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Although root architecture has been shown to play an important role in crop performance, particularly under drought conditions, no information is available on the genetic control of root traits in durum wheat, a crop largely grown in rainfed areas with low rainfall. In our study, a panel of 57 elite durum wheat accessions were evaluated under controlled conditions for root and shoot traits at the seedling stage. Significant genetic variability was detected for all the root and shoot traits that were investigated. Correlation analysis suggested that root and shoot features were only partially controlled by common sets of genes. The high linkage disequilibrium (up to 5 cM) present in the germplasm collection herein considered allowed us to use simple sequence repeat-based association mapping to identify chromosome regions with significant effects on the investigated traits. In total, 15 chromosome regions showed significant effects on one or more root architectural features. A number of these regions also influenced shoot traits and, in some cases, plant height measured in field conditions. Major effects were detected on chromosome arms 2AL (at Xgwm294), 7AL (at Xcfa2257 and Xgwm332) and 7BL (at Xgwm577 and Xcfa2040). The accessions with the most remarkable differences in root features will provide a valuable opportunity to assemble durum wheat mapping populations well suited for ascertaining the effects of root architecture on water use efficiency and grain yield.

Since 1999, a disease of apple caused by an Alternaria sp. has been affecting orchards in northern Italy resulting in necrotic spots on leaves and on fruit. Forty-four single-spored isolates were obtained from diseased plant materials to investigate the diversity of this fungus in Italy and to compare these isolates to isolates of Alternaria associated with apple disease in previous studies, including A. mali, causal agent of apple blotch. All isolates, including the reference strains, were tested for pathogenicity utilizing in vitro bioassays on detached leaf or on fruit ('Golden Delicious'). In addition, morphological characterizations were conducted describing both the three-dimensional sporulation pattern and the colony morphology of each isolate. In order to assess the genetic diversity within the Italian Alternaria population, sequence characterization of specific loci and anonymous regions (endoPG, OPA1-3, OPA2-1, and OPA10-2) and genetic fingerprinting based on amplified fragment length polymorphism and inter simple sequence repeat markers were performed. The single spore isolates exhibited differential pathogenicity, which did not correlate with the morphological groupings or to groupings defined by molecular approaches. Moreover, 10 pathogenic isolates out of the 44 single-spored tested were positive for the host-specific AM-toxin gene based upon polymerase chain reaction amplification using specific primers for the AM-toxin gene. This suggests that the production of the AM-toxin may be involved in pathogenesis by some of the Italian isolates of A. alternata from apple. However, this research also suggests that a number of different Alternaria genotypes and morphotypes may be responsible for the apple disease in Italy and that a single taxon cannot be defined as the sole causal agent.

The transformics method was developed to support the integrated testing strategy for carcinogenesis. Results showed the main role of the immune system in the transformation by 3-MCA, with initiating events related to non-genotoxic mechanisms, suggesting the involvement of the AhR receptor.

The determination of genetic relatedness among elite materials of crop species allows for more efficient management of breeding programs and for the protection of breeders' rights. Seventy simple sequence repeats (SSRs) and 234 amplified fragment length polymorphisms (AFLPs) were used to profile a collection of 58 durum wheat (Triticum durum Desf.) accessions, representing the most important extant breeding programs. In addition, 42 phenotypic traits, including the morphological characteristics recommended for the official distinctness, uniformity, and stability tests, were recorded. The correlation between the genetic similarities obtained with the 2 marker classes was high (r = 0.81), whereas lower values were observed between molecular and phenotypic data (r = 0.46 and 0.56 for AFLPs and SSRs, respectively). Morphological data, even if sampled in high numbers, largely failed to describe the pattern of genetic similarity, according to known pedigree data and the indications provided by molecular markers.

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13The fungal genus Alternaria comprises a large number of asexual taxa with diverse ecological, 14 morphological and biological modes ranging from saprophytes to plant pathogens. Understanding 15 the speciation processes affecting asexual fungi is important for estimating biological diversity 16 which in turn affects plant disease management and quarantine enforcement. This study included 17 106 isolates of Alternaria representing five phylogenetically defined clades in two sister sub-18 generic groups; section Porri (A. dauci, A. solani and A. limicola) is not typical of asexual reproducing lineages. A species tree was inferred using a Yule Speciation 28 model and a strict molecular clock assumption. Species boundaries were well defined within 29 section Porri. However, species boundaries within section Alternaria were only partially resolved 30 with no well-defined species boundaries possibly due to incomplete lineage sorting. Significant 31 association with host specifity seems a driving force for speciation. 32 33

A large number of basic researches and observational studies suggested the cancer preventive activity of vitamin E, but large-scale human intervention trials have yielded disappointing results and actually showed a higher incidence of prostate cancer although the mechanisms underlying the increased risk remain largely unknown. Here we show through in vitro and in vivo studies that vitamin E produces a marked inductive effect on carcinogen-bioactivating enzymes and a pro-oxidant status promoting both DNA damage and cell transformation frequency. First, we found that vitamin E in the human prostate epithelial RWPE-1 cell line has the remarkable ability to upregulate the expression of various phase-I activating cytochrome P450 (CYP) enzymes, including activators of polycyclic aromatic hydrocarbons (PAHs), giving rise to supraphysiological levels of reactive oxygen species. Furthermore, our rat model confirmed that vitamin E in the prostate has a powerful booster effect on CYP enzymes associated with the generation of oxidative stress, thereby favoring lipid-derived electrophile spread that covalently modifies proteins. We show that vitamin E not only causes DNA damage but also promotes cell transformation frequency induced by the PAH-prototype benzo[a]pyrene. Our findings might explain why dietary supplementation with vitamin E increases the prostate cancer risk among healthy men. Prostate cancer is the most common human malignancy and the second leading cause of cancer death among men in western nations. The high global incidence of prostate cancer, the unsatisfactory outcomes of surgery and radiotherapy and the cost of curative therapies have led to a focus on primary prevention as a major public health goal 1,2. Supported by preclinical and epidemiological evidence, antioxidants from food and supplements are widely used to protect against cancer, but clinical trials do not sustain this concept 1,3-6 and actually showed a higher incidence of prostate cancer 7,8. Conceived to break through this issue, in 2001 the National Cancer Institute (NCI) launched SELECT (Selenium and vitamin E Cancer Prevention Trial), that showed a 17% increase in prostate cancer incidence in the vitamin E arm compared to placebo 7. A growth-promoting effect of vitamin E on organoids has recently been reported 9 , but its mechanism of action remains poorly understood. Since some cytochrome P-450 (CYP) isoforms have been found overexpressed in prostate cancer 10-15 , we suspected that vitamin E could have co-carcinogenic properties such as those involving carcinogen-bioactivating CYP-enzyme changes 16,17. Results and Discussion Our study stemmed from the observation that vitamin E treatment of the human non-tumorigenic prostate epithelial RWPE-1 cell line induces the gene expression of P450 enzymes such as CYP1A1 (activating, for example, polychlorinated biphenyls, aromatic amines, PHAs and alkylnitrosamines), CYP1A4 (activating polycyclic