Flowering time is a vulnerable stage of plant development and is therefore a significant determinant of adaptation and grain yield in faba bean (Vicia faba L.). It is largely controlled by genotype, environmental factors of temperature and photoperiod, and genotype-by-environment interactions. The aim of this study was to evaluate variation in flowering time and the responses of flowering time to ambient temperature and photoperiod in Australian faba bean. Time of sowing experiments were carried out to assess variation among lines for flowering time (measured in days to flowering, thermal time to flowering and node of first flower) and to determine plant sensitivities to ambient temperature and photoperiod by regression analysis in the field, while four controlled environment experiments of differing temperature and photoperiod were undertaken to further analyse the variation in responses. Results showed significant variation in responses to both ambient temperature and photoperiod. Photoperiod was the main factor influencing variation in flowering time, with lines grouped as sensitive, intermediate or insensitive. The responses to ambient temperature were more complex. Most lines fit the traditional linear model, but with possible variation in optimal temperature and/or vernalisation response, while some lines showed temperature insensitivity.

Grain legumes in cropping systems result in agronomic and environmental benefits. Nevertheless, their areas in Europe have strongly decreased over the past decades. Our aim was to design locally adapted innovative cropping systems including grain legumes for three European local pedoclimatic contexts, to assess their sustainability, and to discuss their feasibility with stakeholders. The methodology included an initial diagnosis of the most frequent cropping systems and local improvement targets in each local context (e.g. improve legume profitability, limit diseases of legumes, reduce intensive use of chemical inputs in cropping systems), the design of innovative legume-based cropping systems during a common workshop, focusing on three aims ((i) decrease pesticide use, (ii) reduce mineral N fertiliser dependency, and (iii) increase yield stability of grain legume crops and other crops of the crop sequence), and their multicriteria sustainability assessment. Stakeholders meetings were organised in each local context to discuss the feasibility of implementing the innovative cropping systems in farmers’ fields (technical implementation of cropping systems and possibility of development of legume sectors). Four to five cropping systems were designed in each local context, with crop sequences longer than references. They included at least two grain legumes (pea, faba bean, chickpea, lentil or lupine), as sole crops or intercropped with cereals. Overall sustainability was similar or improved in 71% of the legume-based cropping systems compared with their corresponding references. Among the designed cropping systems, stakeholders identified feasible ones considering both technical issues and development of legume sectors. The results indicate that reintegrating more grain legumes in the three European local contexts tested will contribute to more sustainable farming systems.

Mediterranean environments are of most interest to study pea adaptability to terminal drought conditions especially in the current context of global climate change. In our work we have tested nine pea cultivars in five South European and North African locations, characterised by different agro climatic conditions within the Mediterranean climate. Data were processed through the additive main effects and multiplicative interaction analysis. Grain yield, aboveground biomass and flowering date were assessed within each mega-environment with parametric and non-parametric methods, establishing ranks for the genotypes within each condition attending to their stability parameters and mean values. The field analysis revealed HR1 as a wide-adapted genotype, whereas others such as Desso showed the best adaptation in South Mediterranean areas. Our results also highlighted the potential interest of these genotypes and others (i.e. Messire and ZP108) in breeding programs and further studies on drought tolerance.

The aim of this work was to determine the variance components and genetic and environmental stability of 12 cowpea genotypes at three locations (South-east of Spain: Cartagena, South and North of Portugal: Elvas and Vila Real, respectively) in the Iberian Peninsula in two consecutive years (2015 and 2016). The genotype, the environment and the genotype × environment interaction significantly influenced all the morphological and agronomical parameters evaluated. For both years, the highest yields were observed at Elvas, whereas Cartagena and Vila real were the most suitable places to obtain crop precocity. Cartagena was the place where the filling of the seed was the fastest, probably due to the higher temperatures and radiation. The thermal time model (effective degree-days) could be used to predict the period of cowpea development, therefore predict flowering and pod maturity date. Correlation analysis showed that days to flowering, days to maturity and the seed yield vs protein content exhibited negative correlations. The highest heritability was found for plant height and pod length at Cartagena and for 100-seed weight at Elvas and Vila Real. In conclusion, the variations that exist in the studied accessions could give rise to a breeding program to develop cowpea cultivars with interesting agronomic traits.

