best results are obtained when the legume is combined with barley. Varietal mixtures also achieve an important reduction in the levels of both diseases in the susceptible variety. A proportion of 50/50 (resistant/susceptible) appears to be the most efficient combination, balancing adequately disease suppression and increase of genetic variability.

Among the different fungal diseases that affect faba bean, chocolate spot incited by Botrytis fabae is one of the most important, causing in many cases significant yield reductions, being particularly damaging when high relative humidity and mild temperatures concur. Control by fungicides is possible, but it is not environmentally and economically efficient. The employment of resistant varieties appears as the best option. In the last years we have developed a comprehensive breeding program with the main objective of obtaining cultivars combining resistance to chocolate spot and adaptation to Mediterranean environments. This included screening large germplasm collections both in seedlings under controlled conditions and in adult plants in the field over a series of seasons and locations. Identified resistances were introduced in our breeding program and progenies selected for combined resistance and productivity. As a result of this process, now we have available a set of advanced breeding materials. A cultivar has already been submitted for registration and some more are in the offing. In addition to these applied breeding activities we are approaching genetic studies and have developed a recombinant inbred line (RIL) population that has been properly phenotyped over several seasons and genotyped using DArT-Sea marke rs to identify quantitative traits loci (QTLs) related to resistance. These results will be presented and critically discussed.

Chocolate spot, caused by the necrotrophic fungus Botrytis fabae is an important disease affecting faba bean in many regions of the world where it is cultivated. Although chemical control is an option, it presents serious drawbacks in terms of economic and environmental costs, being the use of resistant varieties a better and more efficient alternative. Varying levels of resistance have been previously identified. In this study we used a proteomic approach (2-DE coupled to MALDI-TOF/TOF analysis) to compare the leaf proteome of three faba bean genotypes showing different resistance response to B. fabae. Multivariate statistical analysis identified 270 differential protein spots when genotypes and treatments (non-inoculated and inoculated) were compared, with a total of 89 proteins identified using a combination of peptide mass fingerprinting (PMF) and MSMS fragmentation. Interestingly a high proportion of identified proteins (13%) were proteases, suggesting that protein degradation might play an important role during pathogen infection. Results will be presented and critically discussed in terms of differences between genotypes in response to B. fabae.

Peas and faba beans, as any other crops, can be damaged by a number of diseases. Breeders have explored a range of strategies to exploit available resistances, that unfortunately use to be scarce, incomplete and of limited heritability. As a result, only cultivars with moderate levels of resistance are available to farmers in most instances. This is further complicated by the fact that several clearly distinct species (i.e. Orobanche crenata and O. foetida; Uromyces viciae-fabae and U. pisi; Erysiphe pisiand E. trifolii) can infect the same legume crop. Here we will revise current status of resistance in pea and faba bean to a number of fungal diseases and parasitic weeds discussing historic and recent achievements, with a special focus on potential durability.

Broomrapes are weedy root parasitic plants that severely constraint faba bean (Vicia faba) production in Mediterranean basin. The most widely distributed species affecting faba bean is Orobanche crenata, although O. foetida and Phelipanche aegyptiaca are of local importance. Extensive and long efforts have been made by breeders, but unfortunately only moderately resistant cultivars are available to farmers. Here we summarize a series of experiments intending to characterize the resistance mechanisms involved in accessions with varying levels of resistance earlier reported. In a first rhyzotron experiment we studied the responses of six faba bean accession against O. crenata, O. foetida and P. aegyptiaca. A proportion of broomrape radicles successfully contacting faba bean roots might later become necrotic and fail the tubercle development against a Spanish O. crenata population. Formed broomrape tubercles might later become necrotic, mainly in the case of some of the resistant faba bean accessions to the Spanish O. crenata and to P. aegyptiaca but not to a Syrian O. crenata or to O. foetida. There was little effect on induction of seed germination. In an attempt to go deeper in the germination step a separate series of experiments was performed with other accessions allowing the identification of accessions inducing low germination of O. crenata, O. foetida and P. aegyptiaca, a mechanism that we consider most promising and we are combining with the other ones in our breeding program.

