Presence of spiders in strata of lemon trees (Citrus limon), Montevideo, Uruguay

Abstract

Spiders present a variety of foraging strategies and prey preference, the presence of them in agroecosystems represents a dominant component among predators. Citrus fruits are significantly profitable crops and are among the most widely produced fruits and popular in the world, being in Uruguay main export fruit. Traditional pest control is performed using pesticides, causing a negative impact on spiders. The objective was to determine the distribution of the spider community in lemon crops (Citrus limon) at vertical strata and soil, comparing their abundance, richness and diversity of species, between a conventional crop (CC) vs. abandoned crop (AC). Spiders were collected manually in four vertical strata on lemon tree, stratum-0 was by pitfall traps. 1900 spiders (63% in CA and 37% in CC) at the vertical strata were collected, 84 species sharing. The stratum-0 was the most abundant (4866 ind.). The spiders at the strata level showed greater abundance, species richness and diversity, in stratum-0, stratum-3 and stratum-4, being distributed according to the structures and physiognomy of lemon tree. Only five species were present in all strata including stratum-0: Metaltella sp.1 (Amphinectidae), Aysha sp.1 (Anyphaenidae), Parawixia sp.1, Araneus lathyrinus (Araneidae), Achaearanea hirta (Theridiidae). The analysis of the results shows how the spider community is distributed in the different strata of the lemon tree, taking advantage of the structural physiognomy of the plant. Also demonstrating, how agricultural management practices can influence the spider community.