Legume-based annual forages could be pivotal for the sustainable intensification of forage production in drought-prone Mediterranean cereal-livestock systems. This study aimed to optimise the composition of these crops for three climatically contrasting areas. Four legumes (field pea of semi-dwarf and tall type; Narbon vetch; common vetch) and two cereals (oat; triticale) were grown in three autumn-sown sites (Sassari, Italy; Sétif, Algeria; Marchouch, Morocco) for 2 years as pure stands and legume-cereal binary and four-component mixtures. We assessed dry matter yield, weed content and farmers’ acceptability of the crops, and legume content and Land Equivalent Ratio of the mixtures. Legumes’ competitive disadvantage ranged from very high in Sétif to nearly nil in Sassari. Pea- and common vetch-based mixtures out-performed Narbon vetch-based ones in terms of yield, legume content and farmers’ acceptability. The tall pea, featuring greatest competitive ability against cereals, maximised the yield and legume content of legume-cereal crops. Vetch-cereal mixtures exhibited lower weed content than the average of the components’ pure stands. Oat monoculture was top-yielding but modestly appreciated by farmers. Pea provided the only legume monoculture combining good yielding ability and high farmers’ appreciation. Greater species diversity as provided by complex mixtures did not display any production advantage over binary mixtures.

Grass–legume mixtures are key crops to improve agricultural sustainability. Despite their significant use in mixture, lucerne (Medicago sativa L.) varieties are mostly tested and bred for monocultures. This study was performed to evaluate whether the ranking of lucerne genotypes for biomass components and quality was similar in monoculture and mixture, and whether traits recorded on isolated plants could help to predict performance in monoculture and mixture. For 46 genotypes planted in the three competition conditions, plant biomass, shoot height, shoot number and protein content were recorded. In addition, maximum leaf size, internode length, stem diameter, growth habit, specific leaf area and leaf dry-matter content were measured on isolated plants. A general positive correlation was observed between the performance of genotypes in monoculture and in mixture. However, significant changes in genotype ranking indicated that the species of its neighbours could modify the relative performance of a genotype. The traits that minimised competition intensity also changed according to the neighbour species. In mixture, competition intensity was highest for plants with long internodes, a high shoot number and a non-erect growth habit. In monoculture, plants with long internodes and larges leaves suffered less from competition. The agronomic performance of lucerne varieties differing in their architecture should be compared in monoculture and mixture to finally identify the traits to be phenotyped to improve lucerne variety performance in both cultivation modes.

Selection of grazing-tolerant lucerne (Medicago sativa L.) for mild-winter environments is challenged by marked cold-season dormancy and prostrate habit often observed in tolerant material. This study aimed to assess the amount of genetic variation and genetically based trade-offs for key traits in four biparental populations, and their implications for selection. Some 432 cloned F₁ progenies from four crosses between contrasting genotypes (erect, not very dormant, non-grazing tolerant v. prostrate, dormant, tolerant) were evaluated for dry matter (DM) yield and final plant persistence under continuous, intense sheep grazing for 3 years, along with a set of morpho-physiological traits. Both DM yield and persistence displayed negative genetic correlation with erect plant habit (r_g –0.31 to –0.87, depending on the cross), with persistence inversely related also to cold-season growth (r_g –0.33 to –0.73). Correlations of performance traits with DM yield before grazing management, plant diameter and leaflet area were inconsistent or nil. DM yield during grazing management and persistence exhibited large genetic variation (CV_g 33.3–57.8%), and within-cross variance largely exceeded between-cross variance. Morpho-physiological traits had lower genetic variation and even greater relative within-cross variance than yield and persistence. Selection for grazing-tolerant germplasm could exploit large genetic variation, but it requires extensive within-cross genotype evaluation to produce material with little dormancy and relatively erect growth habit.

Subterranean clover (Trifolium subterraneum L.) is widely grown for its forage and ability to fix atmospheric nitrogen. Development of new varieties is constrained by the slow turnover time of generations, with only one generation per year possible under field conditions. We present an in vitro-assisted single-seed descent (IVASSD) technique, which enabled turnover of 2.7–6.1 generations per year across a diverse range of 27 T. subterraneum cultivars encompassing subspecies subterraneum, yanninicum and brachycalycinum. The IVASSD protocol accelerated the generation cycle in two ways: (i) time to floral initiation was minimised by growth under controlled temperature and extended photoperiod; and (ii) the seed-filling period was truncated and embryo and seed-coat dormancy avoided by the in vitro germination of immature seed on B5 medium plus L6KK overlay (0.525 mg gibberellic acid and 1.5 mg indole-butyric acid L^–1). For the first time, an IVASSD system was validated on a full-scale breeding population with the production of 175 F₇ recombinant inbred lines from an F₄ population in less than one year. All F₇ plants obtained were morphologically normal and fertile.

