Habitat factors associated with Fopius caudatus parasitism and population level of its host, Ceratitis cosyra

Abstract

Biotic and abiotic factors affect herbivores and their natural enemies and understanding of their requirements may permit habitat modification enabling conservation biological control. Ceratitis cosyra Walker (Diptera: Tephritidae), an African-native fruit fly pest is mostly parasitized by the parasitoid wasp Fopius caudatus Sz epligeti (Hymenoptera: Braconidae). To assess F. caudatus habitat, the wasp parasitism levels and infestation of its fruit fly host were examined in Sarcocephalus latifolius (Smith) Bruce (Rubiaceae), a shrub of which the fruits are among the preferred hosts of C. cosyra and F. caudatus. Fruit-collection site descriptions, including plant species presence, were analysed in relation to the target insect abundances (emergence from target fruit). Ceratitis cosyra and F. caudatus emerged from all sites; nonetheless, their population levels were associated with both abiotic and biotic factors, of which some can be manipulated. Several factors, such as cultivation level, topography, and vegetation coverage, were correlated with F. caudatus parasitism. Ceratitis cosyra infestation level was correlated with factors such as density of S. latifolius, vegetation cover, cultivation practices, temperature, altitude, rainfall pattern, and stoniness. Proximity to other fruit fly host plants correlated with both pest abundance and F. caudatus parasitism level of the fruit fly. The findings that insects' interactions and abundance are influenced by habitat structure and that parasitism is positively related to natural habitat indicates the importance of maintaining natural habitats in closeness to cultivated areas with the aim of enhancing pest suppression by parasitoids. Further studies should attempt to identify how plant species composition in and around orchards could affect the management of tephritid fruit fly pests.

Differential responses of Bactrocera dorsalis and its parasitoids to headspaces of different varieties of tree-attached mango fruits and the associated chemical profiles

“…Similar observations were made by Altuzar et al (2004). This indicates that the olfactory tuning of F. arisanus, and likely many other parasitoids, utilize volatiles emitted by the host of their host, i.e., environmental cues that enhance finding suitable tephritid hosts (Nanga Nanga et al, 2019;Mama Sambo et al, 2020;Ayelo et al, 2021). The attraction of D. longicaudata to volatiles of B. dorsalis infested Apple and Haden mangoes, at both day 7 and 9 postoviposited mango volatiles and not to volatiles of B. dorsalisinfested Kent mango signifies that the fruits with developing larvae produce attractive volatiles compared to those that do not have.…”

Identification, Microhabitat, and Ecological Niche Prediction of Two Promising Native Parasitoids of Tuta absoluta in Kenya

“…The geographical coordinates and altitude were recorded for each farm, where samples were collected, using the Global Positioning System (GPS). The percent parasitism of each parasitoid species on the associated host, T. absoluta , was estimated as (the number of parasitoids emerging divided by the total number of T. absoluta and the parasitoids from a sample) × 100 [ 44 , 48 ], while the level of T. absoluta infestation was recorded as the sum of the number of T. absoluta recovered from a sample and the number of recovered parasitoids.…”

“…The tomato production system was also recorded as either an open field or greenhouse/screen house production. Additionally, an average number of N. tenuis per kilogram of tomato leaves were estimated and four classes were obtained for this variable 0 = absence of N. tenuis , [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 ] = low-level presence of N. tenuis , [ 50 ,…”

“…Furthermore, habitat and climate are significant factors limiting the distribution and abundance of insect pests, as well as their physiology and reproduction [ 37 , 38 , 39 , 40 , 41 , 42 ]. Parasitoids and predator distribution on a local scale, are also affected by agronomic practices such as pesticide application [ 43 , 44 ]. It is against this background that the current study sought to assess the presence and distribution of parasitoid species in open-field and greenhouse tomatoes in Kenya and their effectiveness in controlling T. absoluta as well as to determine their suitable habitat for perseverance in biological control programs.…”

Native Hymenopteran parasitoids associated with fruit flies (Diptera: Tephritidae) in fruits and vegetables in three ecological zones of Togo

“…The identification of fruit flies was conducted using the reference works for Africa (White, 2006) and the identification keys established by Virgilio et al (2014) and De Meyer and White (2016). Similarly, the parasitoids were identified by referring to the work of Bokonon-Ganta et al (2019) and the identification key developed by Wharton and Yoder (2005).…”