Production of 2,4-diacetylphloroglucinol (2,4-DAPG) and hydrogen cyanide (HCN) by Pseudomonas spp. shows great potential for controlling soilborne plant pathogens. However, little is known about the transcriptional activity of phl and hcn genes encoding 2,4-DAPG and HCN, respectively. To progress toward a better understanding of what triggers phl and hcn expression under rhizosphere conditions, novel PCR primers and TaqMan probes were designed to monitor relative phlD and hcnBC expression in quantitative real time-PCR assays. Transcriptional activity of phlD and hcnBC was studied in time-course confrontational assays using combinations of Pseudomonas spp. isolated in this study: LBUM300 (producing 2,4-DAPG and HCN) and LBUM647 (producing HCN only); pathogens Phytophthora cactorum and Verticillium dahliae; and solid growth media King's B medium and potato dextrose agar. In correlation with the antagonistic activity observed, expression of phlD and hcnBC and production of 2,4-DAPG was detected throughout the 14-day course of the experiment in LBUM300 on both media, while hcnBC expression diminished to undetectable levels in LBUM647. In LBUM300 expression of phlD and hcnBC significantly changed over time and was also influenced by the presence of pathogen and growth media following time-dependent responses.

Climatic elements (solar radiation, daylength, water supply, growing degree days (GDD), corn heat units (CHU), soil, and air temperatures) were monitored to determine which elements could account for the variability in yield of primocane-fruiting red raspberry (Rubus idaeus L.) cultivars. The climatic elements were classed as either having a major or minor influence on the vegetative and reproductive components, based on the frequency of the significance of the multiple regression coefficients. Soil temperature and water supply had a major influence, while daylength, solar radiation, and aboveground temperature (i.e., air, GDD, or CHU) had a lesser influence on these components. Soil temperature had the largest influence during April and May, while water supply was equally influential at all times during the season. Air temperature and solar radiation had their largest influence during the period of flower initiation and development (i.e., June and July), while daylength was most influential from June to October. Berry count, weight, and yield had the highest frequency of associations among the climatic elements, indicating the complexity of the association between these yield components and climate. Total number of nodes/cane, length of the fruiting section/cane, and the harvest period showed the fewest number of associations. Not all cultivars responded similarly to changes in their yield components. `Autumn Bliss' was less sensitive to climatic variation than either `Heritage' or `Redwing'. When `Redwing' was the anomaly, it was usually related to air or soil temperatures.

The insect pool available for carrion visitation and colonisation varies with geographical areas, hence the need to build a comprehensive database wherever such data could be used in forensic investigations. However, most of the geographic records on carrion-related insects are from short-term seasonal studies. Here, we provide the year-round taxonomic composition for the dominant ecosystem of the Maritime lowland ecological region that borders the Gulf of St. Lawrence, Canada, and we examine how this composition is subjected to natural (seasonal) as well as anthropogenic changes. Fresh pig carcasses, used here as human surrogates, were exposed recurrently throughout the whole annual period when carrion-related insects are active in forests and adjacent areas subjected to human-induced land cover changes from agricultural practices. A total of 130 necrophageous and predacious insect species representing 2 orders, 18 families and 75 genera were recovered from carcasses. Abundant fly species were able to visit and/or colonise carcasses exposed in both forests and agricultural fields but the species involved varied throughout the year. Conversely, the complex of abundant coleopterans found on carcasses remained stable throughout the year but differed between forests and agricultural fields. Considering the seasonal and anthropogenic changes that were observed in the complex of carrion-related insects, we stressed that inference on the taxonomic composition in relation to minimum postmortem interval should be restricted to a specific habitat and time of the year. These results also have methodological implications, suggesting that the experimental designs of forensic studies in temperate areas require adjustments to permit robust estimations of minimum postmortem intervals from the insect fauna associated with carcasses.

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The influence of genotype x environment interactions on the performance of `Autumn Bliss' `Heritage' and `Redwing' primocane-fruiting (PF) red raspberry (Rubus idaeus L.) cultivars was studied at six sites across Ontario and Quebec during 1989 and 1990. Cultivar × location × year interactions were found for most vegetative and reproductive components analyzed. `Autumn Bliss' had the most consistent performance of the three cultivars in all location/year combinations, while `Redwing' varied greatly between environments. `Heritage' was always the latest-bearing of the three cultivars and failed to achieve its maximum yield potential in many of the northern locations.