The complete chloroplast genome sequence of <i>Ammodendron bifolium</i> (Fabaceae), an endangered desert shrub from China

Ammodendron bifolium, a rare deciduous shrub, is the only species of Ammodendron (Fabaceae) in China, which distributes in Huocheng county, Xinjiang. This study employed high-throughput sequencing technology to assemble the complete chloroplast genome sequence of A. bifolium. The entire length of chloroplast genome is 154,426 bp. It comprises 128 genes, which include 85 protein-coding genes, 35 tRNA genes, and 8 rRNA genes. The A. bifolium chloroplast genome has a GC content of 36.41%. Phylogenetic analysis strongly supported that A. bifolium is sister to the members of the Sophora genus. This study will provide the genetic information data for further phylogenetic studies of Ammodendron.</p

Analysis of variance for plant traits of four species under soil nutrients, water, and population densities.

<p><i>F</i>-values are presented.</p>*<p>refers to significance at <i>P</i><.05;</p>**<p>to significance at <i>P</i><.01;</p>***<p>to significance at <i>P</i><.001.</p

Log10-log10 plots showing the relationship between reproductive biomass and vegetative biomass of (a) <i>A. squarrosum</i> (black), <i>C. macrocarpum</i> (red), <i>C. acuminatum</i> (green) and <i>S. collina</i> (blue); and SMA fit line for combining all early successional species (cyan dashed line) and combining all late successional species (magenta solid line).

<p>For b (soil nutrient treatments), c (soil water treatments), and d (population density treatments), low environmental level (circle points and solid line) and high soil nutrient treatment level (triangle points and dashed line), black, red, green and blue, respectively for <i>A. squarrosum</i>, <i>C. macrocarpum</i>, <i>C. acuminatum</i> and <i>S. collina</i>, and SMA fit line for combining all low environmental levels (cyan dashed line) and combining all high environmental levels (magenta solid line).</p

Table_2.PDF

<p>Since seed reserves can influence seed germination, the quantitative and qualitative differences in seed reserves may relate to the germination characteristics of species. The purpose of our study was to evaluate the correlation between germination and seed reserves, as well as their mobilization during germination of six grassland species (Chloris virgata, Kochia scoparia, Lespedeza hedysaroides, Astragalus adsurgens, Leonurus artemisia, and Dracocephalum moldavica) and compare the results with domesticated species. We measured starch, protein, and fat content in dry seeds and the initial absorption of water during imbibition. Starch, soluble protein, fat, and soluble sugar content also were determined at five stages during germination. Starch, protein, and fat reserves in dry seeds were not significantly correlated with germination percentage and rate (speed), but soluble sugar and soluble protein contents at different germination stages were positively significantly correlated with germination rate for the six species. Starch was mainly used during seed imbibition, and soluble protein was used from the imbibition stage to the highest germination stage. Fat content for all species remained relatively constant throughout germination for six species, regardless of the proportion of other seed reserves in the seeds. Our results for fat utilization differ from those obtained for cultivated grasses and legumes. These results provide new insight on the role of seed reserves as energy resources in germination for wild species.</p

Results of standardized major axis regression (SMA) analysis of pairwise combinations of reproductive biomass and vegetative biomass for each species in different treatments.

<p><i>P</i>1 is the test of slope homogeneity, <i>P</i>2 is the test of shift in elevation, <i>P</i>3 is the test of Shift along slope. Significant results (P<0.05) are shown in bold.</p

Norm of reaction for four species at two soil nutrients (N), water (W) and population density (D) levels on total biomass and reproductive effort of four species; + and − indicate two levels of factor.

