Optimizing planting density for production of high-quality apple nursery stock in China

<div><p>In China, apple (<i>Malus</i> × <i>domestica</i> Borkh.) nursery stock is generally of low quality because of extremely high planting density. The objective of this study was to determine the optimum planting density of 2-year-old grafted apple trees. Tree growth (height, trunk diameter, leaf area index) increased as density decreased. Trees grown at high densities (14.3–50 plants/m²) were the shortest with the smallest trunk diameters and leaf areas, whereas trees grown at lower densities (4.8–10 plants/m²) were generally largest in terms of height, diameter and leaf area. Trees grown at lower densities tended to have higher bud dry weight, leaf dry weight, nitrogen content, total soluble sugar concentration and total non-structural carbohydrate content. Higher levels of these parameters were generally observed with tree densities at or below 10 plants/m². Therefore we conclude that 10 plants/m² is the optimum density for maximizing the number of trees produced per unit land area while maintaining tree quality of nursery stock.</p></div

Coherent diffraction of single Rice Dwarf virus particles using hard X-rays at the Linac Coherent Light Source

Single particle diffractive imaging data from Rice Dwarf Virus (RDV) were recorded using the Coherent X-ray Imaging (CXI) instrument at the Linac Coherent Light Source (LCLS). RDV was chosen as it is a well-characterized model system, useful for proof-of-principle experiments, system optimization and algorithm development. RDV, an icosahedral virus of about 70 nm in diameter, was aerosolized and injected into the approximately 0.1 μm diameter focused hard X-ray beam at the CXI instrument of LCLS. Diffraction patterns from RDV with signal to 5.9 Ångström were recorded. The diffraction data are available through the Coherent X-ray Imaging Data Bank (CXIDB) as a resource for algorithm development, the contents of which are described here