Weed competition hampers the growth of crops and may bring about important yield reductions. Chemical control with herbicides is the most used solution although it entails several problems, such as the appearance of weed resistances to herbicide molecules, environmental damages or high economic costs for farmers. Intercropping may be an efficient alternative to herbicides for weed control. The introduction of another crop in the field increases biodiversity and may result in reduced levels of weed infestation. In the frame of LEGATO project we tested weed reduction in faba bean intercropped with different crops during three consecutive field seasons at Córdoba. The crops introduced were wheat, barley and pea, employing an alternate-row system. Three different experiments were carried out: in one of them replacement intercropping (where rows of the second crop replace rows of the main crop) was chosen; in another one, addition cropping (with rows of the second crop being sown in between the rows of the main crop) was employed; and in a third one, both methods, addition and replacement intercropping, were studied. Results have shown that addition intercropping achieves important reductions of weed coverage and biomass compared to faba bean sole-crop, being barley the most effective companion crop for weed reduction, followed by wheat and pea in decreasing order. On the contrary, no weed reduction was observed in replacement intercropping.

Modern agriculture based on monocultures suffers from a lack of biodiversity. Increasing the diversity of crop systems offers opportunities to improve yield stability, reduce pest and disease damage, and to enhance stress resilience in agricultural systems.

Legume crops, such as pea and faba bean, can be damaged by a number of diseases, but insufficient levels of host resistance are available in most instances. As a result, only cultivars with moderate levels of resistance are available to farmers. Two important groups of diseases are caused by distinct groups of biotrophic pathogens: parasitic weeds (the broomrapes) and airborne fungi (the powdery mildews). Several clearly distinct species of these pathogens are known (the broomrapes Orobanche crenata, O. foetida and O. aegyptiaca; or the powdery mildews Erysiphe pisi and E. trifolii). These pathogens can infect the same legume crops. Historic and recent achievements are reviewed for pea and faba bean, and compared with those experienced in other non-legume crops. Implications in resistance breeding will be critically discussed, with a special focus on potential durability of host resistance.

Ascochyta and Botrytis species cause major diseases on legume crops. Fungi from both genera are well known phytotoxins producers. Based on collaboration between CSIC and Univ. Naples necrotrophic effectors produced by Didymella pinodes and Botrytis fabae have been identified and characterized chemically and biologically. Their use in resistance screenings are being tested and will be critically discussed.

Despite their importance for the agriculture and the environment, the production of food legumes is decreasing in most of the Mediterranean farming systems. A major cause for this is the low and irregular yield as a consequence of biotic and abiotic stresses. Necrotrophic fungi, including essentially Ascochyta and Botrytis species, are among the main biotic constraints. Both fungal genus are well known phytotoxins producers. These toxins, belonging to different classes of natural compounds, are frequently involved in the development of disease symptoms. In this communication the chemical and biological characterization of the necrotrophic effectors produced by Didymella pinodes and Botrytis fabae pathogens of pea and faba bean respectively, will be reported. Furthermore, the studies aimed to identify novel resistance sources in the respective hosts in sensitivity assays will be discussed, too.

The employment of resistant varieties is one of the best options to control diseases in legumes, both in ecological and economical terms. Nevertheless, one of the problems associated to this practice is the appearance of pathogen strains that are able to overcome the plant resistance. This calls for an efficient and wise management of resistance genes in which diversification is always key. We have focused on the use of varietal mixtures to reduce the impact of diseases in two important legume crops: pea and faba bean. Two field experiments were carried out for each crop, the assessed diseases being powdery mildew in pea and rust in faba bean. In both cases, a resistant monogenic variety was mixed with a susceptible one. Five treatments were tested, corresponding to growing proportions of the resistant variety: 0%, 25%, 50%, 75% and 100% (rows of the resistant variety were alternated with varying numbers of rows of the susceptible one depending on the desired proportion). Disease severity was recorded on the susceptible variety in each trial. Results in both experiments show a significant negative correlation between disease severity on the susceptible variety and the proportion of the resistant one. Severity reduction is important when the resistant variety is grown every other row (50% proportion), reaching highest levels with 75% proportion. The dilution effect of inoculum due to the distance between susceptible plants is probably behind these results.

