Root-to-Shoot Hormonal Communication in Contrasting Rootstocks Suggests an Important Role for the Ethylene Precursor Aminocyclopropane-1-carboxylic Acid in Mediating Plant Growth under Low-Potassium Nutrition in Tomato

Selection and breeding of rootstocks that can tolerate low K supply may increase crop productivity in low fertility soils and reduce fertilizer application. However, the underlying physiological traits are still largely unknown. In this study, 16 contrasting recombinant inbred lines (RILs) derived from a cross between domestic and wild tomato species (Solanum lycopersicum × Solanum pimpinellifolium) have been used to analyse traits related to the rootstock-mediated induction of low (L, low shoot fresh weight) or high (H, high shoot fresh weight) vigor to a commercial F1 hybrid grown under control (6 mM, c) and low-K (1 mM, k). Based on hormonal and ionomic composition in the root xylem sap and the leaf nutritional status after long-term (7 weeks) exposure low-K supply, a model can be proposed to explain the rootstocks effects on shoot performance with the ethylene precursor aminocyclopropane-1-carboxylic acid (ACC) playing a pivotal negative role. The concentration of this hormone was higher in the low-vigor Lc and Lk rootstocks under both conditions, increased in the sensitive HcLk plants under low-K while it was reduced in the high-vigor Hk ones. Low ACC levels would promote the transport of K vs. Na in the vigorous Hk grafted plants. Along with K, Ca, and S, micronutrient uptake and transport were also activated in the tolerant Hk combinations under low-K. Additionally, an interconversion of trans-zeatin into trans-zeatin riboside would contribute to decrease ACC in the tolerant LcHk plants. The high vigor induced by the Hk plants can also be explained by an interaction of ACC with other hormones (cytokinins and salicylic, abscisic and jasmonic acids). Therefore, Hk rootstocks convert an elite tomato F1 cultivar into a (micro) nutrient-efficient phenotype, improving growth under reduced K fertilization.This research has received funding from the Spanish MINECO-FEDER (project AGL2014-59728-R) and from the European Union's Seventh Framework Programme for research, technological development and demonstration under grant agreement no 289365 (project ROOTOPOWER).USD 2,116.5 APC fee funded by the EC FP7 Post-Grant Open Access PilotPeer reviewe

Development of sustainable land management policies and practices in five selected countries from 1960 to 2010.

ABSTRACT Since the 1930s there has been worldwide concern about the effects of land degradation. After the problems experienced in the Dust Bowl in the USA, much attention was paid to soil and water conservation in both developed and developing countries. Initially Governments have stimulated the establishment of physical control measures, such as terraces and check dams, and reforestation. This was achieved through top-down regulations, and Forestry Departments were often in charge of the implementation. Subsequently the measures were implemented through more specialised agencies, and later with incentives, such as food aid. In some cases farmers were mobilised to work together on the establishment of the measures. Because of the low success rate of this top-down approach with line interventions, it was realised that a more participatory approach had to be followed. And the emphasis then shifted to area interventions such as cover crops, mulching and composting. In some countries voluntary ways of collaboration between farmers were developed. More recently Conservation Agriculture has been promoted, focusing on less soil disturbance, continuous land cover and crop rotations. This paper analyses whether and to what extent countries have followed such general trends in their soil and water conservation policies, since the 1990s often referred to as sustainable land management, or whether countries have also followed their own specific strategies. A historical (1960-2010) and comparative analysis of the development of these sustainable land management policies and practices is made in five selected countries (Indonesia, Ethiopia, Tunisia, Spain and Bolivia). Keywords: soil and water conservation, sustainable land management, policies, approaches, practice

Randomized, controlled clinical trial of the DIALIVE liver dialysis device versus standard of care in patients with acute-on- chronic liver failure

Background & Aims Acute-on-chronic liver failure (ACLF) is characterized by severe systemic inflammation, multi-organ failure and high mortality rates. Its treatment is an urgent unmet need. DIALIVE is a novel liver dialysis device that aims to exchange dysfunctional albumin and remove damage- and pathogen-associated molecular patterns. This first-in-man randomized-controlled trial was performed with the primary aim of assessing the safety of DIALIVE in patients with ACLF, with secondary aims of evaluating its clinical effects, device performance and effect on pathophysiologically relevant biomarkers. Methods Thirty-two patients with alcohol-related ACLF were included. Patients were treated with DIALIVE for up to 5 days and end points were assessed at Day 10. Safety was assessed in all patients (n = 32). The secondary aims were assessed in a pre-specified subgroup that had at least three treatment sessions with DIALIVE (n = 30). Results There were no significant differences in 28-day mortality or occurrence of serious adverse events between the groups. Significant reduction in the severity of endotoxemia and improvement in albumin function was observed in the DIALIVE group, which translated into a significant reduction in the CLIF-C (Chronic Liver Failure consortium) organ failure (p = 0.018) and CLIF-C ACLF scores (p = 0.042) at Day 10. Time to resolution of ACLF was significantly faster in DIALIVE group (p = 0.036). Biomarkers of systemic inflammation such as IL-8 (p = 0.006), cell death [cytokeratin-18: M30 (p = 0.005) and M65 (p = 0.029)], endothelial function [asymmetric dimethylarginine (p = 0.002)] and, ligands for Toll-like receptor 4 (p = 0.030) and inflammasome (p = 0.002) improved significantly in the DIALIVE group. Conclusions These data indicate that DIALIVE appears to be safe and impacts positively on prognostic scores and pathophysiologically relevant biomarkers in patients with ACLF. Larger, adequately powered studies are warranted to further confirm its safety and efficacy. Impact and implications This is the first-in-man clinical trial which tested DIALIVE, a novel liver dialysis device for the treatment of cirrhosis and acute-on-chronic liver failure, a condition associated with severe inflammation, organ failures and a high risk of death. The study met the primary endpoint, confirming the safety of the DIALIVE system. Additionally, DIALIVE reduced inflammation and improved clinical parameters. However, it did not reduce mortality in this small study and further larger clinical trials are required to re-confirm its safety and to evaluate efficacy. Clinical trial number NCT03065699

