Splash dispersal of Pseudocercosporella capsellae, cause of white leaf spot on oilseed rape

Non peer reviewe

Effects of rainfall intensity and duration on dispersal of Rhynchosporium secalis conidia from infected barley leaves

Simulated rain of two intensities was allowed to fall for 30 min on to barley leaves infected by Rhynchosporium secalis. The resulting splash droplets were collected on horizontal pieces of fixed photographic film. Most spore-carrying droplets were in the 400–800 μm diam range. They were dispersed as far as 1 m from the barley leaves and the number of conidia collected on horizontal microscope slides declined exponentially with distance from the leaves. It was estimated that, of the conidia dispersed in 30 min of simulated rainfall with an intensity of 12 mm h−1, 40% were dispersed in the first 10 min and 27% in the last 10 min, and with an intensity of 65 mm h−1 39% were dispersed in the first 10 min and 25% in the last 10 min. Horizontal pieces of film and microscope slides were placed, under rain-shields, at 15 cm above ground level in an infected crop of winter barley during June and July 1985. Of the spore-carrying droplets collected during periods of rain, most were less than 400 μm diam, but most spores were in 400–800 μm diam droplets. No conidia were collected during dry weather or during rainfall with intensity less than 0.2 mm h−1. During showers most conidia were collected when rainfall intensity was greatest; a regression of number of conidia collected cm−2 min−1 on rainfall intensity (both square-root transformed) accounted for 76% of the variance.Peer reviewe

Identifying best practice, installation, laboratory testing, and field testing

This paper summarizes recommendations for best practice associated with the installation of geothermal loops within foundations to form thermopiles, based on experience gained over the past 10 years in the UK. The issue of paramount importance in constructing a successful thermopile installation is the early stage coordination with all parties that will encounter, install or test the geothermal loops. Several lessons learned from the installation and construction of thermopiles are described to help ensure a smooth installation process. As long as there is early coordination, the installation of geothermal heat exchange tubing is relatively simple and will have very little or no impact on typical deep foundation installation procedures. This, coupled with the fact that there are additional costs and implications associated with other geothermal heat exchange approaches, implies that thermopiles are an ideal economic solution to access a renewable energy source