In the course of 2013-2015 abundances of pea aphid (A. pisum) and their natural enemies found on field pea plants, grown either as a monoculture or intercropped with spring cereals and some other legumes, were compared. Two types of trials were used: small plot trials and large plot trials. Pea aphid colonies in field peas in tercropped with cereals developed differently than in pea monocrops. However, the small plot trials showed different results to the large plot trials. In the small plot trials on intercropped plots pea aphid numbers were higher during the first part of crop colonisation, but the decline in aphid populations also happened earlier. In the large plot trials pea aphid abundances were significantly lower in field pea –barley intercrops compared to monocrops during the whole duration of crop infestation. Pea aphid colonies encountered syrphid larvae attacks more frequently in intercrops than in monocrops.

Drought is a recurrent challenge for agriculture around the world, compromising yields and even the survival of crops. Developing strategies to confront the lack of water is a key issue for modern agriculture, moreover in the context of a changing climate. Breeding plays a majar role in this situation, with the introduction of varieties adapted to more dry ecosystems. The identification of genotypes showing tolerance to drought is, then, of great interest. The aim of our work was the identification of genotypes of faba bean that might be employed in breeding for drought. We have tested the response to drought of genotypes previously selected for their performance under biotic stress, mainly diseases. A preliminary trial under controlled conditions permitted to define a visual scale for drought symptoms in faba bean, and to establish the experimental conditions for an optimal discrimination of responses. In a second experiment, a collection of 36 genotypes was assessed. Symptoms were scored for three weeks after the interruption of watering; relative water content of soil was also measured. Results have permitted the identification of a subset of genotypes presenting promising responses. The evaluation of physiological parameters as well as of enzymatic activities in the selected genotypes will be part of future work.

Agriculture is facing the most important challenge in its history. The exponential population growth drives the necessity to improve both crop yield and quality to feed the growing world-wide population. While the mid-XX century Green Revolution based on world-wide cultivation of a few elite cultivars and abuse of chemical to sustain growth and control diseases allowed to improved yield, it also led to a dramatic situation of losses of crop diversity and resilience and heavy pollution of soil and water resources. Thus modern agriculture should also contribute to preserve the environment. One way to achieve both goals is the re-introduction of legume in our growing systems that are an important source of protein and present several benefits for the environments.

Food legumes are annual and multifunctional crops with extraordinary historical importance for the agriculture and the environment of the Mediterranean basin. They are protein-rich and integral part of the Mediterranean diet. Besides, they are used for animal feed and fodder. Grown in rotation with cereals, they improve significantly soil fertility and minimise the use of inorganic nitrogen fetiilizers, contributing to a sustainable and environmentally friendly agriculture in the region. Despite their impotiance, the production of food Iegumes is decreasing in most of the Mediterranean farming systems. A major cause for this is the low and irregular yield as a consequence of biotic and abiotic stresses. The major biotic stress is represented by phytopathogenic fungi belonging to species well known as phytotoxin producers. In this communication we will illustrate the chemical and biological characterization of the phytotoxins produced by Botrytis fabae, the causal agent of chocolate spot of faba bean, and Didymella pinodes, and D. lentis the causal agents of Ascochyta blights of pea and lentil, respectively. For some phytotoxins. the relation between absolute stereochemistry and phytotoxicity will be reported, too.

