Harvest index, a parameter conditioning responsiveness of wheat plants to elevated CO2

The expansion of the world’s population requires the development of high production agriculture. For this purpose, it is essential to identify target points conditioning crop responsiveness to predicted [CO2]. The aim of this study was to determine the relevance of ear sink strength in leaf protein and metabolomic profiles and its implications in photosynthetic activity and yield of durum wheat plants exposed to elevated [CO2]. For this purpose, a genotype with high harvest index (HI) (Triticum durum var. Sula) and another with low HI (Triticum durum var. Blanqueta) were exposed to elevated [CO2] (700 µmol mol–1 versus 400 µmol mol–1 CO2) in CO2 greenhouses. The obtained data highlighted that elevated [CO2] only increased plant growth in the genotype with the largest HI; Sula. Gas exchange analyses revealed that although exposure to 700 µmol mol–1 depleted Rubisco content, Sula was capable of increasing the light-saturated rate of CO2 assimilation (Asat) whereas, in Blanqueta, the carbohydrate imbalance induced the down-regulation of Asat. The specific depletion of Rubisco in both genotypes under elevated [CO2], together with the enhancement of other proteins in the Calvin cycle, revealed that there was a redistribution of N from Rubisco towards RuBP regeneration. Moreover, the down-regulation of N, NO3 –, amino acid, and organic acid content, together with the depletion of proteins involved in amino acid synthesis that was detected in Blanqueta grown at 700 µmol mol–1 CO2, revealed that inhibition of N assimilation was involved in the carbohydrate imbalance and consequently with the down-regulation of photosynthesis and growth in these plants

A Microbial-Based Biostimulant Enhances Sweet Pepper Performance by Metabolic Reprogramming of Phytohormone Profile and Secondary Metabolism

Microbial-based biostimulants can improve crop productivity by modulating cell metabolic pathways including hormonal balance. However, little is known about the microbial-mediated molecular changes causing yield increase. The present study elucidates the metabolomic modulation occurring in pepper (Capsicum annuum L.) leaves at the vegetative and reproductive phenological stages, in response to microbial-based biostimulants. The arbuscular mycorrhizal fungi Rhizoglomus irregularis and Funneliformis mosseae, as well as Trichoderma koningii, were used in this work. The application of endophytic fungi significantly increased total fruit yield by 23.7% compared to that of untreated plants. Multivariate statistics indicated that the biostimulant treatment substantially altered the shape of the metabolic profile of pepper. Compared to the untreated control, the plants treated with microbial biostimulants presented with modified gibberellin, auxin, and cytokinin patterns. The biostimulant treatment also induced secondary metabolism and caused carotenoids, saponins, and phenolic compounds to accumulate in the plants. Differential metabolomic signatures indicated diverse and concerted biochemical responses in the plants following the colonization of their roots by beneficial microorganisms. The above findings demonstrated a clear link between microbial-mediated yield increase and a strong up-regulation of hormonal and secondary metabolic pathways associated with growth stimulation and crop defense to environmental stresses

Impact of sequence variation in the ul128 locus on production of human cytomegalovirus in fibroblast and epithelial cells

The human cytomegalovirus (HCMV) virion envelope contains a complex consisting of glycoproteins gH and gL plus proteins encoded by the UL128 locus (UL128L): pUL128, pUL130, and pUL131A. UL128L is necessary for efficient infection of myeloid, epithelial, and endothelial cells but limits replication in fibroblasts. Consequently, disrupting mutations in UL128L are rapidly selected when clinical isolates are cultured in fibroblasts. In contrast, bacterial artificial chromosome (BAC)-cloned strains TB40-BAC4, FIX, and TR do not contain overt disruptions in UL128L, yet no virus reconstituted from them has been reported to acquire mutations in UL128L in vitro. We performed BAC mutagenesis and reconstitution experiments to test the hypothesis that these strains contain subtle mutations in UL128L that were acquired during passage prior to BAC cloning. Compared to strain Merlin containing wild-type UL128L, all three strains produced higher yields of cell-free virus. Moreover, TB40-BAC4 and FIX spread cell to cell more rapidly than wild-type Merlin in fibroblasts but more slowly in epithelial cells. The differential growth properties of TB40-BAC4 and FIX (but not TR) were mapped to single-nucleotide substitutions in UL128L. The substitution in TB40-BAC4 reduced the splicing efficiency of UL128, and that in FIX resulted in an amino acid substitution in UL130. Introduction of these substitutions into Merlin dramatically increased yields of cell-free virus and increased cell-to-cell spread in fibroblasts but reduced the abundance of pUL128 in the virion and the efficiency of epithelial cell infection. These substitutions appear to represent mutations in UL128L that permit virus to be propagated in fibroblasts while retaining epithelial cell tropism

Yield and nutritional value of first-cutting alfalfa grown in temperature gradient greenhouses under future climate change scenarios depend on Sinorhizobium meliloti strain

Ponencia presentada a la 51 Reunión Científica de la SEEP celebrada en la Escuela Superior de Ingenieros Agrónomos de la Universidad Pública de Navarra entre el 14 y el 18 de mayo de 2012.El objetivo del estudio fue analizar bajo distintos escenarios de simulación de cambio climático (CO2 y temperatura elevados), el efecto de tres cepas de Sinorhizobium meliloti, en la producción, calidad y digestibilidad in-vitro de la alfalfa. Las alfalfas más productivas en su primer corte durante el mes de noviembre fueron las inoculadas con la cepa 102F34, seguidas por la 102F78 y la 1032GMI. El CO2 y la temperatura elevados aumentaron el contenido en fibras, disminuyendo la digestibilidad invitro de la materia seca en las plantas inoculadas con las cepas 102F78 y 1032GMI. La proteína bruta, un indicador de la calidad del forraje, descendió en condiciones de CO2 y temperatura elevados, independientemente de la cepa inoculada. Si bien las plantas inoculadas con la cepa 102F78 produjeron forraje con mayor concentración de proteína bruta, la mayor digestibilidad obtenida con la cepa 102F34, hizo que de las tres cepas analizadas, sea ésta la más adecuada en el escenario de cambio climático estudiado.Elevated CO2 may decrease alfalfa forage quality and in-vitro digestibility through a drop in crude protein and an enhancement of fibre content. The aim of the present study was to analyze the effect of elevated CO2, elevated temperature and Sinorhizobium meliloti strains on alfalfa yield, forage quality and in-vitro dry matter digestibility. Shoot dry matter under elevated CO2 and temperature was different depending on the S. meliloti strain, with 102F34 inoculated plants being the most productive, followed by 102F78, and then 1032GMI. Plants inoculated with the 102F34 strain did not enhance neutral or acid detergent fibre under elevated CO2 or temperature and hence, in-vitro dry matter digestibility was unaffected. Crude protein content, an indicator of forage quality, was negatively related to shoot yield. Plants inoculated with 102F78 showed a similar shoot yield to those inoculated with 102F34, but had higher crude protein content at elevated CO2 and temperature. Under these climate change conditions, 102F78 inoculated plants produced more quality forage. However, the higher digestibility of plants inoculated with the 102F34 strain under any CO2 or temperature conditions, makes them more suitable for growing under applied experimental climate change conditions.Ministerio de Ciencia e Innovación (MICINN BFU2008-01405 y BFU2011-26989), Fundación Universitaria de Navarra (PIUNA-2008), Fundación Caja Navarra y Asociación de Amigos de la Universidad de Navarra

Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV

The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8  TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum