Levantamento de moscas-das-frutas (Diptera: Tephritidae), e seus possíveis agentes biológicos de controle em região serrana de Alagoas

Abstract

Atlantic Forest fragments known as “brejos florestas serranas” are present in the countryside of Northeast region. This work aimed at extending the knowledge on the biodiversity of fruit flies and their possible biological control agents in the mountain region of Alagoas. Tem McPhail traps were installed in five forest fragments and five domestic orchards. The trapped insects were placed in plastic vials, which were identified and sent to Laboratório de Entomologia/Acarologia da Universidade Federal de Alagoas Campus-Arapiraca. There, insects were screened, separated according to gender and genus, and put inside vials containing 70% ethanol in order to be identified at the species level. Fruits of four tree species were collected: mango tree Mangifera indica L. (Anacardiaceae), soursop tree Anona muricata L. (Annonaceae), guava tree Psidium cattleianum Sabine (Myrtaceae) and siriguela tree Spondias purpurea L. (Anacardiaceae), and sent to the Laboratory above mentioned, where they were hygienized, counted, weighed and placed in plastic trays with a layer of sterile sand, which was used as substrate for insects to pupate. After eight days, pupae were individualized and placed in Petri dishes with the bottom covered with sterile sand and kept at room temperature until adult emergence. Adults were transferred to Eppendorfs® with 70% ethanol and identified. To obtain edaphic mites, litter and soil at depths of 0-5, 5-10, 10-15 and 15- 20 cm were collected in areas of native vegetation and domestic orchard. Mites were extracted using modified Berlese-Tullgren funnel under increasing temperature at rate of 5ºC per day until reaching 65ºC. Collected specimens were quantified and stored in 1.5-mL microtubes made of PVC containing 70% ethanol. After this procedure, mites were mounted in microscopy slides using Hoyer’s medium to identify them. Classification and identification of specimens were conducted under phase contrast microscope and guided by a dichotomus identification key. To obtain entomopathogenic nematodes (EPNs), 5 sub-samples of soil (100 g/each) at a depth about 20 cm were collected and stored in 1kg-plastic bags. Samples were then homogenized at the laboratory in plastic trays and Thereafter, samples were put in 2L-plastic containers containing six caterpillars of Galleria mellonella (Lepidopterra: Pyralidae) and six of Tenebrio molitor (Coleoptera: Tenebrionidae) from a laboratory rearing serving as “live bait“ to isolate EPNs in soil samples. It was collected 792 specimens of fruit flies (656 females and 136 males) in the mountain region, being 322 (40.6%) from Forest fragments and 470 (59.4%) from domestic orchard. It was identified 695 (87.7%) specimens of Anastrepha Schiner, 1868, and 97 (12.3%) of Ceratitis Macleay, 1829. Specimens of Ceratitis capitata Wiedemann, 1824 were trapped only in orchards. It was collected 6,579 mites (imatures and adults), being 4,859 in the mountain Forest and 1,720 in domestic orchard. The majority of collected mites belonged to the suborder Oribatida 3,958 (60.2%), followed by the order Mesostigmata 1,493 (22.7%), group Astigmatina 639 (9.7%) and suborder Prostigmata 489 (7.4%). In 46 samples (76.7%) out of the 60 samples of soil collected in forest and orchard, EPNs were present. From those, 86.9 and 13.1% belongs to the genera Heterohabidits and Steinernema, respectively.