Volatile isoprenoid emission potentials are correlated with essential isoprenoid concentrations in five plant species

This study offers new insight and data in support of the “opportunist hypothesis”. Five species of volatile isoprenoid-emitting plants (Eucalyptus globulus, Eucalyptus gunnii, Mucuna pruriens, Lycopersicon esculentum and Quercus ilex) were exposed to a wide range of imposed and natural stress conditions over a period of a few weeks in order to generate different levels of isoprenoid production potential. Volatile isoprenoid emissions and carotenoid concentrations were measured in all species and dimethylallyl diphosphate (DMAPP) concentrations were measured in E. globulus, E. gunnii, M. pruriens and L. esculentum. Generally, instantaneously emitted isoprenoid emissions were positively correlated with carotenoid concentrations, and were negatively correlated with DMAPP concentrations. In contrast, stored monoterpene emission potentials were negatively correlated with carotenoid concentrations, and positively correlated with DMAPP concentrations. These results support the possibility of a direct or indirect control of volatile isoprenoid emission potential via carotenoid synthesis at time scales of days to weeks

Biogeography of species richness gradients:Linking adaptive traits, demography and diversification

Here we review how adaptive traits contribute to the emergence and maintenance of species richness gradients through their influence on demographic and diversification processes. We start by reviewing how demographic dynamics change along species richness gradients. Empirical studies show that geographical clines in population parameters and measures of demographic variability are frequent along latitudinal and altitudinal gradients. Demographic variability often increases at the extremes of regional species richness gradients and contributes to shape these gradients. Available studies suggest that adaptive traits significantly influence demographic dynamics, and set the limits of species distributions. Traits related to thermal tolerance, resource use, phenology and dispersal seem to play a significant role. For many traits affecting demography and/or diversification processes, complex mechanistic approaches linking genotype, phenotype and fitness are becoming progressively available. In several taxa, species can be distributed along adaptive trait continuums, i.e. a main axis accounting for the bulk of inter-specific variation in some correlated adaptive traits. It is shown that adaptive trait continuums can provide useful mechanistic frameworks to explain demographic dynamics and diversification in species richness gradients. Finally, we review the existence of sequences of adaptive traits in phylogenies, the interactions of adaptive traits and community context, the clinal variation of traits across geographical gradients, and the role of adaptive traits in determining the history of dispersal and diversification of clades. Overall, we show that the study of demographic and evolutionary mechanisms that shape species richness gradients clearly requires the explicit consideration of adaptive traits. To conclude, future research lines and trends in the field are briefly outlined

Differences in photosynthesis and terpene content in leaves and roots of wild-type and transgenic Arabidopsis thaliana plants

We investigated the hypotheses that two different varieties of Arabidopsis thaliana show differences in physiology and terpene production. The two varieties of A. thaliana used in this study were wild-type (WT) and transgenic line (CoxIV-FaNES I) genetically modified to emit nerolidol with linalool/nerolidol synthase (COX). Photosynthetic rate, electron transport rate, fluorescence, leaf volatile terpene contents and root volatile terpene contents were analyzed. For both types, we found co-eluting α-pinene+β-ocimene, limonene, and humulene in leaves; and in the roots we found co-eluting α-pinene+β-ocimene, sabinene+β-pinene, β-myrcene, limonene, and humulene. At the end of the growing cycle, COX plants tended to have lower pools of terpene compounds in their leaves, with 78.6% lower photosynthesis rates and 30.8% lower electron transport rates, compared with WT plants at that time. The maximal photochemical efficiency Fv/Fm was also significantly lower (25.5%) in COX plants, indicating that these varieties were more stressed than WT plants. However, COX plants had higher (239%) root terpene contents compared to WT plants. COX plants appear to favor root production of volatile terpenes rather than leaf production. Thus we conclude that there were significant differences between COX and WT plants in terms of terpenoid pools, stress status and physiology

RENDIMIENTO, COMPOSICION QUIMICA Y PRODUCCION DE GAS IN VITRO DE DIFERENTES VARIEDADES DE MAICES HIBRIDOS EN FRESCO, HENO Y CONSERVADOS COMO ENSILAJE CON UN ADITIVO QUIMICO Y ENZIMAS.

