ABSTRACT
The sugarcane hairy borer, Hyponeuma taltula (Schaus, 1904), attacks the base of sugarcane and causes the death of the apical bud, a symptom known as "dead heart." In recent years, there has been significant infestation in Brazilian sugarcane crops. With the purpose of finding methods for controlling and/or monitoring the pest for the sustainable cultivation of sugarcane, we characterized the mating behavior of H. taltula and confirmed the release of a sex pheromone by this insect. Sexual activity was observed between the second and ninth hour of scotophase, during which female calling caused the onset of male courtship behaviors and increased their frequency. An ethogram was built showing that males perform seven observable steps: (1) wing flapping, (2) walking with wing flapping, (3) flying, (4) flying towards the female, (5) landing near the female and walking around her, (6) attempting copulation, and (7) copulation (mating). Female sex gland extracts also triggered attraction and male courtship behaviors. These results thus confirm that the female abdominal gland produces a sex pheromone and that the presence of this pheromone in the air is needed to initiate the male courtship sequence. The sexual behavior of H. taltula is compatible with control and/or monitoring methods using female sex pheromones.
Subject(s)
Moths/physiology , Saccharum , Sex Attractants/physiology , Sexual Behavior, Animal , Animals , Brazil , FemaleABSTRACT
The stable fly, Stomoxys calcitrans (Diptera: Muscidae), is a worldwide pest of livestock. Recent outbreaks of stable flies in sugarcane fields in Brazil have become a serious problem for livestock producers. Larvae and pupae found inside sugarcane stems after harvesting may indicate that stable flies use these stems as potential oviposition or larval development sites. Field observations suggest that outbreaks of stable flies are associated with the vinasse and filter cake derived from biomass distillation in sugarcane ethanol production that are used as fertilizers in sugarcane fields. Adult stable flies are attracted to vinasse, which appears to present an ideal larval development site. The primary goal of the present study is to demonstrate the role of vinasse in influencing the sensory physiological and behavioural responses of stable flies, and to identify its associated volatile attractant compounds. Both laboratory and field studies showed that vinasse is extremely attractive to adult stable flies. Chemical analyses of volatiles collected revealed a wide range of carboxylic acids, alcohols, phenols and aldehydes as potential attractant compounds. These newly identified attractants could be used to develop a tool for the attractant-baited mass trapping of stable flies in order to reduce infestations.
