Repellent and Oviposition-Deterring Effects of Hop Beta-Acids on the Two-Spotted Spider Mite Tetranychus urticae

Colupulone, the main component of the beta-acid fraction of hop extracts, was shown to repel the two-spotted spider mite Tetranychus urticae Koch from the surface of plant leaves. The total beta-acid fraction was found more effective in repelling the mites and reducing the number of eggs laid than colupulone at equivalent concentrations, suggesting that other components of the extract have repellent and oviposition-deterring effects.     

Monitoring the Exposure of Barn Owls to Second-Generation Rodenticides in Southern Eire

In an extensive field study conducted over five counties in southern Eire during the winter of 1988–89, 19 Barn Owl (Tyto alba) roosts and/or nests were located. The local farmers and landowners within about a one-mile radius of the Barn Owl sites were surveyed concerning their use of rodenticides and observations of any secondary rodenticide toxicity effects. Regurgitated owl pellets were collected: (a) for dissection and prey analysis, and (b) for chemical analysis to determine residues of the second-generation rodenticides, brodifacoum, difenacoum and flocoumafen. Most farmers interviewed used rodenticide baits (73%), and almost all (92%) stated that they took precautions to protect domestic and wild non-target animals. The four rodent species, brown rat, wood mouse, house mouse and bank vole provided 83% of the Barn Owl diet, and birds contributed another 12%. At least 97% of the 89 pellets analysed contained less than the limit of determination of the three second-generation rodenticides, 0·01–0·02 mg kg⁻¹ of each isomer. Apparent residues in the remainder were likely to be the result of interference from co-extracted material. These results indicated that during the monitoring period, none of the owls studied was exposed to significant residues of these rodenticides in their prey.     

The Effect on Soil Fertility of Repeated Applications of Pesticides over 20 Years

Concern has been expressed that repeated use of pesticides may be leading to accumulation of residues in soil and to damaging effects on the environment. A long-term experiment, known as the Chemical Reference Plots, was started in 1974 on a silty clay loam soil at Rothamsted in which plots received applications of up to five pesticides (aldicarb, benomyl, chlorfenvinphos, glyphosate and chlorotoluron or triadimefon), each plot receiving the same treatment annually for up to 20 years. Spring barley was grown each year, and its yield was taken as an indicator of soil fertility. The glyphosate and triadimefon were applied to the autumn stubble prior to ploughing from growing seasons 1980 and 1982 respectively, chlorotoluron was sprayed pre-emergence (1974 and 1976 only) and the other compounds were incorporated into the soil in spring immediately before sowing (1974–1993 inclusive). No deleterious effects on crop productivity were observed from these pesticide applications, and no differences could be found in microbial processes in soils sampled in April 1992 save for a small increase in the amount of microbial-biomass carbon in plots receiving aldicarb. No pesticide residues could be detected in soil taken in August 1994, 17 months after the last experimental treatment. In laboratory incubations using these same soil samples, the degradation of aldicarb residues was greatly enhanced in plots that had received aldicarb for 20 years, whereas degradation rates of benomyl, chlorfenvinphos and triadimefon residues were not influenced by the treatment history.     

Spatial and seasonal differences in the top predators of Easter Island: Essential data for implementing the new Rapa Nui multiple‐uses marine protected area

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Impact of Long-term Training and Extension Support on Small-scale Carp Polyculture Farms of Bangladesh

One of the unique features of the Development of Sustainable Aquaculture Project of the WorldFish Center, Bangladesh, was the provision of 3 y of continuous training and extension in support of the fish farmers involved. It was expected that the long-term support would make a significant contribution to boosting production and incomes as well as sustainability. The article demonstrates the impact of the training and extension support to small-scale carp polyculture farmers in terms of productivity, profitability, and efficiency. The study used data collected from 225 project farmers and 123 control farmers during 2002/2003 to 2005/2006. The results show that the project farmers achieved an average growth rate in productivity terms (kg/ha) of about 23% per annum compared with only 3.8% among control farmers. Estimated annual return on investment per demonstration farm exhibits 52% higher return over the 3-y intervention period. During 2002/2003 to 2005/2006, the average technical efficiency score of project farmers increased from 0.55 to 0.86 compared with an average increase from 0.67 to 0.78 among control farmers over the same time period. The results showed that the efficiency gains and resulting increased productivity came from the development of human capital through long-term efficient and effective training and extension support.     

