Héctor Cabrera-Mireles

Edaphic fauna is a determining factor for the maintenance of soil productivity. Other factors such as soil management can modify edaphic fauna communities and directly interfere with the ecosystem services they provide. The objective of this study was to evaluate the structure of edaphic faunal communities under different conservation tillage systems in Los Tuxtlas, Veracruz, Mexico. Six tillage systems were evaluated for soil conservation in maize plots, SL1: without soil removal and covered with Mucuna sp. residues; SL2: with soil removal and residue burning; SL3: with soil removal and residue incorporation; SL4: without soil inversion and covered with maize residue; SL5: with soil removal and no residue; SL6= without soil removal and maize residue. According to Jaccard’s similarity coefficient, the most similar tillage systems in relation to the species present are the systems with soil removal and residue incorporation (SL3) and without soil removal and with maize residues (SL6) with a value of 0.83. The tillage systems with the greatest richness, diversity and equity of edaphic fauna were with soil removal and residue incorporation (SL3), without soil inversion and covered with maize residue (SL4) and without soil removal and with maize residue (SL6), mainly in the rainy season, which is the season that most affected the edaphic fauna communities

To determine the natural parasitism in fruit fly populations in disturbed areas adjacent to commercial mango orchards in the states of Chiapas and Veracruz, Mexico, we recorded over one year the fruit fly–host associations, fly infestation, and parasitism rates in backyard orchards and patches of native vegetation. We also investigated the relationship between fruit size, level of larval infestation, and percent of parasitism, and attempted to determine the presence of superparasitism. The most recurrent species in trap catches was Anastrepha obliqua (Macquart), followed by Anastrepha ludens (Loew), in both study zones. The fruit infestation rates were higher in Chiapas than in Veracruz, with A. obliqua again being the most conspicuous species emerging from collected fruits. The diversity of parasitoids species attacking fruit fly larvae was greater in Chiapas, with a predominance of Doryctobracon areolatus (Szépligeti) in both sites, although the exotic Diachasmimorpha longicaudata (Ashmead) was well established in Chiapas. Fruit size was positively correlated with the number of larvae per fruit, but this relationship was not observed in the level of parasitism. The number of oviposition scars was not related to the number of immature parasitoids inside the pupa of D. areolatus emerging from plum fruits. Mass releases of Di. longicaudata seem not to affect the presence or prevalence of the native species. Our findings open new research scenarios on the role and impact of native parasitoid species attacking Anastrepha flies that can contribute to the development of sound strategies for using these species in projects for augmentative biological control.