Entomofauna Associated with Agroforestry Systems of Timber Species and Cacao in the Southern Region of the Maracaibo Lake Basin (Mérida, Venezuela)

Abstract

Agroforestry systems are environment-friendly production systems which help to preserve biodiversity while providing people with a way of earning a living. Cacao is a historically important crop in Venezuela that traditionally has been produced in agroforestry systems. However, few studies have evaluated how different trees used in those systems affect the dynamics and abundance of insects. The present study evaluated the entomofauna assemblages associated with different combinations of four timber-yielding trees and four Criollo cacao cultivars established in a lowland tropical ecosystem in Venezuela. A randomized block design with two replicates was used, each block having 16 plots which included all 16 possible combinations of four native timber trees (Cordia thaisiana, Cedrela odorata, Swietenia macrophylla, and Tabebuia rosea) and four Criollo cacao cultivars (Porcelana, Guasare, Lobatera and Criollo Merideño). Insects were collected with yellow pan traps and sorted to order. Coleoptera and parasitoid Hymenoptera were determined to the family level. In total, 49,538 individuals of seven orders were collected, with Hymenoptera, Diptera, and Hemiptera being the most abundant, although only Lepidoptera and Coleoptera abundances were significantly influenced by the timber tree species. Twenty-three families of parasitoid Hymenoptera and 26 of Coleoptera were found. Significant differences in insects’ assemblages were found both in parasitoid Hymenoptera and Coleoptera families associated to every shade tree, with the families Eulophidae and Lycidae being indicators for Cordia, and Chalcididae for Swietenia. The entomofauna relationship with the cacao cultivar was barely significant, although Scydmaenidae and Scarabaeidae were indicators for Lobatera and Merideño, respectively. No significant effects were found for interaction with cacao cultivars and native trees. We concluded that the particular insect assemblages found in Cedrela odorata and Cordia thaisiana, together with their high growing rates, make these two species an optimal choice for cacao agroforestry systems.

Differences in the insect fauna associated to a monocultural pasture and a silvopasture in Southeastern Brazil

“…Formicidae was the most abundant Hymenoptera family in both systems. For this family abundance, richness and diversity were significantly higher in the silvopasture, as has been found previously 15,[66][67][68] . In the silvopastoral system this increase in ant diversity could be due to the differences in tree physiology and structural complexity, resulting in an increase in diversity 69,70 .…”

New records and a voucher collection of parasitoid wasps (Hymenoptera) inhabiting agroforestry systems in the colombian amazon basin

“…In cacao agroecosystems from Merida (Venezuela), Mazón (2015) and Mazón et al (2018) reported 33 and 23 families of parasitoid wasps, respectively. Again, the richest families were similar to what we obtained in this study: Braconidae, Ichneumonidae, Scelionidae, Pteromalidae, Figitidae, Encyrtidae, and Mymaridae.…”

Do restoration techniques and types of weed control influence the composition of edaphic entomofauna?

“…In addition to vegetation, ecological restoration implies the recovery of the entire set of attributes of the original ecosystem (Amazonas et al 2018), such as the entomofauna community. However, little is known about insect dynamics in early areas of AFS, which has remained relatively understudied (Bos et al 2007;Dantas et al 2012;Mazón et al 2018;Aquino et al 2020;Paiva et al 2020). We hypothesized that different restoration techniques and types of weed control change the composition of edaphic entomofauna.…”