Summary• The fine-scale spatial distribution of a wild soybean ( Glycine soja Sieb. et Zucc) population was measured using kinship coefficients and spatial autocorrelation coefficients to reveal fine-scale spatial patterns of genetic structure for guiding collection in ex situ conservation.• Individual families (100) of a single population were sampled in Jiangwan (Shanghai, China) and their specific locations mapped. Individual plants were genotyped for 331 ISSR loci from 15 selective ISSR primers; 45% were demonstrated to be polymorphic.• Pairwise kinship coefficients between individuals were calculated, and then regressed based on the spatial distance between individuals. The results indicated a close genetic relationship among individual families in the patch with a diameter of c. 30 m. Spatial autocorrelation analysis suggested that there were significant clusters of genes within the population; c. 81.4% of the loci were found to be positively correlated in the first two distance classes (0 -10 m).• The results suggest, for conservation genetics, sampling within a wild soybean population should be conducted at 10 m intervals across the entire population to optimize the genetic diversity in collections taken from that population.

We present transmissive plasmonic structural colors from subwavelength nanohole arrays with bottom metal disks for scaled-up manufacturing by nanoimprint lithography (NIL). Comprehensive theoretical and experimental studies are carried out to understand the specific extraordinary optical transmission behavior of the structures with such bottom metal disks. Distinctive colors covering the entire visible spectrum can be generated by changing the structural dimensions of hole arrays in Ag covered by the metal disks. The plasmonic energy hybridization theory is applied to explain the unstable color output with shallow holes so that a large processing window during NIL could be achieved for mass production. A high-resolution of 127,000 dots per inch is demonstrated with potential applications, including color filters and displays, high-resolution color printing, CMOS color imaging, and anti-counterfeiting.

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An improved architecture for all-Si based photoelectronic detectors has been developed, consisting of a specially designed metasurface as the antenna integrated into a Si nanowire array on the insulator by an electron beam lithography based self-alignment process. Simulation using the Finite Difference Time Domain (FDTD) method was carried out to ensure perfect absorption of light by the detector. Optic measurement shows a 90% absorption at 1.05 μm. Photoelectronic characterization demonstrates the responsivity and detectivity as high as 94.5 mA/W and 4.38 × 1011 cm Hz1/2/W, respectively, at 1.15 μm with the bandwidth of 480 nm, which is comparable to that of III–V/II–VI compound detectors. It is understood that the outstanding performances over other reported all-Si based detectors originate from the enhanced quantum efficiency in one-dimensional conduction channels with high density of states, which efficiently accommodate the emitted plasmonic hot electrons for high conduction in the Si nanowires, enabling the near-infrared detection by all-Si based detectors.

The aim of this study was to characterize the Italian rice (Oryza sativa L.) gene pool, paying particular attention to its variation over time, to determine whether human activity can reduce genetic variability, and whether such a reduction actually occurred in Italian rice varieties. We analyzed 135 Italian rice accessions, representing genotypes either introduced from abroad or developed in Italy from 1880 to 2001, using two groups of molecular markers, amplified fragment length polymorphisms and simple sequence repeats. These accessions were divided into four groups for which different statistical analyses were performed. The levels of gene diversity, from 0.1023 to 0.1921, and genetic richness, from 0.1579 to 0.3064, increased over time. Genetic structure, as estimated by analysis of molecular variance, revealed that the within‐component was overwhelmingly dominant (92%) compared with the among‐component. These results show that the level of genetic diversity in Italian rice accessions has remained high since 1850 and continues to increase. This is most likely the result of Italian breeding programs that developed new cultivars and introduced others from abroad, without substituting previous accessions. Our results show that the management and improvement of rice germplasm in Italy have been successful in maintaining sufficient genetic diversity.