In moth sex pheromone olfaction systems, there is a stereotypical co-compartmentalization of two or sometimes three olfactory receptor neurons (ORNs) within single trichoid sensilla on which pheromone-sensitive odorant receptors (ORs) are differentially expressed. In this issue of Chemical Senses, Krieger et al. show through elegant double and triple in situ hybridization studies that in the mo...

Hesperomyces virescens Thaxter (Laboulbeniales: Laboulbeniaceae) is a parasitic fungus that infects lady beetles (Coleoptera: Coccinellidae) via horizontal transmission between adults at overwintering and feeding sites. The differential behavior of male and female hosts could have profound effects on intensity of infection and positioning of fungus on the host's integument. The influence of hos...

Effective biological control of destructive heliothine larvae via application of microbial entomopathogens or parasitoids is limited by a robust immune response against infection and parasitization. To better understand the immune response of budworms against microbial entomopathogens, several orthologs of antibacterial response proteins were identified and extracted from a tobacco budworm, Hel...

Infections can have detrimental effects on the fitness of an animal. Reproducing females may therefore be sensitive to cues of infection and be able to adaptively change their oviposition strategy in the face of infection. As one possibility, females could make a terminal investment and shift reproductive effort from future to current reproduction as life expectancy decreases. We hypothesized t...

Binding of the Bacillus thuringiensis Cry1Ac toxin to specific receptors in the midgut brush border membrane is required for toxicity. Alteration of these receptors is the most reported mechanism of resistance. We used a proteomic approach to identify Cry1Ac binding proteins from intestinal brush border membrane (BBM) prepared from Heliothis virescens larvae. Cry1Ac binding BBM proteins were de...

The lepidopteran-specific, insecticidal crystal proteins of Bacillus thuringiensis vary in toxicity to different species of lepidopteran larvae. We report studies of CryIA(a) and CryIA(c), two related proteins that have different degrees of toxicity to Heliothis virescens yet very similar degrees of toxicity to Manduca sexta. The amino acid differences between these proteins are located primari...

Sterile backcross (Be) males originate from the hybridization of Heliothis subflexa (Guennee) females to H. virescens (F.) males followed by recurrent backcrossing of the fertile female progeny to H. virescens males. Ultrastructural transmission electron microscope (TEM) studies of the postmeiotic maturation of eupyrene sperm cells in Be males, and comparisons with the cells in normal H. viresc...

Two unusual greenswards occurring on Pu'u 'Alaea in 1989 reportedly possessed vegetative features characteristic of the presumed extirpated species Argyroxiphium virescens Hillebr. One of these Pu'u 'Alaea plants flowered in August 1989, allowing detailed comparisons with preserved specimens of A. virescens as well as other species and hybrids of Argyroxiphium native to East Maui. These compari...

Resistance management for Bt-transgenic crops relies in part on the production of sufficient numbers of susceptible insects in non-toxic refuges. Simulation models suggested that source-sink dynamics could interact with the structure of refuges to impact the production of insects in these areas. We tested the hypothesis that altering isolation between refuges and transgenic cotton by manipulati...