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European breeding programs are hampered by the low intraspecific genetic diversity, which is due to the self-compatibility of this homozygous species along with the low number of genotypes introduced and thus used for breeding. In 2009, four research institutions which carried out peach breeding programs in Aragon, Catalonia, Valencia and Murcia, started a new peach germplasm collection worldwide aimed at enlarging the peach genetic diversity available for breeding. The plant material was introduced from germplasm collections located in China, Central Asia, Iran and the USA (National Germplasm Repository of Davis). Sanitary status was assessed by molecular diagnosis of known diseases caused by virus, viroid, bacteria and phytoplasm pathogens. Healthy plant material was grafted and maintained in quarantine conditions. The new germplasm collection was established in two places: Zaragoza as high chilling and Murcia as low chilling requirements. Pomological and molecular data were gathered and a public database constructed. The descriptors used were from the National Center for Genetic Resources from the INIA. Introduced budwood and seeds resulted in more than 250 new genotypes from 15 countries. The molecular analysis of a subset of the collection with 21 SSR markers evenly distributed in the genome resulted in a high number of alleles per SSR (mean A=9.5) and low observed heterozygosity (mean Ho=0.38). Variability was further assessed by geographic origin. Population structure analysis revealed the existence of 8 subpopulations explained, in some cases, by the geographic origin of the genotypes. As a result of the project a new database containing 95 accessions and 38 variables is available.

Background: The reproductive phenology of perennial plants in temperate climates is largely conditioned by the duration of bud dormancy, and fruit developmental processes. Bud dormancy release and bud break depends on the perception of cumulative chilling and heat during the bud development. The objective of this work was to identify new quantitative trait loci (QTLs) associated to temperature requirements for bud dormancy release and flowering and to fruit harvest date, in a segregating population of peach. Results: We have identified QTLs for nine traits related to bud dormancy, flowering and fruit harvest in an intraspecific hybrid population of peach in two locations differing in chilling time accumulation. QTLs were located in a genetic linkage map of peach based on single nucleotide polymorphism (SNP) markers for eight linkage groups (LGs) of the peach genome sequence. QTLs for chilling requirements for dormancy release and blooming clustered in seven different genomic regions that partially coincided with loci identified in previous works. The most significant QTL for chilling requirements mapped to LG1, close to the evergrowing locus. QTLs for heat requirement related traits were distributed in nine genomic regions, four of them co-localizing with QTLs for chilling requirement trait. Two major loci in LG4 and LG6 determined fruit harvest time. Conclusions: We identified QTLs associated to nine traits related to the reproductive phenology in peach. A search of candidate genes for these QTLs rendered different genes related to flowering regulation, chromatin modification and hormone signalling. A better understanding of the genetic factors affecting crop phenology might help scientists and breeders to predict changes in genotype performance in a context of global climate change.

We report measurements of differential cross sections for elastic electron scattering from CF3. These experiments were performed at nine incident electron energies in the range 7-50 eV and over a scattered electron angular range of 20°-135°. Where possi

Using a crossed electron-molecular-beam apparatus, absolute elastic cross sections for electron scattering from the CF3 molecule were measured. Differential cross sections were determined for incident electron energies in the range 7-50 eV and over an ang

[EN] Hand thinning is a necessary but costly practice in peach (Prunus persica L. Batsch) production. A hand-held mechanical device has been tested to thin peach trees, trained in " free Italian vase" , 50-62days after full bloom. Hand thinning (HT); mechanical thinning (MT); mechanical and hand thinning (MHT); and un-thinned (UT) were tested from 2008 to 2011 in Murcia, south-eastern Spain. After thinning, the distance between the remaining fruits was measured: the shortest distance was 5.2cm for MT, with no significant differences between MHT and HT at 8.6 and 8.8cm, respectively. The differences in distances did not affect the yield and size of the fruit at harvesting in any of the cases. There were no significant differences between HT, MT and MHT treatments in fruit per tree, mean fruit weight and yield efficiency in the 4years the test lasted. Farmers considered the hand-held mechanical device positively because it increased field efficiency. Moreover, with HT the operating time was 291hha -1, with MHT it was 87hha -1 and with MT, 27hha -1. The most expensive system was HT (2442€ha -1) as opposed to 824€ha -1 for MHT. The lowest cost was for MT with 296€ha -1. The net value of fruit (€ha -1) showed no significant differences between HT, MT, and MHT. Based on our study, MT appears to be a promising technique for thinning peach trees for the canning industry, because although the reduction of production costs is not high in comparison with the total cost of the crop, the increase in work speed is of great interest to thin the trees on the most appropriate dates. © 2012 Elsevier B.V.

[EN] The use of hand-held mechanical devices to thin blooms of peach trees trained into the " free Italian vase" form was studied. Three devices were tested, and no differences were found among them in terms of thinning time and number of fruits per cm 2 of trunk cross-sectional area (TCSA) at harvesting. Thinning, by hand or mechanically, reduced the yield per tree by 26-33% with respect to not thinning; however, thinning increased the fruit size. In both years, the yields of fruit >67mm in the thinned trees ranged from 40.4 to 53.4kgtree -1, respectively, whereas in the un-thinned trees, it was 25.1 and 18.2kgtree -1 in 2009 and 2010, respectively. Hand thinning took 385hha -1, and mechanical thinning reduced this time by 89%. The cost of hand thinning was 4.8z€tree -1, whereas the cost of mechanical thinning ranged from 0.4 to 1.1z€tree -1. The economic study showed that the total yield value was similar with hand and mechanical thinning, but the cost of mechanical thinning was only 10-18% that of hand thinning. © 2011 Elsevier B.V.

We present results from a joint experimental and theoretical study of elastic electron scattering from atomic iodine. The experimental results were obtained by subtracting known cross sections from the measured data obtained with a pyrolyzed mixed beam containing a variety of atomic and molecular species. The calculations were performed using both a fully relativistic Dirac B-spline R-matrix (close-coupling) method and an optical model potential approach. Given the difficulty of the problem, the agreement between the two sets of theoretical predictions and the experimental data for the angle-differential and the angle-integrated elastic cross sections at 40 eV and 50 eV is satisfactory.

Experimental results are reported for elastic differential and integral cross sections for electrons scattering from iodomethane (CH3I). These measurements were made at seven incident electron energies in the range 5-50 eV, with a scattered electron angular range of 20°-135°. Corresponding calculations using the independent atom method plus screened additivity rule (IAM-SCAR), both with and without a dipole correction, are also reported as a part of this study. Where possible, comparison is made to the only other set of experimental results available in the literature (Kato et al 2010 J. Chem. Phys. 132 074309) and to calculated cross sections from the Schwinger multichannel approach at the static exchange level (Natalense et al 2001 Braz. J. Phys. 31 15). In general, good agreement is found between the present measurements and IAM-SCAR computations, and between our results and the earlier investigations.

Electron interaction cross sections for species found in low-temperature industrial plasma environments are a crucial component to allow for accurate modeling of those plasmas. However, such data are still rarely reported in the literature, due to the complexities of working with such highly reactive species in a laboratory. Here, absolute differential cross section measurements for a 'plasma-like' gas mixture, containing CF3I, CF3, I2, I and C2F6, are reported.

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