Antipredator behavior of the new mass-reared unisexual strain of the Mexican Fruit Fly

Abstract

Tephritid pests controlled through the sterile insect technique (SIT) are mass-reared and subsequently released in affected areas. Several quality parameters are currently used to test adults, but none take into account interactions with a predator. When sterile males are released in the field, they will need to avoid predators until they reach sexual maturity and survive long enough to mate with wild females. Spiders are one of the most common predators that flies may encounter in release sites. In this study, we evaluated the antipredator behavior of a mass-reared sterile unisexual strain ('Tapachula-7') of the Mexican fruit fly Anastrepha ludens (Diptera: Tephritidae) against their spider predators. We sampled spiders in citrus trees to determine which families could be more common. We established the baseline activity rates of sterile Tapachula-7 (Tap-7) flies in comparison with wild flies. We also tested the behavior of the fertile and sterile bisexual strain and wild flies against hunting spiders (Family Salticidae) and orb building spiders (Family Tetragnathidae). We recorded 18 spider families, with Salticidae being the most dominant. Tap-7 flies diminished their activity in comparison with wild males at 1800 h but showed similar activity levels earlier in the day. When exposed to orb-web spiders (Leucauge venusta), Tap-7, fertile and sterile males from the bisexual strain had similar rates of survival, but Tap-7 males showed lower survival than wild males. Against hunting spiders (Phidippus audax), wild males had higher probability of defensive wing displays, but there was no difference in spider attack rates. In general, sterile Tap -7 males performed as well as males from the bisexual strain, although they had lower survival than wild males. This could be due to either mass-rearing and/or irradiation effects. We recommend the use of the defensive wing display behavior as a quality parameter and propose a rapid and effective method to evaluate fly activity. The efficiency of SIT will be improved if released sterile males have the same antipredator repertoire as their wild counterparts.

Effect of natural predators on Queensland fruit fly, Bactrocera tryoni (Froggatt) (Diptera: Tephritidae) control by sterile insect technique (SIT)

“…Studies that used wild and domesticated fruit flies found that irradiation and mass‐rearing greatly affect sterile fly survival against predators. For example, González‐López et al ., Rao et al . and Dor et al .…”

“…Studies that used wild and domesticated fruit flies found that irradiation and mass-rearing greatly affect sterile fly survival against predators. For example, González-López et al, 54 Rao et al 55 and Dor et al 56 found that the survival of sterile Mexican fruit fly (Anastrepha ludens) males against their predators is very low compared with their wild counterparts. Similarly, studies on Mediterranean fruit fly showed that sterile males are less likely to evade capture by their predators than wild flies.…”

Timing of Irradiation and Male Mating History Effects on Female Remating inAnastrepha ludens(Diptera: Tephritidae)

“…The time to sexual maturity, compatibility with wild flies, and mating competitiveness of this strain is comparable to the bisexual strain (Orozco et al 2013), although Tap-7 males have a different chemical pheromone composition than the bisexual strain (Bosa et al 2016). Also, recent studies found lower emergence, lower amount of fliers, and shorter longevity under irradiation for the Tap-7 strain (Arredondo et al 2016), but comparable anti-predator response, dispersal, and field survival compared with the bisexual strain (Flores et al 2015;González-López et al 2016). Compared with the bisexual strain, Tap-7 males have lower fertility due to their chromosomal arrangement (Zepeda-Cisneros et al 2014).…”

Survival ability of Mexican fruit fly males from different strains in presence of the predatory orb-weaving spider Argiope argentata (Araneae: Araneidae)

“…González-López et al , (2016) found 18 families of spiders in Mexican citrus orchards where the Mexican fruit fly was common. The most abundant spider families were Salticidae, Anyphaenidae and Thomisidae.…”

“…The most abundant spider families were Salticidae, Anyphaenidae and Thomisidae. In semi-field conditions, sterile males of the unisexual strain of A. ludens (Tapachula-7) (Zepeda-Cisneros et al , 2014) showed a lower survival than fertile wild males in the presence of the orb-web spider Leucauge venusta (Araneae: Tetragnathidae) (González-López et al , 2016).…”