From laboratory to the field: biological control of Fusarium graminearum on infected maize crop residues.

AIM: To evaluate biological control agents (BCAs) against Fusarium graminearum on infected maize stalks as a means to reduce Fusarium head blight (FHB) in subsequently grown wheat. METHODS AND RESULTS: In the laboratory, BCAs were applied against F. graminearum on maize stalk pieces. Clonostachys rosea inhibited the perithecia development and ascospore discharge when applied before, simultaneously with and after the pathogen. In the field, we simulated a system with high disease pressure, that is, a maize-wheat rotation under no-tillage, by preparing maize stalks inoculated with F. graminearum. The infected stalks were treated with formulations of C. rosea selected in vitro or the commercial BCA strain Trichoderma atrobrunneum ITEM908 and exposed to field conditions over winter and spring between winter wheat rows. Monitoring with spore traps and of FHB symptoms, as well as quantification of F. graminearum incidence and DNA in harvested grain revealed significant reductions by C. rosea by up to 85, 91, 69 and 95% compared with an inoculated but untreated positive control, respectively. Deoxynivalenol (DON) and zearalenone (ZEN) contents were reduced by up to 93 and 98%, respectively. Treatments with T. atrobrunneum were inconsistent, with significant reductions of DON and ZEN under warm and wet climatic conditions only. CONCLUSIONS: The findings support the application of C. rosea against F. graminearum on residues of maize to suppress the primary inoculum of FHB. SIGNIFICANCE AND IMPACT OF THE STUDY: As sustainable agriculture requires solutions to control FHB, hence, the application of C. rosea during the mulching of maize crop residues should be evaluated in on-farm experiments.

A mathematical equation for quantifying control functionality in agricultural tractors.

The overall accessibility of controls is one of the most important issues to consider when designing a control layout. Well-arranged controls, whose operational characteristics are based on both design guidelines and on human factors considerations, allow the operator to efficiently interact with the system in question. The objective of this article is to introduce a numerical index, referred to as the "index of functionality", capable of comparing, on a mathematical basis, different control arrangements in agricultural tractors. The model is based on information that has been gleaned from the published literature, with input from both professional ergonomists and experienced agricultural tractor operators. The numerical index may take any value between 0 and +1, with +1 being defined as an optimum value in terms of the functionality of a workstation. Data were collected from six old (pre-1982) and six modern (post-2003) tractor workstations to determine whether the model would recognize improvements that have occurred in the ergonomic design of tractor control layouts over the past 20 years. An average score of 0.19 +/- 0.07 was calculated for the pre-1982 tractor workstations. By contrast, an average score of 0.63 +/- 0.10 was calculated for the post-2003 tractor workstations. A number of limitations have been identified with the current model; despite these limitations, the index of functionality clearly recognized the ergonomic improvements in tractor workstations that have occurred over the past 20 years.

Cadmium-induced hepatotoxicity in three different rat strains.

Cadmium (Cd) is a highly toxic element able to induce acute liver injury in rats after intraperitoneal administration. The dose-dependent Cd-induced hepatotoxicity was examined in three different rat strains. A difference in hepatotoxicity was observed in the three rat strains, determined by the examination of serum enzymes' activities and other biochemical parameters, all markedly altered after Cd intoxication. The histological findings came to confirm the variations of the above-mentioned parameters. It is concluded that the administration of this toxic agent caused different toxicity in the three rat strains examined, indicating a more intense damage in Wistar than in Quinster and Lewis rats.