2026-03-31
María F. BRUGO CARIVALI, Sofía E. OLMOS, Emilia MAZZITELLI, Cecilia E. LUCIANI, Marcos G. CELLI, María C. PEROTTO, Carlos M. DE BORBÓN
This study reports the first record of Frankliniella zucchini Nakahara & Monteiro (Thysanoptera: Thripidae) in Argentina. This thrips, previously confirmed as the only vector for Zucchini Lethal Chlorosis Virus (ZLCV), was identified on squash crops ( Cucurbita maxima Duch.) in the northeastern subtropical region of Argentina, infected with ZLCV, the causal agent of lethal chlorosis of zucchini squash. In addition, the present study presents the morphological characteristics distinguishing F. zucchini from the morphologically similar Frankliniella gemina Bagnall, along with factors that may influence the potential spread of this ZLCV-bearing thrips to other favorable regions. Currently, the primary factor limiting its global spread appears to be the restricted host range of F. zucchini.
2026-03-31
Daniela FUENTES-RODRÍGUEZ, Melisa B. MULERO, Nicolás PEDRINI, Andrea V. TOLEDO
The ecological story of how a particular insect becomes an agricultural pest is crucial for understanding insect adaptations to cropping systems. Tibraca limbativentris Stål is one of the most harmful pests in Neotropical irrigated rice crops. Despite over a century of reports of T. limbativentris , there is currently no published evidence confirming its ability to complete its life cycle on native host plants under natural conditions. This work presents a comprehensive review of the published literature on T. limbativentris , with a particular focus on its alternative host plant associations in the Neotropics. A total of 198 publications mentioning the species were examined, and thirty host plant species were identified. The most frequently reported plants were Paspalum urvillei Steud., Andropogon bicornis L., and Andropogon lateralis Nees, all grasses that are common elements of the regional rice field landscape. Also, five crop plants were mentioned, yet rice remains the only crop for which the insect is consistently confirmed as a primary pest. For the remaining crops, the evidence is either anecdotal or based on samplings in experimental fields, and given the absence of recent verified reports from commercial fields, caution is advised when mentioning the association of T. limbativentris with these crops.
2026-03-31
Muhammad SARWAR
Rice yellow stem borer, Scirpophaga incertulas (Walker), is the most destructive rice insect owing to high reproductive capacity and invasiveness. Field experiments were conducted to investigate effects of chemical fertilizers in combination with biofertilizer on incidence of stem borer. Treatments included biofertilizer (containing nitrogen-fixing bacteria), nitrogen (urea), phosphorus (diammonium phosphate) and potash (muriate of potash) applied alone, besides biofertilizer + nitrogen, biofertilizer + phosphorus and biofertilizer + potash in combination, compared to none fertilizers or biofertilizer applied in control treatment. Results showed that different treatments significantly affected borer’s infestation and influenced yield components: panicle length, filled and unfilled grains per panicle and 1000 grains weight. Maximum infestation level (24.66% deadhearts, 19.66% whiteheads) was recorded in treatment where nitrogen applied alone, while minimum infestation (6.00% deadhearts, 2.66% whiteheads) recorded in treatment where biofertilizer and chemical fertilizers were used in combination. Mean grain yield was the highest in treatment with biofertilizer and all chemical fertilizers (1643.33 kg/ ha), whilst the least in control treatment (1003.33 kg/ ha). due to varying insect populations and nutrients availability to plants. Consequently, application of only nitrogen favored borer’s infestation, while addition of biofertilizer with chemical fertilizers proved antagonistic towards pest’s suppression, which ultimately enhanced grain productivity.
2026-03-31
Victoria MONTILLA, Javier A. MÁRQUEZ, Romina E. PRINCIPE
Knowledge about chironomids as bioindicators of environmental change remains limited. This study evaluated how afforestation with pine trees ( Pinus elliottii Engelm.) and subsequent logging influence chironomid communities, emphasizing taxonomic resolution at the genus level. Over four years (2008, 2012, 2014, and 2015), samples were collected from three forested streams (subsequently logged) and three reference streams in grasslands in the Santa Rosa sub-basin, Córdoba, Argentina. Using stereoscopic and compound microscopes, 20 taxa with different community compositions were identified according to land use. Multivariate analysis and PERMANOVA revealed significant differences between riparian vegetation types. Correspondence analysis separated the communities of standing pine plantations from those of felled pines and native grasslands. Grassland streams harbored more indicator species, particularly Rheotanytarsus Thienemann & Bause and Pseudochironomus Malloch, while pine plantations were associated with Pentaneurini and Macropelopiini. Precise taxonomic identification enabled the detection of ecological differences between riparian vegetation types, highlighting the bioindicator potential of Chironomidae and the importance of local studies for effective ecosystem monitoring.
2026-03-31
Liliana CICHÓN, Silvina GARRIDO, Gerardo GASTAMINZA, Luis ARGARAÑAZ, Marcela GONZALEZ, Laura VARONE
The mealybug Pseudococcus viburni (Signoret), is a polyphagous pest impacting various crops, including apples and pears in the region of Alto Valle, Río Negro, Argentina. Its honeydew excretion promotes sooty mold, diminishing fruit quality and affecting marketability. Furthermore, its quarantine status complicates trade with Mexico, a key market for Argentine pears. Existing pest management practices, including insecticides, have proven insufficient due to the mealybug's cryptic behavior and treatment resistance. This study evaluates the effectiveness of a 42-day cold storage treatment at 0 °C, used as an export strategy to manage P. viburni eggs. Two cold storage conditions were tested: regular atmosphere and controlled atmosphere, with four replicates per storage treatment and one control (kept at standard rearing conditions), corresponding to four placement dates in the cold chambers. The results showed that both storage treatments achieved complete mortality of P. viburni eggs, with a treatment efficacy surpassing the probit-9 value. These findings confirm that the 42-day cold treatment meets quarantine requirements and ensures pest control. The study's outcomes validate the current cold treatment at origin protocol, simplifying post-harvest procedures for Argentine pear exports.