Characterization of genetic identities and relationships of Brassica oleracea L. via a random amplified polymorphic DNA assay

Summary Effective conservation and the use of plant genetic resources are essential for future agricultural progress. Critical to this conservation effort is the development of genetic markers which not only distinguish individuals and accessions but also reflect the inherent variation and genetic relationships among collection holdings. We have examined the applicability of the random amplified polymorphic DNA (RAPD) assay for quick, cost-effective, and reliable use in addressing these needs in relation to collection organization and management. Twenty-five decamer oligonucleotide primers were screened individually with a test array composed of individuals representing a range of genetic relationships in Brassica oleracea L. (vegetable and forage cole crops). Over 140 reproducible, polymorphic fragments were generated for study. Each individual of the test array exhibited a unique molecular genotype and composites specific for accessions and botanical varieties could be established. An analysis of similarity based on amplified DNA fragments reflected the known genetic relationships among the selected entries. These results demonstrated that RAPD markers can be of great value in gene bank management for purposes of identification, measurement of variation, and establishment of genetic similarity at the intraspecific level.     

Thyreophoran vertebrae from the Callovian (Middle Jurassic) of the Vaches Noires cliffs (Normandy,France), with remarks on the dinosaur assemblage from the Vaches Noires

Two associated incomplete thyreophoran dorsal vertebrae from the Callovian Marnes de Dives Formation of the Vaches Noires cliffs, on the Normandy coast, are referred to an indeterminate stegosaur that appears to be different from Lexovisaurus, previously reported from the Callovian of western France. These vertebrae are the first evidence of thyreophorans from the Vaches Noires and complement the dinosaur assemblage from this locality, which hitherto consisted of several theropod taxa and an indeterminate sauropod. The dinosaur record from the Vaches Noires is heavily dominated by theropods and this imbalance is difficult to explain. A possible explanation may be that the dinosaur sample from the Vaches Noires is too small to be statistically significant and representative of the original faunal assemblage from which it is derived.     

Claude Bourgelat and the creation of the first veterinary schools

The first veterinary school in the world was created in Lyon in 1761 by an equerry, Claude Bourgelat (1712-1779), a man renowned for his skill in horsemanship and horse medicine, a man fully able to understand the issues of his time. Aware of the scope of the physiocratic movement and of the need to improve the health of farm animals, he was able to understand the expectations of Henri-Léonard Bertin, Minister of King Louis XV, in proposing the creation of an establishment, breaking with traditional farriery. The creation of the Veterinary School of Lyon would mark a milestone: the consideration of livestock and the establishment of a profession, based on a scientific approach applied to all species. His relations, his communication skills, his European reputation and the opening of the first two schools to foreign students have ensured dissemination of this renewed vision throughout Europe, and provided these schools and their creator with a reputation that they still retain today.     

Chemical speciation of cadmium and lead and their bioavailability to cole (Brassica campestris L.) from multi-metals contaminated soil in northwestern China

A pot experiment was conducted to study the relationship between speciation distribution of cadmium (Cd) and lead (Pb) and their availability to cole (Brassica campestris L.) grown on the Cd–Pb polluted soil in northwest of China. The results showed that Cd in the unpolluted soil was mainly bound to carbonate fraction (F2) and Fe–Mn oxide fraction (F3), and Pb was mainly bound to carbonate fraction (F2) and residual fraction (F5). However, marked change of Cd and Pb fractionation was observed with increasing soil Cd and Pb concentrations, where the concentrations of Cd in F1 (exchangeable fraction), F2 and F3 increased significantly (p < 0.001 for F1, F2 and F3), and Pb in F1, F2, F3 and F4 increased significantly (p < 0.001 for F1, F2, F3 and F4).The correlation analysis between the fraction distribution coefficient of Cd and Pb in the soil and Cd and Pb concentration accumulated in cole showed that both Cd and Pb in F1 fraction in the soil made the greatest contribution on the accumulation of Cd and Pb in cole. Higher bio-concentration factors (BCFs) and translocation factors (TFs) for Cd and lower BCFs and TFs for Pb were observed in the cole, respectively. Cd had higher accumulation in the edible parts of the cole, but Pb had lower accumulation in that. Therefore, Cd has higher risk to human health than Pb when people eat the coles grown in Cd–Pb polluted soil in northwestern China.     

Evidence for behavioural resistance by the diamondback moth, Plutella xylostella (L.)

Abstract:  The diamondback moth (DBM), Plutella xylostella (L.) (Lep., Plutellidae), is an important pest of brassicaceous crops worldwide. It has developed resistance to almost every synthetic insecticide applied in the field and consequently is often difficult to control in crucifer-growing areas. DBM oviposition behaviour was investigated in greenhouse and growth chamber conditions with seven cruciferous and one non-cruciferous plant varieties. In free choice tests, females deposited more eggs on the stem near the soil-stem interface than on leaves. Our findings suggest that DBM is capable of developing behavioural resistance through oviposition site selection to avoid lethal doses of foliar-applied insecticides in the field.     

From the creation of the Veterinary Schools to the evolution of the notion of contagion in the 19th and 20th centuries

The creation of the Veterinary Schools in the 18th century would reveal a plethora of scientists, some of whom would be the precursors of Pasteur, some rivals, others followers collaborators or friends of the Master. Among the precursors let us name Chabbert, Huzard, Girard, Delafond, Renault, Toussaint, Galtier ; among the rivals: Chauveau, Arloing, Cornevin and Thomas; among the followers, collaborators or friends of Pasteur: Bouley, at first a resolute spontaneist, then the most fervent in defense of Pasteur (President of the Academy of Medicine and of the Academy of Sciences) and Nocard, Director of the School in Alfort, an important collaborator of Pasteur. Later, there was Leclainche, who created the International Office of Epizootics, and who was President of the Academy of Sciences; Guérin, who with Calmette developed the BCG vaccination; Ramon, the father of anatoxins (vaccines against diphtheria, and tetanus, combined vaccines, adjuvants to immunity). Thus, the creation of the Veterinary Schools contributed not only to the evolution of the notion of contagion, to the amelioration of animal health and the economics of agricultural production, but also to serious advances in human care, and to the protection of public health.     

Pathogenicity of Heterorhabditis nematodes isolated from north-western Himalaya against the larvae of Plutella xylostella (L.) (Lepidoptera: Plutellidae)

The efficacy of three entomopathogenic nematodes (Heterorhabditis spp.), from north western Himalaya, India was studied against the diamondback moth, Plutella xylostella (Linnaeus, 1758) (Lepidoptera: Plutellidae), under laboratory conditions. The larvae were exposed to 10, 20, 30 and 40 infective juveniles (IJs) of each nematode species for different time periods and they were found to be susceptible to all the EPNs tested. However, the susceptibility of larvae to nematode infection varied according to the dosages of IJs and their exposure periods. The efficacy of these indigenous entomopathogenic nematodes was also evaluated against the commercially available entomopathogenic nematode H. indica. An indigenous isolate, H. bacteriophora (HRJ), along with the commercial isolate H. indica recorded 100.0% mortality of insect larvae in 96 h exposure time against third instar larvae of P. xylostella. However, it was noticed that with the advancement of larval stage its mortality rate reduces and vice versa with the exposure period. All the tested nematode species were also found to reproduce within the host and produced infective juveniles. In conclusion, the evidence obtained in this study suggests that all the three indigenous EPN species are virulent enough to produce 100% mortality of larvae of P. xylostella. These EPN species thus have potential for the management of P. xylostella under integrated management practices.