Appearance and size of chickpea (Cicer arietinum L.) seeds are key factors for the market in the Mediterranean Basin driven by consumer preferences. Hence, kabuli large seeds are sold on the market at higher price than the desi seeds. In this crop, Ascochyta blight (caused by Ascochyta rabiei (Pass.) Lab.) is a serious disease causing major losses in yield. Thus, developing large-seeded kabuli cultivars resistant to blight would be of great importance to farmers. In this study, the use of transgressive inheritance to select new allelic combinations for seed size was applied to develop new chickpea materials with large seeds and resistance to blight. Crosses between five different advanced lines of kabuli chickpea genotypes with medium–large seed size and resistant to blight were performed. As a results of the selections carried out during 10 successive years, 11 F_5:9 lines resistant to blight and with large seed size were selected to be released as future varieties. The markers SCY17₅₉₀ and CaETR were employed to confirm blight resistance of the material developed.

Breeding and cultivar improvement are important for increasing crop yields. In this study, 1472 soybean cultivars released in the last 60 years and 683 landrace cultivars from three regions of China (North spring soybean region, Yellow-Huai-Hai summer soybean region, and South soybean region) were collated to examine changes in agronomic characters and plant density that might be associated with yield improvement. The yield and 100-seed weight of the soybean cultivars increased significantly over time in all three regions. Planting density decreased significantly in the Yellow-Huai-Hai summer and South soybean regions but did not significantly change in the North spring soybean region. The increased soybean yields were mainly due to increased 100-seed weight and seed number per plant. Seed protein content has not significantly changed in 60 years, but oil content has increased in all three regions. The North spring soybean region had the highest oil content, whereas the South soybean region had the highest protein content. Future increases in soybean yield in China may occur by improving seed number per plant without reducing 100-seed weight. The North spring region should focus on breeding soybean with high oil content, and the Yellow-Huai-Hai summer and South regions should focus on high protein and low oil contents.

Thermal stress during reproductive development and grain-filling phases is a serious threat to the quality and productivity of grain legumes. The optimum temperature range for grain legume crops is 10−36°C, above which severe losses in grain yield can occur. Various climatic models have simulated that the temperature near the earth’s surface will increase (by up to 4°C) by the end of this century, which will intensify the chances of heat stress in crop plants. The magnitude of damage or injury posed by a high-temperature stress mainly depends on the defence response of the crop and the specific growth stage of the crop at the time of exposure to the high temperature. Heat stress affects grain development in grain legumes because it disintegrates the tapetum layer, which reduces nutrient supply to microspores leading to premature anther dehiscence; hampers the synthesis and distribution of carbohydrates to grain, curtailing the grain-filling duration leading to low grain weight; induces poor pod development and fractured embryos; all of which ultimately reduce grain yield. The most prominent effects of heat stress include a substantial reduction in net photosynthetic rate, disintegration of photosynthetic apparatus and increased leaf senescence. To curb the catastrophic effect of heat stress, it is important to improve heat tolerance in grain legumes through improved breeding and genetic engineering tools and crop management strategies. In this review, we discuss the impact of heat stress on leaf senescence, photosynthetic machinery, assimilate translocation, water relations, grain quality and development processes. Furthermore, innovative breeding, genetic, molecular and management strategies are discussed to improve the tolerance against heat stress in grain legumes.

Powdery mildew (PM) is a devastating disease of many legume species, including common bean. In this work, we assessed the responses of 108 dry and snap bean accessions to PM, and characterised the genetic control of the resistance in three bean genotypes. Resistance tests under controlled conditions led to the identification of 11 dry bean accessions with total resistance. However, no snap bean accessions showed total resistance, although two cultivars showed mixed phenotypes including seedlings with total resistance. The inheritance of resistance was analysed in three F_2:3 populations involving the resistant bean genotypes BelNeb, G19833 and BGE003161. In the three populations, the segregation for PM resistance fit the expected ratio for one dominant gene. The resistance loci were mapped to the beginning of the linkage group Pv04. The physical positions of the flanking markers indicated that the three resistance genes were located between the physical positions 0 and 1.09 Mb. This work provides new PM-resistance sources and markers linked to resistance genes, which will be very useful in common bean breeding programs focussed on protecting bean crops against this disease.

