CALIFORNIA AGRICULTURE Progress Reports of Agricultural Research published monthly by the University of Cali: fornia Division of Agricultural Sciences. William W. Paul . . . . . . . . . . . . . .Manager Agricultural Publications Jer ry Lester . . . . . . . . . . . . . . . . . . . .Editor Eleanore Browning . . . . . .Assistant Editor California Agriculture Articles published herein may be republ...

Abstract Supplemental food from anthropogenic sources is a source of conflict with humans for many wildlife species. Food-seeking behaviours by black bears Ursus americanus and brown arctos can lead to property damage, human injury mortality the offending bears. Such conflicts are well-known conservation management issue wherever people live in bear habitats. In contrast, use foods polar mariti...

Olfaction is a versatile and sensitive mechanism for detecting volatile odorants. We show that the nematode C. elegans detects many volatile chemicals, which can be attractants, repellents, or attractants at low concentrations and repellents at high concentrations. Through laser ablation, we have identified chemosensory neurons that detect volatile odorants. Chemotaxis to volatile odorants requ...

Phenotypic analysis of the daf-11 and daf-21 mutants of Caenorhabditis elegans suggests that they have defects in components shared by processes analogous to vertebrate taste and olfaction. daf-11 and daf-21 mutations were previously shown to cause inappropriate response to the dauer-inducing pheromone. By mutational analysis and by disabling specific chemosensory sensilla with a laser, we show...

Intracellular recordings show that (i) paramecia hyperpolarize slightly in attractants and depolarize in repellents that depend on the avoiding reaction (an abrupt change of swimming direction), and (ii) paramecia more strongly hyperpolarize in repellents and more strongly depolarize in attractants that depend on changes of swimming velocity. These membrane potential changes are in agreement wi...

The relative attractiveness of six commercially available protein hydrolysates and the influence of their concentration were evaluated in field cages by a release-capture method of lab-reared melon fly adults, Bactrocera cucurbitae (Coquillett). Buminal, Corn Steepwater, Hym-Lure, Pinnacle, Nulure, and SolBait were tested for both sexes of the melon fly. The tested products exhibited clear diff...