Literature review of chalkbrood a fungal disease of honeybees

Quantified amounts of Ascosphaera apis spores, causative organism ofchalkbrood disease, were cultured in vitro after being treated withtricloroisocianuric acid (TCA) (Yukoluck 93% a.i) inside honeybee colonies.This gaseous substance is registered in several countries for the control ofchalkbrood, a invasive mycosis affecting honeybee larvae. TCA acts, on thespores that are present inside the hive. The product was applied at therecommended dose (3 g/80 ml/hive) and the spore inocula were kept inside acommercial hive treated with TCA for 48 h before being cultured in vitro.Results show that efficacy of TCA is strongly linked with two main factors:Amount of spores and the degree of agglutination in sporeballs. TI:Field assays for hygienic behaviour in honey bees (Hymenoptera: Apidae).AU:Spivak-M; Downey-DLAD:Department of Entomology, 219 Hodson Hall, University of Minnesota, St.Paul, MN 55108, USA.SO:Journal-of-Economic-Entomology. 1998, 91: 1, 64-70; 24 ref.PY:1998LA:EnglishAB:Honey bee (Apis mellifera) hygienic behaviour is a mechanism of diseaseresistance and a mode of defence against the parasitic mite Varroa jacobsoni.Hygienic bees uncap and remove diseased and parasitized brood from the nest.The propagation of colonies that demonstrate resistance to chalkbrood andAmerican foulbrood and that remove pupae infested by Varroa mites isbecoming increasingly important in apiculture. This study evaluates 2 commonlyused field assays used to screen colonies for hygienic behaviour: the freeze-killed brood and the pierced brood assays. Both involve determining the timerequired for worker bees to remove dead capped brood from a section of comb.Colonies in the experiment displayed a wide range of removal rates and weregrouped as hygienic, nonhygienic or intermediate. The results of experiments 1and 2 indicated that neither the age nor the source of the frozen brood had asignificant effect on the removal rate by hygienic colonies (i.e. those coloniesthat consistently uncapped and removed freeze-killed brood with 48 h). In