A germplasm collection of 484 accessions of Vicia faba was screened for resistance to rust (Uromyces viciae-fabae) under field conditions. Accessions varied in the levels of rust infection, although no complete resistance was identified. Stability of resistance of the 39 most-resistant accessions was tested in a multi-location experiment in Austria, Egypt, Tunisia, United Kingdom and Spain over three additional field seasons. Genotype × environment interaction accounted for 43% of the sum of squares of the multi-environment evaluation, revealing instability of the phenotypic expression across environments. This might hamper the efficiency of selection suggesting the need for selection in different environments. Three possible mega-environments were discerned in the studied area, Mediterranean (Spain, Tunisia and Egypt), Oceanic (UK) and Continental (Austria). Córdoba (Spain) and Kafr El-Sheik (Egypt) showed as ideal environments for rust resistance screenings within Mediterranean environment. Several accessions (300, 303, 311, 313, 720, 1196 and 1271) were grouped as moderately to highly resistant in the three defined mega-environments. These accessions showed clear differences both in terms of reduced disease severity and high stability, which make them good candidates for international faba bean breeding programmes. Concerning each mega-environment, accessions 300 and 311 were the most resistant and stable ones across the Mediterranean one, followed by accessions 720, 1022, 1272, 1320 and BPL261. On the contrary other accessions (313, 452, 481 and 1196) were the most resistant in Oceanic and Continental environments. However, 452 and 481 were susceptible in the Mediterranean mega-environment. This contrasting performance across the environments was also supported by contradictory performance of the checks BPL261 and Baraca in Oceanic and Continental environments, suggesting differential virulence in rust populations, which deserves further attention.

Fusarium wilt (caused by Fusarium oxysporum f. sp. lentis) is the most crucial limiting variable for decreasing yield levels of lentils (Lens culinaris Medik.) around the world. A set of 20 diverse lentil genotypes comprising breeding lines and released varieties was evaluated, along with susceptible controls, for resistance to fusarium wilt through natural incidence for two continuous years (2010–11 and 2011–12) in six diverse lentil-growing environments in India. Analysis of variance showed that the effect of genotype (G) and environment (E) for disease incidence was highly significant. Among the three sources of variation, the biggest contribution in disease occurrence was accounted for by environment (54.68%), followed by G × E interaction (17.32%). The high G × E variation necessitated assessment of the genotypes at different locations (environments). GGE biplot analysis of the studied genotypes revealed that genotype PL 101 and released cultivar L 4076 had low levels of disease incidence. The sources of resistance to fusarium wilt have great potential for use in lentil-breeding programs. Another biplot of relationships among environments demonstrated that, among the test locations, Sehore and Faizabad, were the most effective for differentiation of genotypes. On the basis of discriminating ability and representativeness, the Sehore location appeared an ideal testing site for natural incidence of F. oxysporum f. sp. lentis.

Seed and flour characteristics of 79 chickpea (Cicer arietinum L.) accessions from a representative collection of the germplasm used by European breeders were evaluated. The accessions were grouped according to desi or kabuli types and by different seed traits (size, shape, colour, surface). The variation in nutritional composition was assessed by principal component analysis (PCA) of data from 13 quality parameters. The first PCA component discriminated the accessions by basic composition (protein, fibre, fat) plus δ-tocopherol, and the second by carotenoid composition (zeaxanthin). Whereas desi types showed higher protein and fibre, kabuli accessions exhibited higher fat contents. The majority of accessions analysed showed very low (<1%) resistant starch content. Higher carotenoid concentration was obtained in desi-type accessions and it was related to specific seed traits: small seed size, angular shape and black colour. Besides discrimination between desi and kabuli groups, the detected associations of classes of shape, size and colour seed traits can be explored in chickpea-quality breeding programs. Several accessions showed higher concentrations of α-tocopherol (>200 μg g^–1). LEGCA728, with green colouring in the seed coat and cotyledons, showed exceptional lutein concentration (28.32 μg g^–1). We conclude that the chickpea germplasm in use by European breeders presents high potential for improvement of nutritional and health-benefit components not yet routinely implemented in the breeding of this important pulse crop.

Chickpea (Cicer arietinum L.) is an essential grain for human consumption owing to its high protein content, nutritional quality and energy-efficient production. The aim of this study was to compare the protein extracts of 24 chickpea genotypes by biochemically characterising the storage proteins. The storage protein content was characterised by protein separation with polyacrylamide gel electrophoresis and visualisation of the banding patterns, which revealed considerable genetic variability within and between genotypes in this chickpea collection. High performance liquid chromatography showed that all genotypes had balanced amino acid content and some were rich in seven amino acids. Two chickpea genotypes, Flip97-171C and Elite, representative of the kabuli and desi types, respectively, were chosen for total proteome analysis. Two-dimensional electrophoresis and subsequent mass spectrometry were used to identify 454 protein spots from the Flip97-171C and Elite proteomes. By using Mascot Server software, 37% of the spots were identified as 47 different proteins involved in a large range of metabolic functions. Most proteins from both proteomes were assigned to nutritional storage activity. Chickpea proteome analysis is essential in reaffirming the quality of this grain protein for human nutrition, and will be important in future nutriproteomics and plant-breeding studies.

