Abiotic Stress Responses in Legumes: Strategies Used to Cope with Environmental Challenges

Legumes are well recognized for their nutritional and health benefits as well as for their impact in the sustainability of agricultural systems. The threatening scenario imposed by climate change highlights the need for concerted research approaches in order to develop crops that are able to cope with environmental stresses, while increasing yield and quality. During the last decade, some physiological components and molecular players underlying abiotic stress responses of a broad range of legume species have been elucidated. Plant physiology approaches provided general outlines of plant responses, identifying stress tolerance-related traits or elite cultivars. A thorough identification of candidate genes and quantitative trait loci (QTLs) associated with these traits followed. Model legumes like Medicago truncatula, Lotus japonicus, and more recently, Glycine max provided valuable translational approaches for dissecting legume responses to abiotic stresses. The challenge now focuses on the translation of the information gained in model systems in controlled environments to crops grown under field conditions. In this review, we provide a general overview of the recent achievements on the study of abiotic stress responses in a broad range of model, grain and forage legumes species, highlighting the different approaches used. Major accomplishments, as well as limitations or drawbacks are discussed across the different sections. Some perspectives regarding new approaches for screening, breeding or engineering legumes with desirable abiotic stress resistance traits are anticipated. These advances will support the development of legumes better adapted to environmental constraints, tackling current demands on modern agriculture and food production presently exacerbated by global climate changes

Étude du comportement de deux variétés de soja dans le Nord de la France. Influence de la densité

Le comportement de 2 variétés de soja du groupe de maturité 000 a été étudié en 1988 et 1989, en conditions de plein champ dans le Nord de la France. Ces 2 génotypes se différencient par leur croissance indéterminée (Sito) ou semi-déterminée (Fiskeby). L'étude a été réalisée pour des peuplements de 40, 80 et 120 plantes par m2. La floraison et la croissance des fruits débute avant que la croissance de l'appareil végétatif ne soit terminée. Cette période de compétition pour les assimilats est plus longue chez Sito que chez Fiskeby. À 40 et 80 plantes par m 2, la production en graines de Sito est supérieure à celle de Fiskeby. Dans ces conditions, le rendement est relié positivement à la quantité maximale de matière sèche végétative élaborée par le peuplement. Le passage de 40 à 80 plantes par m2 permet d'augmenter le rendement en produisant une plus grande quantité de matière sèche végétative, par unité de surface. À 120 plantes/m2, la variété semi-déterminée Fiskeby a un rendement plus élevé que Sito. À cette densité, ni la matière sèche végétative maximale, ni l'indice de récolte ne différencient les 2 variétés. Les raisons de ce comportement sont donc à rechercher au niveau de la capacité du couvert végétal à produire des assimilats et à les transférer jusqu'aux grains.Soybean behaviour in the north of France. Comparison between semi-determinate and indeterminate types and effects of plant population. The behaviour of 2 soybean varieties of maturity group 000 was studied in the north of France in 1988 and 1989 under field conditions. These 2 genotypes differ in their growth habit: indeterminate (Sito) and semi-determinate (Fiskeby). This experiment was conducted on populations of 40, 80 and 120 plants/m2. Blooming and fruit growth begin before vegetative growth is fully completed (figs 1, 2). This competition period for assimilates is longer for Sito than for Fiskeby. At 40 and 80 plants per m2, Sito grain production is more important than that of Fiskeby (fig 4). Under these conditions, grain yield is positively related to maximum vegetative dry weight (fig 3). The 80 plant/m2 population allows a higher grain yield than the 40 plant/m 2 by producing more vegetative dry weight on the same area basis (fig 3; table III). At 120 plants/m2, the semi-determinate variety Fiskeby shows a higher grain yield than Sito. At this density, maximum vegetative dry weight and harvest index are the same for both genotypes (fig 3, tables III, IV) and cannot explain the yield difference. Reasons for this behaviour have to be investigated at the level of the canopy's capacity for assimilate production and translocation

Influence du froid sur la survie des plantes

National audienc

Analysis of a 5-parent half diallel in dried pea (Pisum sativum L). I. Seed yield heterosis