A comparative study on variability and phylogeny of Triticum species - 2. Interspecific relationships

Interspecific relationship studies between A, S and D genome diploid species, and between AAGG and AABB allotetraploid species of the genus Triticum were conducted using isoenzymatic characters located in dry mature seeds. Data was analyzed by the factorial analysis of correspondences, and dendograms were obtained by two different genetic distances. The discussion of results was based on the limitations of the study, intraspecific variability differences, isoperoxidase frequency differences and chromosomal location of peroxidases in T. aestivum cv. 'Chinese Spring'. The closest relationship was found between 'dicoccoides' and 'carthlicum'. Relationships found between T. turgidum L.;T. timopheevvi Zhuk.;both allotetraploid species and 'boeoticum'; this species and speltoides; tauschi and searsii, and the last two species with 'bicorne', are discussed at the phylogenetic level. © 1986 Springer-Verlag

A comparative study on variability and phylogeny of Triticum species - 1. Intraspecific variability

Intraspecific variability of A, S and D genome diploid species and AAGG and AABB allotetraploid species of the genus Triticum was examined in a comparative study using isoenzymatic characters (peroxidases of embryo plus scutellum, and endosperm; and alkaline phosphatases) of dry mature seeds. The methodology followed was based on the definition of variables from characters and three functions related with total intraspecific, intrapopulational and interpopulational variabilities. The diploid species with the greatest intraspecific variability were speltoides and longissimum, and among the allotetraploid species, timopheevii. Concerning all variables, interpopulational variability was found to be greater than intrapopulational in urartu, monococcum, timopheevii, dicoccoides and sharonensis. Intraspecific variability differences found among species are discussed with reference to Nevo (1978) and a hypothesis concerning intraspecific variability differences between allotetraploids is suggested. The final objective of the present paper is to provide information on intraspecific variability differences among species for future use in discussing the interspecific relationships. © 1986 Springer-Verlag

Comparative microsatellite linkage analysis and genetic structure of two populations of F6 lines derived from Lycopersicon pimpinellifolium and L. cheesmanii

International audienceA population of recombinant inbred lines (RILs) has several advantages over its F 2 population counterpart with respect to quantitative trait loci (QTLs) and genomic studies. The objective of the investigation reported here was the comparative characterization by simple sequence repeat (SSR) and sequence characterized amplified region (SCAR) markers of two populations of F 6 lines derived from Lycopersicon pimpinellifolium (P population, consisting of 142 lines) and L. cheesmanii (C population, consisting of 115 lines) and sharing the female parent, L. esculentum var. cerasiforme. Almost the same percentage of polymorphic markers was found for each population although a different set of markers was involved. The proportion of SSR primer pairs (93 in total) that resulted in poly-morphism for the main band was larger (55-56%) than for SCAR ones (13-16%). The C population showed the largest proportion of markers with zygotic and gametic segregation distortion, which is in agreement with the larger genetic distance reported between L. esculentum and L. cheesmanii than with the former and L. pimpi-nellifolium. Zygotic distortion corresponded primarily to an excess of heterozygotes in both populations, suggesting that the increment of homozygosity was the main factor limiting viability/self-fertility of the lines. Despite both populations sharing the female parent, P alleles were slightly favored in the P population while E alleles were the most frequently fixed in the C population. A linkage map for each population was obtained, with the average distances between consecutive markers being 3.8 cM or 3.4 cM depending on the population. Discrepancy between the maps for the location of only four markers on chromosomes 3, 6 and 10 was observed. Two possible causes of this discrepancy were investigated and can not be discarded: (1) the presence of duplicated markers and (2) segregation distortion caused by the selective advantage of gametes carrying one of the two alleles. This marker characterization of both populations will continue and will enable the comparative QTLs and candidate gene analysis of complex traits towards a more efficient utilization of genetic resources and breeding strategies