Cowpea (Vigna unguiculata (L.) Walp.), a plant broadly cultivated for human consumption and animal feed, is among the most nutritious grain legumes. Most of the areas where cowpea is grown are drought-prone, and there is a need to address this issue, with water scarcity becoming a major concern in agriculture. Cowpea is known to form mutualistic associations with nitrogen-fixing (NF) bacteria and arbuscular mycorrhizal (AM) fungi. These beneficial soil microorganisms have the capacity to benefit plants by reducing the effects of environmental stresses, including drought. Our aim was to study the effect of inoculation with Bradyrhizobium elkanii and Rhizophagus irregularis on the growth and grain yield of cowpea under water-deficit conditions. Under moderate water deficit, grain yield was increased by 63%, 55% and 84% in plants inoculated with B. elkanii, R. irregularis and B. elkanii   R. irregularis, respectively. Under severe water deficit, inoculation with B. elkanii and B. elkanii   R. irregularis resulted in grain-yield enhancement of 45% and 42%, respectively. The use of cowpea inoculated with NF bacteria and AM fungi has great potential for sustainable agricultural production under drought conditions.

Winter cover crops may provide different environmental benefits in agricultural systems. The aim of this study was to determine the effect of cover crops used as green manure on the soil nitrogen (N) budget and yield of silage maize (Zea mays L.). A field experiment was conducted between 2011 and 2013 at three locations in Vojvodina Province, Serbia. It compared common vetch (Vicia sativa L.), triticale (× Triticosecale Wittm. ex A. Camus), their mixture grown as cover crops, N fertilisation at two doses (N1 and N2), and an unfertilised fallow as a control. Cover crops were sown in autumn 2011 and 2012 and were ploughed in during May of the year after which silage maize was sown. Results show that the ability of cover crops to provide benefit for a subsequent crop is highly related to weather conditions, mainly precipitation. The two years of the study experienced completely different weather conditions, showing two aspects of how cover crops can affect subsequent crop yield and amount of N left in the soil. In 2012, the N budget was higher in all three cover crops at all locations than N1 and the control because of unfavourable weather conditions for mineralisation of organic matter. However, the cover crops had a negative effect on silage maize yield. In 2013 (an average year), the N budget was significantly higher after cover crops, and was followed by a higher yield of silage maize. Based on the 2-year average, the highest value of apparent N remaining in the soil was recorded in the mixture treatment (288.13 kg N ha^–1); treatments with vetch and triticale had approximately equal values (272.17 and 272.71 kg N ha^–1). The N fertilisation treatments and the control had significantly lower average values of residual N.

Changing agricultural practices from conventional to conservation tillage generally leads to increased weed populations and herbicide use. To gain information about the possible use of lucerne (Medicago sativa L.) cover crop as an alternative and sustainable weed-control strategy for winter wheat (Triticum aestivum L.), an experiment was performed at Thiverval-Grignon, France, from 2008 to 2010. We compared conventional and reduced tillage as well as the presence and absence of living mulch (i.e. lucerne) on weeds and wheat production. Percentage soil coverage and aboveground biomass of wheat, lucerne and weeds were measured at the end of grain filling. Weed communities were analysed in terms of composition and diversity. During both seasons, wheat biomass did not significantly decrease in reduced-till trials compared with conventional ones (7.0 and 7.2 t ha^–1, respectively, in 2008–09; 6.9 and 7.1 t ha^–1 in 2009–10). Regardless of soil management, the percentage soil coverage by wheat significantly decreased when it was intercropped, although wheat biomass was not significantly reduced compared with the sole crop. To minimise cash-crop losses, we studied the competition between wheat, lucerne and weeds, testing various herbicide strategies. Early control of lucerne allowed better balance between weed control and wheat development. In addition, weed communities varied among treatments in terms of abundance and composition, being reduced but more varied in plots associated with lucerne. A functional group analysis showed that grasses benefited from reduced-till conditions, whereas problematic weeds such as annuals with creeping and climbing morphologies were substantially reduced. In addition, annual and perennial broad-leaf species with rosette morphology were also significantly decreased when lucerne was used as living mulch. Wheat production in reduced-till conditions intercropped with lucerne living mulch may be useful for integrated weed management, reducing the need for herbicides.