Values of heterosis for seed yield and related traits have been calculated on F1 hybrids of dried pea (Pisum sativum L), obtained in a 5-parent half diallel cross. Lines used as parents represented a good sample of the genetic variability found in Northern Europe cultivars. The experiment was performed in microplots under competitive conditions (density: 100 pl/m2). Seed yield showed highly significant heterosis: 40% over the mid parent and 20% over the high parent respectively. Both general and specific combining ability were important. This study also concluded that heterosis was mainly expressed on branches. Heterosis for yield components was significant only for the number of pods/plant and the number of sseds/pod on the branches, but not for the number of seeds/pod on the whole plant or for dry weight/seed.Analyse d'un demi-diallèle à 5 parents chez le pois. I. Hétérosis du rendement en grains. Les valeurs d'hétérosis du rendement en grains et de caractères liés au rendement ont été calculées chez des hybrides F1 de pois (Pisum sativum L), obtenus dans un croisement demi-diallèle à 5 parents. Les lignées utilisées comme parents représentaient un bon échantillon de la variabilité génétique des cultivars du Nord de l'Europe. L'expérimentation a été effectuée en micro-parcelles, en conditions de compétition (densité : 100 pl/m2). Le rendement en grains a montré un hétérosis significatif : respectivement 40% par rapport au parent moyen et 20% par rapport au meilleur des 2 parents. Les aptitudes générale et spécifique à la combinaison étaient importantes. Cette étude a souligné le fait que le phénomène d'hétérosis s'exprimait principalement au niveau des ramifications. L'hétérosis pour les composantes du rendement était significatif seulement pour le nombre de gousses par plante et le nombre de graines par gousse sur les ramifications mais ne l'était pas pour le nombre de graines par gousse au niveau de la plante entière ni pour le poids sec du grain

Marker-assisted selection of genetic variants for seed trypsin inhibitor content in peas

International audienceDespite their low contents in seeds, protease inhibitors in pea (Pisum sativum L.) have been shown to be important in negatively affecting the performance of pig or poultry. The quantification of these inhibitors by chemical methods is time-consuming and expensive, prompting the development of simple markers to boost progress in breeding programs. Gene polymorphism linked to variation in seed trypsin inhibitor activity has allowed the definition of primers for polymerase chain reaction (PCR) assays, which can be exploited in breeding programs and offer an efficient and cheap pre-screening procedure

Analysis of a 5-parent half diallel in dried pea (Pisum sativum L). I. Seed yield heterosis

Values of heterosis for seed yield and related traits have been calculated on F1 hybrids of dried pea (Pisum sativum L), obtained in a 5-parent half diallel cross. Lines used as parents represented a good sample of the genetic variability found in Northern Europe cultivars. The experiment was performed in microplots under competitive conditions (density: 100 pl/m2). Seed yield showed highly significant heterosis: 40% over the mid parent and 20% over the high parent respectively. Both general and specific combining ability were important. This study also concluded that heterosis was mainly expressed on branches. Heterosis for yield components was significant only for the number of pods/plant and the number of sseds/pod on the branches, but not for the number of seeds/pod on the whole plant or for dry weight/seed.Analyse d'un demi-diallèle à 5 parents chez le pois. I. Hétérosis du rendement en grains. Les valeurs d'hétérosis du rendement en grains et de caractères liés au rendement ont été calculées chez des hybrides F1 de pois (Pisum sativum L), obtenus dans un croisement demi-diallèle à 5 parents. Les lignées utilisées comme parents représentaient un bon échantillon de la variabilité génétique des cultivars du Nord de l'Europe. L'expérimentation a été effectuée en micro-parcelles, en conditions de compétition (densité : 100 pl/m2). Le rendement en grains a montré un hétérosis significatif : respectivement 40% par rapport au parent moyen et 20% par rapport au meilleur des 2 parents. Les aptitudes générale et spécifique à la combinaison étaient importantes. Cette étude a souligné le fait que le phénomène d'hétérosis s'exprimait principalement au niveau des ramifications. L'hétérosis pour les composantes du rendement était significatif seulement pour le nombre de gousses par plante et le nombre de graines par gousse sur les ramifications mais ne l'était pas pour le nombre de graines par gousse au niveau de la plante entière ni pour le poids sec du grain

Grain yield in winter and spring protein pea cultivars (Pisum sativum L.) with normal and afila leaf types

International audienc

Variation in tolerance to radiant frost at reproductive stages in field pea germplasm

Radiant frost is a major abiotic stress, particularly at the reproductive stage, in field pea (Pisum sativum L.) grown in Mediterranean environments. Here, response to frost was studied for flowering stage (FS) organs (buds, flowers and set pods) and pod development stage (PDS) organs (flat, swollen and mature pods) under controlled conditions, with plants exposed to a minimum temperature of –4.8°C for 4 h. This frost treatment adversely affected seed yield through (i) abortion of buds, flowers and set pods (ii) death of pods and (iii) reduction in seed size. FS organs were more sensitive to frost than PDS organs. Genetic variation was observed among 83 accessions collected from 34 countries worldwide for survival of FS buds, flowers and set pods. In 60 of 83 accessions, no buds, flowers or set pods survived the frost treatment. Five accessions: ATC 104 (origin: United Kingdom), ATC 377 (Estonia), ATC 968 (Italy), ATC 3992 (Kazakhstan) and ATC 4204 (China), showed the highest frost tolerance of FS organs and lowest numbers of abnormal seeds. The frost tolerant accessions identified in this study may be useful as parents for breeding field pea varieties that will be less likely to suffer yield loss due to radiant frost during the reproductive stage.Shaista Shafiq, Diane E. Mather, Maqbool Ahmad and Jeffrey G. Paul