Emergence of the pointer basis through the dynamics of correlations

We use the classical correlation between a quantum system being measured and its measurement apparatus to analyze the amount of information being retrieved in a quantum measurement process. Accounting for decoherence of the apparatus, we show that these correlations may have a sudden transition from a decay regime to a constant level. This transition characterizes a non-asymptotic emergence of the pointer basis, while the system-apparatus can still be quantum correlated. We provide a formalization of the concept of emergence of a pointer basis in an apparatus subject to decoherence. This contrast of the pointer basis emergence to the quantum to classical transition is demonstrated in an experiment with polarization entangled photon pairs.Comment: 4+2 pgs, 3 figures. Title changed. Revised version to appear on PR

Zinc and cadmium accumulation in controlled crosses between metallicolous and nonmetallicolous populations of Thlaspi caerulescens (Brassicaceae)

International audience# Growth and heavy metal (Zn and Cd) hyperaccumulation were investigated in metallicolous and nonmetallicolous Mediterranean populations of Thlaspi caerulescens (Brassicaceae), and in offspring from controlled crosses between these populations. # • Seeds for the growth and crossing experiments were collected from a number of sites varying in heavy metal contamination. Tissue Zn and Cd content was determined by atomic absorption spectrophotometry. # • Offspring from crosses between nonmetallicolous populations had the highest Zn concentration (c. 30 000 µg g−1), compared with 20 000 µg g−1 for the nonmetallicolous parents. The metallicolous parents and the other crosses had only 10 000 µg g−1. Offspring from crosses including a nonmetallicolous parent still had a significantly higher Zn uptake than the metallicolous parents. A trend towards a higher Cd uptake was observed in offspring from crosses with a metallicolous parent. # • We suggest that the most probable hypothesis is that the differences in Zn hyperaccumulation between crosses could be explained by a monogenic system with two alleles. The dominant allele would restrict Zn hyperaccumulation at 10 000 µg g−1 whereas the recessive allele would be responsible for a two to three-fold increase in Zn hyperaccumulation. Alternatively, the existence of modifier genes could explain the differences between offspring from crosses between nonmetallicolous populations and their respective field parents. The results suggest that plant breeding applied to this species could help to improve Zn phytoextraction

Bruchid resistance in pulses

National audienc

Towards bruchid resistance in pulses

National audienceSeed weevils (Bruchus spp.) are major pests of pulses, causing yield losses and affecting marketability 1,2 . Available insecticides have low efficiency and important negative impacts on the environment, humans and non-target organisms. Therefore, breeding resistant varieties represent the most promising strategy to overcome seed weevils. The pyramiding of several resistance genes in cultivars is an important objective because this will make the resistance more durable and suitable for sustainable agriculture. The PeaMUST project (ANR-11-BTBR0002) aims at discovering the mechanisms of tolerance and resistance to bruchids in pea (Pisum sativum L.) and faba bean (Vicia faba L.) crops and identifying the functional candidate genes for future implementation in Genomics-Assisted Breeding (GAB). A multidisciplinary approach that includes Genome- Wide Association Studies (GWAS), Quantitative trait locus (QTLs) mapping, RNA sequencing (RNA-Seq), shotgun proteomics and Volatile Organic Compounds (VOCs) analysis has been used to identify potential candidate genes for resistance to bruchids. The results will provide (i) original basic knowledge about resistance strategies in pea and faba bean, the candidate genes underlying quantitative resistance to bruchids and its conservation in other legume species, as well as, (ii) innovative applied knowledge and tools for breeding pea and faba bean varieties resistant to bruchids, which will be useful in future strategies of durable resistance management