El objetivo de este estudio fue evaluar el rendimiento, la composición química y la producción de gas in vitro de 17 variedades de híbridos de maíz (11 híbridos blancos: Aspros 723, Búho, CML 457/458, Cromo, H40, H47E, H51EA, H66, H70, Hit7 y Victoria; 6 híbridos amarillos: HIT13, CML460, PIONER, COBRE, CDMO80001 y CLO80902) y dos criollos locales: un blanco (CLB) y un amarillo (CLA) cultivados en valles altos de México, en fresco, heno y conservados por ensilaje, con tres tratamientos: control (CTR), ácido acético al 1 % (AAC), o enzimas (ENZ), Sil all ® 10g/ton. Para los maíces blancos se encontraron diferencias en el rendimiento (P˂0.05) en fresco y en heno, con rendimientos de 60 a 117 ton/ha para fresco y de 17 a 29 ton/ha para heno respectivamente, en cuanto a su composición química (g/kg MS) mostraron diferencias (P˂0.05) para proteína, donde su concentración vario de 44 a 62 g/kg MS, FND de 581 a 629 g/kg MS y FAD de 297 a 344 g/kg MS; la producción de gas in vitro mostro diferencias (P˂0.05) para las fracciones b, c y lag time. No se encontraron diferencias (P˃0.05) para la materia seca desaparecida (612 a 669 g /kg MS). Se concluye que de acuerdo con los resultados obtenidos, las variedades H51EA, H47E y CLB son superiores con respecto al resto de las variedades estudiadas. Para las variedades de maíz amarillo el rendimiento en fresco y en seco no mostro diferencias entre tratamientos (P˃0.05), en cuanto a su composición química (g/kg MS) mostraron diferencias (P˂0.05) para proteína, donde su concentración vario de 54 a 74 g/kg MS, FND de 512 a 699 g/kg MS y FAD de 287 a 338 g/kg MS; la producción de gas in vitro mostro diferencias (P˂0.05) en cuanto a tratamientos de las 3 a 18 h de incubación, no así (P>0.05) para las 24 y 30 h, por variedad mostro diferencias (P˂0.05) a las 12 h siendo superior la variedad CLO80902 e inferior la variedad CML460; Se elaboraron micro-silos de diez variedades (n = 90), con tres tratamientos Ácido acético al 1 % (AAC), o enzimas, Sil All®10g/ton(ENZ) y control (CTR); Después de 60 días, se abrieron las micro-silos. Una vez obtenidos los resultados la matriz de datos se analizó utilizando dos técnicas multivariantes ([i] Las variables consideradas para el análisis de componentes Principales y [ ii ] El análisis jerárquico de conglomerados). La primera técnica multivariante se usó parareducir la información y definir los factores importantes. El análisis de conglomerados muestra la presencia de cuatro grupos con características diferentes entre los grupos: G1 como ensilados con energía (variedades H47 y Pioneer), G2 ensiladoscon proteína (variedades Cromo, H66 y Victoria), G3 ensilados de fácil degradabilidad (variedades Cobre y HIT7), y G4 ensilados balanceados (variedades Búho, H40, H70). Los tratamientos AAC y ENZ en G2, y ENZ en G3 fueron más altos en el contenido de proteína cruda (PC) que el resto de los tratamientos. Los tratamientos con ENZ en G1, G2 y G3 tuvieron el contenido más alto de fibra neutro detergente (FND) (P<0,01). Los contenidos de energía metabolizable (ME) y energía neta para lactación (ENl) fueron mayores para G1 tratado con AAC, ENZ y CTR y G2 CTR que el resto de la tratamientos. El pH más bajo (P < 0,01) fue para G2 y G4 tratados con AAC y CTR, en comparación con G1 y G2 tratados con AAC y ENZ.La producción de gas in vitro (ml gas/gMS) fue mayor (P<0,05) para G3 y G4 tratados con ENZ en comparación con G1 CTR y AAC. No hubo diferencias (P > 0,05) en la digestibilidad de la materia seca in vitro, pero la digestibilidad de la FDN fue mayor (P < 0,01) para G1 tratado con CTR, AAC y ENZ , G2 tratado con CTR , y G4 tratado con ENZ que el resto de los tratamientos . Como conclusión, el estudio muestra que tenemos cuatro grupos, dependiendo de su concentración de nutrientes, ensilajes con energía (G1) , ensilajes con proteínas (G2) , ensilajes de fácil degradabilidad (G3) y ensilajes Balanceados (G4) que podemos usar como fuentes de alimentación para el ganado