Medicago truncatula may be used as a model plant to study the pathosystem Vicia faba/Botrytis spp. This study aims to investigate the profiling of the transcription factors (TFs) of M. truncatula involved in the interaction with Botrytis cinerea and Botrytis fabae. The response of two genotypes of M. truncatula to the pathogens was first established, defining genotype A17 as partially resistant and genotype Esp162 as susceptible. We found that B. fabae is more aggressive as a pathogen of M. truncatula than B. cinerea. The profiling of the TFs involved in the interaction was subsequently carried out using an available genome guide qPCR-based platform for the quantitative measurement of 1,084 M. truncatula TFs. Microscopic studies showed that the infection process had started 24 h after inoculation. A total of 126 TFs showed significant differences in their expression after inoculation irrespective of the genotype, while 37 TFs were differentially expressed between the resistant and the susceptible genotypes and 70 TFs showed different levels of expression between the genotypes unaltered by infection. This has allowed characterization at the transcriptional regulation level of the differential response of two genotypes of M. truncatula to two very similar pathogens differing in their aggressiveness. These results will be valuable to increase the functional knowledge of the M. truncatula genome and to help in breeding programmes of V. faba for resistance to Botrytis spp.

An aggressive isolate of Ascochyta lentis obtained from lentil (Lens culinaris L.) produced various metabolites in vitro. The metabolites were isolated from the culture filtrates and characterized by spectroscopic, chemical, and optical methods. A new phytotoxic anthraquinone, named lentisone, was isolated and characterized as (1S,2S,3S)-1,2,3,8-tetrahydroxy-1,2,3,4- tetrahydro-6-methylanthraquinone together with the well-known pachybasin (1-hydroxy-3-methylanthraquinone), tyrosol, and pseurotin A. Lentisone, tyrosol, and pseurotin A were phytotoxic to lentil, with lentisone the most toxic of all. The toxicity of these compounds is light-dependent. Finally, lentisone was also found to be phytotoxic to chickpea, pea, and faba bean, with toxicity in the latter higher than in any other tested legume, including lentil. © 2013 American Chemical Society.

Chocolate spot is an important disease of faba bean (Vicia faba) caused by the necrotrophic fungus Botrytis fabae. The aims of this work were: i) to compare different methods of screening for resistance; ii) to assess the influence of the age of host tissue and temperature on this pathosystem. To this effect, a collection of 42 faba bean accessions was evaluated in mature plant stage in the field in Cordoba (Southern Spain) and in detached leaflet and whole plant tests under controlled conditions. Field results correlated better with those of the whole plant test than with those of the detached leaflet assay. Integration of results from the field and whole plant experiments resulted in the selection of six accessions of interest as sources of resistance. Influence of leaf age on disease development was found to be genotype dependent. Older leaves were more susceptible than younger ones in 23 accessions, while no difference between leaf ages was detected in the remaining accessions. The effects of plant age and temperature were assessed by a whole plant test on seven accessions at two plant ages (4 and 7 weeks) and three temperatures (13, 20, and 25°C). Results showed that the differential genotypic responses to B. fabae were not significantly influenced by either plant age or temperature, although there was a tendency towards lower susceptibility to chocolate spot in faba bean plants as they become older. Further, a partial high-temperature, young-plant resistance was detected. © 2011 KNPV.

The absolute configurations of regiolone and isosclerone, two enantiomeric bioactive naphthalenone pentaketides produced by fungi and plants, have been unambiguously assigned by ab initio computational prediction of their theoretical optical rotatory powers and electronic circular dichroism spectra. Isosclerone is produced by the plant pathogen Botrytis cinerea, whereas regiolone is produced by B. fabae. The phytotoxic activities of the two compounds were tested for comparison on faba bean (host of both pathogens) and vine plants (host of only B. cinerea); the (R) configuration at C-4 was found to be a fundamental structural feature for bioactivity. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The aim of this work was to identify Vicia faba germplasm resistant both to rust and chocolate spot. A collection of 43 accessions of V. faba previously identified as chocolate-spot resistant was evaluated for rust and chocolate spot resistance in Egypt and in Spain. The genotype and genotype × environment (GGE) biplot analyses allowed the selection of 11 accessions resistant to both diseases in those locations. These 11 accessions were evaluated for rust in an additional field trial in Spain, all performing better than the susceptible check. The joint analysis of the 11 accessions in the four field trials where they had been evaluated revealed no significant effects either for genotype, environment or the genotype × environment interaction. They are hence promising sources of resistance, both for their low severities and their stable responses across the studied environments. This collection was also tested under controlled conditions against the Egyptian and the Spanish isolates of rust present in the field trials further underlining the stable performance of these genotypes. Finally, the effect of previous infection with chocolate spot on rust resistance was assessed under controlled conditions and no influence of it was found. © 2011 Elsevier B.V.