<p>The data represent means ± SD of average across treatments; Asterisks denote significance at <i>P</i>>0.05 (ns), <i>P</i><0.05 (*), <i>P</i><0.01 (**) and <i>P</i><0.001 (***) for each species in different level environmental treatment; the same lower case letters within columns are not significantly different at <i>P</i><0.05 in low level environmental treatments for four species; Same capital letters within columns are not significantly different at <i>P</i><0.05 in high level environmental treatment for four species. Sig, the <i>P</i> value of interactions of between total biomass and environmental factor when compared between <i>C. acuminatum</i> and early succession species (<i>A. squarrosum</i> and <i>C. macrocarpum</i>) and between <i>S. collina</i> and early succession species (<i>A. squarrosum</i> and <i>C. macrocarpum</i>).</p

Table_1.PDF

<p>Since seed reserves can influence seed germination, the quantitative and qualitative differences in seed reserves may relate to the germination characteristics of species. The purpose of our study was to evaluate the correlation between germination and seed reserves, as well as their mobilization during germination of six grassland species (Chloris virgata, Kochia scoparia, Lespedeza hedysaroides, Astragalus adsurgens, Leonurus artemisia, and Dracocephalum moldavica) and compare the results with domesticated species. We measured starch, protein, and fat content in dry seeds and the initial absorption of water during imbibition. Starch, soluble protein, fat, and soluble sugar content also were determined at five stages during germination. Starch, protein, and fat reserves in dry seeds were not significantly correlated with germination percentage and rate (speed), but soluble sugar and soluble protein contents at different germination stages were positively significantly correlated with germination rate for the six species. Starch was mainly used during seed imbibition, and soluble protein was used from the imbibition stage to the highest germination stage. Fat content for all species remained relatively constant throughout germination for six species, regardless of the proportion of other seed reserves in the seeds. Our results for fat utilization differ from those obtained for cultivated grasses and legumes. These results provide new insight on the role of seed reserves as energy resources in germination for wild species.</p

Results of standardized major axis regression (SMA) analysis of pairwise combinations of reproductive biomass and vegetative biomass for combining all species in different treatments.

<p>Significant results (P<0.05) are shown in bold.</p

Norm of reaction for four species at two soil nutrients (N), water (W) and population density (D) levels on morphological traits; + and − indicate two levels of factor; The data represent means ± SD of average across treatments; ns denote not significance (<i>P</i>>0.05), asterisks denote significance at <i>P</i><0.05 (*), <i>P</i><0.01 (**) and <i>P</i><0.001 (***) for each species in different level environmental treatments; the same lower case letters within columns are not significantly different at <i>P</i><0.05 in low level environmental treatment for four species; the same capital letters within columns are not significantly different at <i>P</i><0.05 in high level environmental treatments for four species.

<p>Sig, the <i>P</i> value of interactions between traits and environmental factors when compared between <i>C. acuminatum</i> and early succession species (<i>A. squarrosum</i> and <i>C. macrocarpum</i>) and between <i>S. collina</i> and early succession species (<i>A. squarrosum</i> and <i>C. macrocarpum</i>).</p

Biofouling Removal and Protein Detection Using a Hypersonic Resonator

Nonspecific binding (NSB) is a general issue for surface based biosensors. Various approaches have been developed to prevent or remove the NSBs. However, these approaches either increased the background signals of the sensors or limited to specific transducers interface. In this work, we developed a hydrodynamic approach to selectively remove the NSBs using a microfabricated hypersonic resonator with 2.5 gigahertz (GHz) resonant frequency. The high frequency device facilitates generation of multiple controlled microvortexes which then create cleaning forces at the solid–liquid interfaces. The competitive adhesive and cleaning forces have been investigated using the finite element method (FEM) simulation, identifying the feasibility of the vortex-induced NSB removal. NSB proteins have been selectively removed experimentally both on the surface of the resonator and on other substrates which contact the vortexes. Thus, the developed hydrodynamic approach is believed to be a simple and versatile tool for NSB removal and compatible to many sensor systems. The unique feature of the hypersonic resonator is that it can be used as a gravimetric sensor as well; thus a combined NSB removal and protein detection dual functional biosensor system is developed