1000 fps computational ghost imaging using LED-based structured illumination

: Single-pixel imaging uses a single-pixel detector, rather than a focal plane detector array, to image a scene. It provides advantages for applications such as multi-wavelength, three-dimensional imaging. However, low frame rates have been a major obstacle inhibiting the use of computational ghost imaging technique in wider applications since its invention one decade ago. To address this problem, a computational ghost imaging scheme, which utilizes an LED-based, high-speed illumination module is presented in this work. At 32 × 32 pixel resolution, the proof-of-principle system achieved continuous imaging with 1000 fps frame rate, approximately two orders larger than those of other existing ghost imaging systems. The proposed scheme provides a cost-effective and high-speed imaging technique for dynamic imaging application

On Parameterizing Soil Evaporation in a Direct Remote Sensing Model of ET: PT-JPL

Remote sensing models that measure evapotranspiration directly from the Penman-Monteith or Priestley-Taylor equations typically estimate the soil evaporation component over large areas using coarse spatial resolution relative humidity (RH) from geospatial climate datasets. As a result, the models tend to underperform in dry areas at local scales where moisture status is not well represented by surrounding areas. Earth observation sensors that monitor large-scale global dynamics (e.g., MODIS) afford comparable spatial coverage and temporal frequency, but at a higher spatial resolution than geospatial climate datasets. In this study, we compared soil evaporation parameterized with optical and thermal indices derived from MODIS to RH-based soil evaporation as implemented in the Priestley Taylor-Jet Propulsion Laboratory (PT-JPL) model. We evaluated the parameterizations by subtracting PT-JPL transpiration from observation-based flux tower evapotranspiration in agricultural fields across the contiguous United States. We compared the apparent thermal inertia (ATI) index, land surface water index (LSWI), normalized difference water index (NDWI), and a new index derived from red and shortwave infrared bands (soil moisture divergence index [SMDI]). Relationships were significant at the 95% confidence band. LSWI and SMDI explained 18–33% of variance in 8-day soil evaporation. This led to a 3–11% increase in explained ET variance. LSWI and SMDI tended to perform better at the irrigated sites than RH. LSWI and SMDI led to markedly better performance over other indices at a seasonal time step. L-band microwave backscatter can penetrate clouds and can distinguish soil from canopy moisture content. We are presently fusing red-SWIR-RADAR to improve soil evaporation estimation.Fil: Marshall, Michael. University of Twente. Faculty of Geo‐information Science and Earth Observation. Department of Natural Resources; Países BajosFil: Tu, Kevin. Corteva Agriscience; Estados UnidosFil: Andreo, Verónica Carolina. Comision Nacional de Actividades Espaciales. Instituto de Altos Estudios Espaciales "Mario Gulich"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentin

Is forest fecundity resistant to drought? Results from an 18-yr rainfall-reduction experiment

Recruitment is a primary determinant of the long-term dynamics of plant populations in changing environments. However, little information is known about the effects of anthropogenic environmental changes on reproductive ecology of trees. We evaluated the impact of experimentally induced 18 yr of drought on reproduction of three contrasting forest trees: Quercus ilex , Phillyrea latifolia and Arbutus unedo. Rainfall reduction did not decrease tree fecundity. Drought, however, affected the allocation of resources in Q. ilex and A. unedo but not the more drought tolerant P. latifolia. Larger crop production by Q. ilex and A. unedo was associated with a stronger decrease in growth in the rainfall-reduction plots compared with the control plots, suggesting that these species were able to maintain their fecundity by shifting their allocation of resources away from growth