No abstract

The potential impact of postdispersal seed predation by the field cricket, Teleogryllus emma (Ohmachi et Matsuura), on the seedling emergence of Italian ryegrass (Lolium multiflorum Lam.), a non-native grass weed in Japan, was determined. The relationship between cricket density and the proportion of seedling emergence was investigated by conducting manipulative experiments in duplicate, using enclosures. One-thousand seeds of Italian ryegrass were exposed to adult crickets at different densities (zero, one, two, four and eight individuals per 2.25 m 2 enclosure) for 2 weeks.The proportion of seedling emergence decreased with increasing cricket density. The proportion of seedling emergence in the enclosures without the crickets was 90.9-97.2%, whereas the seedling emergence in the enclosures with eight crickets greatly decreased, to 0.5-2.5%. These results suggest that postdispersal seed predation by T. emma can substantially decrease the abundance of Italian ryegrass at an early life stage and reduce its population in environments with a high density of crickets.

No abstract

Novel apatite-based photocatalyst (TiHAP) films have been prepared by wet process. The films have high transparency with little infringing color. SEM, XPS, and UV–vis analyses were carried out, and it was revealed that the obtained films were similar to TiHAP powder. The films showed photocatalytic activity against adsorbed Methylene Blue and gaseous isopropyl alcohol and no photoinduced hydrophilicity.

Mowing weeds in rice paddy field ridges is essential for weed management. However, excessive mowing causes the dominance of the Poaceae weeds, which are host plants for rice stink bugs. In this study, the authors hypothesized that high mowing is more effective than low mowing in decreasing the dominance of Poaceae weeds. The dominance of the Poaceae weeds between high mowing (cut at a height of 5-10 cm) and low mowing (cut at ground level) was compared across 5 sites. As a result, the cover-abundance ratings of the Poaceae weeds were lower in the high mowing plots than that in the low mowing plots in all sites. In addition, the biodiversity index was higher in the high mowing plots than in the low mowing plots in each site. It was concluded that the increased mowing height effectively decreased the dominance of Poaceae weeds and this can be used as a strategy for controlling rice stink bugs.