An Improved Procedure for EI Nino Forecasting: Implications for Predictability

A coupled ocean-atmosphere data assimilation procedure yields improved forecasts of El Ni?o for the 1980s compared with previous forecasting procedures. As in earlier forecasts with the same model, no oceanic data were used, and only wind information was assimilated. The improvement is attributed to the explicit consideration of air-sea interaction in the initialization. These results suggest that EI Ni?o is more predictable than previously estimated, but that predictability may vary on decadal or longer time scales. This procedure also eliminates the well-known spring barrier to EI Ni?o prediction, which implies that it may not be intrinsic to the real climate system.     

Variations in the profile and content of anthocyanins in wines made from cabernet sauvignon and hybrid grapes

To detect adulteration of wine, it has been proposed that the ratio of acetylated to p-coumaroylated conjugates of nine characteristic anthocyanins can be used to determine whether a wine is derived from Cabernet Sauvignon or hybrid grapes. If the ratio is >3, then a wine is classified as being derived from Cabernet Sauvignon grapes. This test has significant commercial implications as it is being used to decide whether Cabernet Sauvignon-labeled wines are genuine and can be imported into Germany. To assess whether this is a valid approach, 24 wines were analyzed, 4 of which were made from hybrids and 20 from Cabernet Sauvignon, with vintages ranging from 1993 to 2000. Only 13 of the Cabernet Sauvignon wines contained all nine of the "characteristic" anthocyanins, and the ratio of acetylated to p-coumaroylated derivatives varied from 1.2 to 6.5. It is evident that the use of the anthocyanin ratio method is flawed and that examination of the whole anthocyanin profile and/or investigation of the proportion of monoglucoside and acetylated anthocyanins is a better approach to distinguish between hybrid and Cabernet Sauvignon wines.     

From flat foot to fat foot: structure, ontogeny, function, and evolution of elephant "sixth toes"

Several groups of tetrapods have expanded sesamoid (small, tendon-anchoring) bones into digit-like structures ("predigits"), such as pandas' "thumbs." Elephants similarly have expanded structures in the fat pads of their fore- and hindfeet, but for three centuries these have been overlooked as mere cartilaginous curiosities. We show that these are indeed massive sesamoids that employ a patchy mode of ossification of a massive cartilaginous precursor and that the predigits act functionally like digits. Further, we reveal clear osteological correlates of predigit joint articulation with the carpals/tarsals that are visible in fossils. Our survey shows that basal proboscideans were relatively "flat-footed" (plantigrade), whereas early elephantiforms evolved the more derived "tip-toed" (subunguligrade) morphology, including the predigits and fat pad, of extant elephants. Thus, elephants co-opted sesamoid bones into a role as false digits and used them for support as they changed their foot posture.     

Can crop science really help us to produce more better-quality food while reducing the world-wide environmental footprint of agriculture?

This paper reviews recent developments in crop science that can be the basis of a revolution in the global food system but it is also emphasized that such a revolution requires more than changes in food production and supply. We must more effectively feed a growing global population with a healthy diet while also defining and delivering the kinds of sustainable food systems that will minimise damage to our planet. There are exciting new developments in crop production biology but much existing crop science can be exploited to increase yields with the aid of a knowledge exchange (KE) framework requiring the use of new technology now available to most people across the globe. We discuss novel approaches at both the plant and the crop level that will enhance nutrient and water productivity and we also outline ways in which energy use and greenhouse gas (GHG) emissions can be reduced and labor shortages combatted. Exploitation of new biology and new engineering opportunities will require development of public-private partnerships and collaborations across the disciplines to allow us to move effectively from discovery science to practical application. It is also important that consumers contribute to the debate over proposed changes to food and farming and so effective KE mechanisms are required between all relevant communities.