A strain of Botrytis fabae isolated from faba bean (Vicia faba L.) plants displaying clear chocolate spot disease symptoms produced phytotoxic metabolites in vitro. The phytotoxins isolated from the culture filtrate organic extract were characterized by spectroscopic and optical methods. A new naphthalenone pentaketide, named botrytone, was isolated and characterized as (4R)-3,4-dihydro-4,5,8-trihydroxy-1(2H)-naphthalenone together with other well-known closely related naphthalenones such as regiolone and cis- and trans-3,4-dihydro-2,4,8-trihydroxynaphthalen-1(2H)-ones. When tested on leaves of the host plant, with the cis- and trans-3,4-dihydro-2,4,8- trihydroxynaphthalen-1(2H)-ones assayed in mixture, regiolone demonstrated the highest level of phytotoxicity together with cis- and trans-3,4-dihydro-2,4,8- trihydroxynaphthalen-1(2H)-ones. Botrytone showed moderate phytotoxic activity at 1 mg/mL and was still phytotoxic at 0.5 mg/mL. © 2011 American Chemical Society.

Successful production of faba bean crops in the presence of a wide range of disease-causing fungi, parasitic weeds, nematodes, insects, mites and other pests depends on the integration of genetic resistance, hygienic management, monitoring of the target organisms and timely application of appropriate chemical and biological treatments. This paper reviews the progress in this area. Arthropod management is still overly reliant on broad-spectrum insecticides for many pests, particularly aphids, but field assessment, tillage, sowing date, plant density and weed control can minimize pest incursions. Crop assessments, bait and pheromone traps and economic thresholds are used to predict and monitor arthropod pest populations, and biological measures (natural enemy conservation and bioinsecticides) and selective chemicals (less harmful to beneficial insects) are also used. Crop hygiene and seed bank demise is critical for management of broomrape, as much of its damage is done before the parasite is visible above ground. Mild herbicide treatments can prevent ripening of broomrape seeds with minimal damage to the faba bean crop. The main diseases caused by fungi, namely rust, ascochyta blight, chocolate spot and downy mildew, all spread rapidly when weather conditions are appropriate. Since these weather conditions are well characterized for each disease, it is possible to intervene strategically by treating with fungicide at times of high risk. Good sources of resistance are available to the key diseases, although few current cultivars are resistant to more than one disease. Root-lesion, stem and root-knot nematodes can cause severe yield losses but several cultivars and breeding lines of faba bean have good resistance to root-lesion nematodes and at least one has resistance to stem nematode and one to root-knot nematode. These groups of nematode species have broad host spectra so attention to rotations is particularly important. Chemical control of nematodes is difficult an

Faba bean is a major grain legume widely cultivated in many countries for food and feed purposes. A number of aerial fungi, together with soil-borne pathogens associated with foot and root rot complexes, nematodes, parasitic weeds and viruses may cause severe diseases in faba bean crops. The use of genetic resistance is the most economical and environmentally friendly control method. However, to date no efficient sources of resistance have been described to some diseases, or it is scarce and of complex nature, making necessary the implementation of other control measures. Phenotypic expression of resistance is usually poorly described. As a consequence of this, and of the poorly developed genomic resources available, the genetic basis of resistances is, in most cases, largely unknown. Effectiveness of MAS might soon increase with the adoption of new improvements in marker technology together with the integration of comparative mapping and functional genomics. In this paper we will review and critically discuss current and future strategies on breeding faba bean for disease resistance. © 2009 Elsevier B.V. All rights reserved.