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In the American continent, the sugarcane borer Diatraea saccharalis (F.) is the main pest in sugarcane producing areas. The objective of this study was to assess the effect of crop residue management on damage by D. saccharalis, its egg parasitoids and the ants associated with sugarcane. The study was carried out during 2011-2012, 2012-2013 and 2013-2014 crop cycles, in three commercial fields located in different regions of Tucumán state, Argentina. Two types of crop residue management (= treatments) were compared: conservation of trash at the soil surface (CT) and trash burning (TB). In 'trash conservation' treatment, crop residue was allowed to remain over the soil surface during the whole sugarcane growing season, while the second treatment consisted of complete burning of trash blanket approximately 2 weeks after harvest. The injury level was measured by recording the number of stalks bored and internodes bored. Parasitism was estimated by counting the total number of eggs and number of black eggs (which indicates the occurrence of egg parasitoids). Ants (Formicidae) richness was calculated by two estimators; abundance-based coverage estimator and incidence-based coverage estimator, using the non-parametric richness estimators: Chao 2 and Jackknife. Finally, the indicator value was estimated through the measurement of specificity and fidelity. In all the parameters studied no significant difference was found between TB and CT treatments.

Parasitoid's performance is subject to parasitism decisions influenced by host quality and parasitoid's age. We evaluated parasitism, emergence, and the progeny sex ratio proportions of Telenomus podisi (Ashmead), Trissolcus urichi (Crawford), and Trissolcus basalis (Wollaston) (Hymenoptera: Platygastridae) females of different age attacking Piezodorus guildinii (Westwood) (Hemiptera: Pentatomidae), an important soybean pest. Eggs were offered to females of T. podisi 1-10 d old, T. urichi 1, 3, 4, or 6 d old, or T. basalis 1-6 or 8 d old. Average egg parasitism proportions were 0.71 and 0.79 to T. podisi and T. urichi, respectively; and preimaginal survivorship was >97% for both species. Trissolcus basalis females 1, 2, and 3 d old did not parasitize P. guildinii eggs, and high parasitism proportions were recorded from older females, but only 0.5 of females attacked host eggs. A greater proportion of males were produced in the progeny of T. podisi and T. urichi as maternal age increased, but no differences were found in the progeny of T. basalis wasps of different ages. The results from this study indicate that performance of T. podisi and T. urichi would not be affected by the age of the females. However, aging would induce T. basalis females to attack P. guildinii, although it is known that their main host is Nezara viridula (L.) (Hemiptera: Pentatomidae). Under certain circumstances, such as shortage of preferred host availability, high egg load, and short life expectancy, this wasp may include P. guildinii as a host.

Trissolcus basalis has been used as a biological control agent of its main host, Nezara viridula, in many countries. However, estimations of its functional and numerical responses in the field are lacking. We estimated the density of N. viridula eggs, the proportion of parasitized N. viridula eggs, and the number of T. basalis adults/trap in the field. We transformed relative parasitoid density to an absolute density, and estimated the parasitoid's attack rate, a, and the mutual interference parameter, m, in two ways: following Arditi & Akçakaya (1990) and using the Holling-Hassell-Varley model with two iterative techniques. The attack rate estimated by both methods were a=1.097 and a=0.767, respectively. Parameter m varied less between methods: m=0.563 and m=0.586, respectively, and when used to calculate the number of parasitized N. viridula eggs per m2, differences with the observed values were not significant. The numerical response of T. basalis was affected by the sex allocation of their progeny and the proportion of adult parasitoids trapped decreased with field parasitoid population density. Theoretical models show that 0

The American tribe Proconiini (Hemiptera: Cicadellidae: Cicadellinae) is one of the largest groups of xylem-feeding insects and includes the majority of the known vectors of xylem-born phytopathogenic organisms. The significance of the pathogens that this group transmits gives them an important role as pests, mostly for citrus fruit, grapes, and almonds. Knowledge of these Hemiptera in Argentina is insufficient and fragmentary. Thus one of the aims of this paper is to summarize the available information of the Proconiini sharpshooters in Argentina. In addition, 14 species are mentioned for the first time in the country, and new distributional data are given for 18 species. Thirty-four new associations between sharpshooters and host plants are recorded. New records of egg parasitoids are given for Dechacona missionum, Molomea consolida, M. lineiceps, and Tapajosa similis.