Tingkat Serangan dan Musuh Alami Spodoptera frugiperda Je. Smith pada Tanaman Jagung di Lima Kecamatan di Kabupaten Banyumas

The survey of the distribution and damage of the new pest Spodoptera frugiperda is an important activity to determine appropriate control measures. In addition, the search for natural enemies is also needed as an alternative to controlling these pests. The purpose of this study was to determine the level of damage and the types of natural enemies found in several locations in Banyumas Regency. The method used is perposive random sampling in Banyumas Regency in five sub-districts, namely Ajibarang, Baturaden, Gumelar, Kedungbanteng, and Sumpiuh. Observations were made at 08.00-11.00 WIB from March to June 2021. The results showed that the attack rate of Spodoptera frugiperda larvae varied at each observation location. The highest attack rate was in Sumpiuh and Gumelar Districts, followed by Ajibarang, Kedungbanteng and Baturaden Districts. One species of parasitoid was found, namely Apanteles sp. and 9 predators, namely Oxyopes salticus, Dermaptera, Holcocephala sp., Rainieria sp., Orius insidiosus, Dolichoderus sp., Paratrechina sp., Oecophylla sp. and Conocephalus longipennis. At the individual paraistoid level, Apanteles sp. became the most common, followed by the predatory fly Holcocephala sp. and ants Dolichoderus sp., fly Rainieria sp., ladybug Orius insidiosus, Dermaptera, ant Paratrechina sp., ant Oecophylla sp. and the grasshopper Conocephalus longipennis.

Identifikasi dan Efektivitas Berbagai Teknik Pengendalian Hama Baru Ulat Grayak Spodoptera frugiperda J. E. Smith pada Tanaman Jagung berbasis PHT- Biointensif

The presence of new pest Spodoptera frugperda J. E. Smith has the potential to reduce corn production, so its existence needs to be controlled. The aim of this research is to obtain control techniques that could reduce the intensity of S. frugiperda pest’s attack. The research was conducted from June to October 2020. The experiment was designed in a randomized block design (RBD) with 9 replications and 3 treatments consisting of non-control (NP), PHT-biointensive (BI), and synthetic pesticides. In BI treatment, neem leaf extract (25 mL/plot) and Beauveria bassiana (6,25 g/plot) were used. Meanwhile, the PS treatment used deltametrin active ingredient (3,125 mL/plot). The volume of spray used was 1,25 L. The results showed that PS control techniques gave the best results in suppressing the intensity of fall armyworm S. frugiperda attacks (0,57%-7,04%) followed by BI treatment (0%-6,89%) and NP (0,97%-8,29%). The highest pest populations overall were found in NP treatment and the lowest in PS treatment. PS treatment provided the highest production result with a cob weight of 18,6 kg/plot (24,81 tons/ha), while BI treatment of 17,00 kg/plot (22,72 tons/ha) and NP of 15,44 kg/plot (20,64 tons/ha). The results of the correlation test between the intensity of pest attacks and production results showed that the higher the pest attack, the lower the harvest weight produced. Therefore, pest control by using synthetic pesticides made from active deltametrin is declared effective in suppressing the intensity of attacks and populations of fall armyworm S. frugiperda and able to provide high production results. Keywords: corn, intensity of attack, Spodoptera frugiperda

Steneotarsonemus ananas (Acari: Tarsonemidae): a complementary description from Australian pineapples and a new pest on Neoregelia spp. (Bromeliaceae) in Costa Rica

The pineapple tarsonemid mite Steneotarsonemus ananas (Tryon), 1898 is associated with pineapple around the world, including Costa Rica. Here, we report its association with Neoregelia sp. (Bromeliaceae) for the first time. These mites damaged the plantlets considerably, affecting the esthetic quality of the product and thus causing economic losses to the local growers. This discovery prompted us to redescribe the adult females and males from the type host and locality (pineapple in Queensland, Australia) and compare it with the original description, subsequent descriptions, and material collected from the USA, Costa Rica, and Colombia on pineapple, Neoregelia, and an unidentified bromeliad. Further specimens from pineapple in Guatemala were identified as the same species and represent the first record for this country. We concur with previous observations that the original description by Tryon is not the same species in subsequent descriptions. We tentatively consider all specimens examined the same as those described as S. ananas in succeeding descriptions, i.e., Steneotarsonemus ananas Tryon sensu Beer.

The Whitefly Dialeurodes citri: A New Pest on Citrus in Tunisia?

Whiteflies invaded citrus orchards in Tunisia in the 90’s. Two species: Aleurothixus floccosus and Parabemisia myricae have been recorded successively infesting citrus and causing severe damage in Cap-Bon (North-East of Tunisia). These pests were first controlled by several insecticidal applications but with a relative efficiency. Then two biological control programs have been deployed completing the action of native natural enemies especially for P. myricae. The result was a very satisfactory control of both whitefly species, to a point that they almost disappeared from orchards for about 30 years. In 2017, a third whitefly species, identified as Dialeurodes citri, was observed during a prospection in citrus orchards in Takelsa region (Cap-Bon). It was a common species in Algeria, but never caused damage in Tunisia. In 2020, D. citri was found again with very high population densities in the regions of Menzel Bou Zelfa (Cap-Bon) and Tunis. These observations confirmed its change of status and spread in Tunisia. The main morphological and biological traits to distinguish between D. citri and the other two whitefly species, already recorded in Tunisia, were described and first observations on its infestation were reported. Some recommendations to manage this new pest are given.