Interspecific hybridization improves the performance of Lotus spp. under saline stress
Abstract Salinity is one of the most frequent limiting conditions in pasture production for grazing livestock. Legumes, such as Lotus spp. with high forage quality and capable of adapting to different environments, improves pasture performance in restrictive areas. In order to determine potential cultivars with better forage traits, the current study assess the response to salt stress of L. tenuis, L. corniculatus and a novel L. tenuis x L. corniculatus accession. For this purpose, chlorophyll fluorescence, biomass production, ion accumulation and anthocyanins and proanthocyanidins levels have been evaluated in control and salt-treated plants PSII activity was affected by salt in L. tenuis,…
The proanthocyanidin content as a tool to differentiate between Lotus tenuis and L. corniculatus individuals
Abstract Lotus tenuis Wald et Kit and Lotus corniculatus L. are conspicuous elements of the agricultural landscape for cattle production. In South America, commercial L. tenuis stocks usually present contaminations with L. corniculatus, what brings about an important economical injure to the forage producers. A way to reduce or avoid loses is to assess the purity degree of L. tenuis seed lots before seeding. Methods so far described for the diagnosis of Lotus species when flowers are not available are lengthy, time consuming, need the implementation of sophisticated laboratories and are relatively expensive. It has been shown that Lotus species accumulate variable proanthocyanidins amounts,…
Defense Responses in Two Ecotypes of Lotus japonicus against Non-Pathogenic Pseudomonas syringae
Lotus japonicus is a model legume broadly used to study many important processes as nitrogen fixing nodule formation and adaptation to salt stress. However, no studies on the defense responses occurring in this species against invading microorganisms have been carried out at the present. Understanding how this model plant protects itself against pathogens will certainly help to develop more tolerant cultivars in economically important Lotus species as well as in other legumes. In order to uncover the most important defense mechanisms activated upon bacterial attack, we explored in this work the main responses occurring in the phenotypically contrasting ecotypes MG-20 and Gifu B-129 of L. ja…
Response to long-term NaHCO3-derived alkalinity in model Lotus japonicus Ecotypes Gifu B-129 and Miyakojima MG-20: transcriptomic profiling and physiological characterization.
The current knowledge regarding transcriptomic changes induced by alkalinity on plants is scarce and limited to studieswhere plants were subjected to the alkaline salt for periods not longer than 48 h, so there is no information availableregarding the regulation of genes involved in the generation of a new homeostatic cellular condition after long-termalkaline stress.Lotus japonicusis a model legume broadly used to study many important physiological processes includingbiotic interactions and biotic and abiotic stresses. In the present study, we characterized phenotipically the response toalkaline stress of the most widely usedL. japonicusecotypes, Gifu B-129 and MG-20, and analyzed global t…
Evaluation of a technical revegetation action performed on foredunes at Devesa de la Albufera, Valencia, Spain
We have evaluated the level of restoration achieved by a technical revegetation action carried out on reconstructed foredunes at the Devesa de la Albufera and compared this level with that achieved by spontaneous succession. Foredunes 1, 3, 6 and 20 y old since revegetated (1, 3, 6 and 20 y, respectively) were considered as spatially separated stages representing a successional trend in the development of the restored plant community. Lower and similar levels of diversity (richness and H´ and Pielou´s indexes) and coverage, respectively, were found on dunes corresponding to the oldest stage of technical revegetation compared with that of the reference site. Diversity and coverage parameters…
Ecological and agronomic importance of the plant genus Lotus. Its application in grassland sustainability and the amelioration of constrained and contaminated soils
The genus Lotus comprises around 100 annual and perennial species with worldwide distribution. The relevance of Lotus japonicus as a model plant has been recently demonstrated in numerous studies. In addition, some of the Lotus species show a great potential for adaptation to a number of abiotic stresses. Therefore, they are relevant components of grassland ecosystems in environmentally constrained areas of several South American countries and Australia, where they are used for livestock production. Also, the fact that the roots of these species form rhizobial and mycorrhizal associations makes the annual L. japonicus a suitable model plant for legumes, particularly in studies directed to r…
Characterization of the Copper Transporters from Lotus spp. and Their Involvement under Flooding Conditions
Forage legumes are an important livestock nutritional resource, which includes essential metals, such as copper. Particularly, the high prevalence of hypocuprosis causes important economic losses to Argentinian cattle agrosystems. Copper deficiency in cattle is partially due to its low content in forage produced by natural grassland, and is exacerbated by flooding conditions. Previous results indicated that incorporation of Lotus spp. into natural grassland increases forage nutritional quality, including higher copper levels. However, the biological processes and molecular mechanisms involved in copper uptake by Lotus spp. remain poorly understood. Here, we identify four genes that encode p…
Plant virus evolution under strong drought conditions results in a transition from parasitism to mutualism
Environmental conditions are an important factor driving pathogens’ evolution. Here, we explore the effects of drought stress in plant virus evolution. We evolved turnip mosaic potyvirus in well-watered and drought conditions in Arabidopsis thaliana accessions that differ in their response to virus infection. Virus adaptation occurred in all accessions independently of watering status. Drought-evolved viruses conferred a significantly higher drought tolerance to infected plants. By contrast, nonsignificant increases in tolerance were observed in plants infected with viruses evolved under standard watering. The magnitude of this effect was dependent on the plant accessions. Differences in to…
Lotus tenuis x L. corniculatus interspecific hybridization as a means to breed bloat-safe pastures and gain insight into the genetic control of proanthocyanidin biosynthesis in legumes
Background: Proanthocyanidins (PAs) are secondary metabolites that strongly affect plant quality traits. The concentration and the structure of these metabolites influence the palatability and nutritional value of forage legumes. Hence, modulating PAs in the leaves of forage legumes is of paramount relevance for forage breeders worldwide. The lack of genetic variation in the leaf PA trait within the most important forage species and the difficulties in engineering this pathway via the ectopic expression of regulatory genes, prompted us to pursue alternative strategies to enhance this trait in forage legumes of agronomic interest. The Lotus genus includes forage species which accumulate PAs …