Incidence of banana leaf roller and diversity of it is parasitoids in Central Sulawesi, Indonesia

Pasaru F, Yunus M, Toana MH, Edy N, Anshary A, Saleh S. 2021. Incidence of banana leaf roller and diversity of it is parasitoids in Central Sulawesi, Indonesia. Biodiversitas 22: 5023-5029. Incidence of banana leaf roller and diversity of it is parasitoids in Central Sulawesi, Indonesia. Indonesia is still facing banana losses due to the leaf roller (Erionota thrax). Fortunately, it has several natural enemies potentially to control them. Therefore, a survey was done to measure the incidence of banana leaf roller (BLR) at different altitudes and banana cultivars as well as the diversity and parasitism of its parasitoids. The pra-imago stages of BLR were collected at different altitudes and banana cultivars in Central Sulawesi, Indonesia, and transported to the laboratory for rearing and parasitism observation. The study revealed that the incidence of E. thrax in the surveyed locations varied from 28.6% to 85.8%, whereas the parasitism level of the BLR parasitoids was 0.0 to 22.1%. Incidence of E. thrax tended to be higher at a higher altitude while Kepok cultivar seemed to be less prone to BLR infestation compared with Raja and Mas cultivars. A total of nine parasitoids of BLR were recorded. They were Agiommatus sumatraensis, Pediobius erionotae, Ooencyrtus pallidipes, Brachymeria lasus, Brachymeria thracis, Cotesia erionatae, Xanthopimpla gampsura, Casinaria sp, and Palexorista solennis. Among them, B. lasus was the most abundant, widely distributed, and had the highest parasitism rate. Our study figured out that BLR infestation is a major problem in Central Sulawesi. Nevertheless, the presence of parasitoids recorded in this study may potentially be used as the biological control.

Distribution of Deer Keds (Diptera: Hippoboscidae) in Free-Living Cervids of the Tuscan-Emilian Apennines, Central Italy, and Establishment of the Allochthonous Ectoparasite Lipoptena fortisetosa

Lipoptena fortisetosa and L. cervi are hematophagous ectoparasites belonging to the Hippoboscidae family and preferentially living on cervids. In recent years, they have received specific attention due to the great increase in the abundance of their host species, and to their medical and veterinary importance as possible vectors of pathogens harmful to humans and animals. The aim of this study was to investigate the parasitism level of both of these flies on their main hosts in Italy, which are red deer, fallow deer, and roe deer, and to highlight a possible preference for a species, sex, or age class among the hosts. Deer keds were collected by examining 326 cervids hunted in the Tuscan-Emilian Apennines. Outcomes showed that L. fortisetosa has greatly spread throughout the study area, where it competes with the autochthonous L. cervi. Moreover, red deer was the favored host species of both ectoparasites, while different preferences for host sex and age classes were observed in the two hippoboscids. The regular monitoring of deer ked populations, especially the allochthonous L. fortisetosa, which is continuously spreading in Europe, is recommended to expand the knowledge on these parasitic species that are potentially dangerous to public health.

Parasites in farmed Piaractus brachypomus (Serrasalmidae) in the state of Acre, western Brazilian Amazonia

ABSTRACT This study investigated the parasite fauna in Piaractus brachypomus grown in fish farms in the state of Acre, in the western Brazilian Amazon. We examined 160 fish from four farms. Overall parasite prevalence was 66.9%. The fish were parasitized by Anacanthorus spathulatus, Mymarothecium viatorum, Anacanthorus penilabiatus, Clinostomum marginatum, Echinorhynchus jucundus and Henneguya sp., but monogenean species were the dominant parasites. Monogeneans showed an aggregated distribution pattern and there was a weak correlation between host size and abundance of M. viatorum and A. penilabiatus. No difference in the condition factor of parasitized and non-parasitized fish was detected. The fish of all farms had the gills parasitized by A. spathulatus and M. viatorum, but A. penilabiatus was found only in fish from two farms. Echinorhynchus jucundus, C. marginatum and Henneguya sp. were found in only one farm. The differences in parasitism level among the farms are attributable to differences in management and quality of cultivation environments.

Impact of Abamectin on Anagrus nilaparvatae, An Egg Parasitoid of Nilaparvata lugens

Anagrus nilaparvatae (Hymenoptera: Mymaridae) is an egg parasitoid potential for controlling the major pests on rice, the brown planthopper (Nilaparvata lugens [Hemiptera: Delphacidae]).Abamectin is one of insecticides registered for N. lugens. The research was aimed to investigate the impact of contact application of abamectin on the parasitism level of A. nilaparvatae under laboratory conditions. Adults of A. nilaparvatae and the first instars as well as adults of N. lugens were exposed to the residue of abamection inside the test tube. A. nilaparvatae was much more susceptible to abamectin compared to N. lugens. Application of abamectin at the recommended concentration (22.78 ppm) for 30 min caused 100% mortality, and it reduced to 85% when the concentration was decreased to 0.36 ppm. In contrast, the mortality for the first instar of N. lugens was only 15% at 22.78 and no mortality at 0.36 ppm. No N. lugens adults died even when they were exposed to 22.78 ppm. Furthermore, the parasitism test was conducted using 38 days after planting of IR-64 rice variety. Those plants were infested with 50 females of N. lugens for 2 days. A. nilaparvatae were exposed by contact to 0.02, 0.23, and 2.28 ppm of abamectin. The survivors were released to the rice plant containing eggs of N. lugens. Contact application of abamectin reduced parasitism level of A. nilaparvatae as much as 86.34, 70.01, and 28.43% with concentrations of 2.28 ppm, 0.23 and 0.02 ppm, respectively. In addition, the number of parasitoids emerged decreased with increasing concentration of abamectin. These results suggest that abamectin could be detrimental to A. nilaparvatae due to direct mortality, reduced the parasitism level, and decreased the number of progeny produced. IntisariAnagrus nilaparvatae (Hymenoptera: Mymaridae) merupakan salah satu parasitoid telur yang berpotensi untuk mengendalikan hama utama tanaman padi, wereng batang padi cokelat (Nilaparvata lugens [Hemiptera: Delphacidae]). Abamektin adalah salah satu insektisida yang terdaftar untuk pengendalian N. lugens. Penelitian ini bertujuan untuk mengetahui dampak aplikasi kontak abamektin terhadap suseptibilitas dan tingkat parasitasi A. nilaparvatae terhadap telur N. lugens pada kondisi laboratorium. Imago A. nilaparvatae serta instar satu dan imago N. lugens dipapar dengan residu abamektin di dalam tabung reaksi. A. nilaparvatae lebih peka terhadap abamektin dibandingkan N. lugens. Aplikasi abamektin pada konsentrasi anjuran (22,78 ppm) selama 30 menit menyebabkan mortalitas A. nilaparvatae 100%, dan mengurangi sampai dengan 85% pada konsentrasi yang lebih rendah 0,36 ppm. Sebaliknya, mortalitas instar satu N. lugens hanya sebesar 15% pada 22,78 ppm dan tidak menimbulkan kematian pada 0,36 ppm. Konsentrasi 22,78 ppm tidak menimbulkan kematian imago N. lugens. Selanjutnya, uji parasitasi dilakukan menggunakan media tanaman padi varietas IR-64 umur 38 hari setelah tanam. Tanaman diinfestasi dengan 50 ekor betina N. lugens selama dua hari. A. nilaparvatae dipapar abamektin dengan metode kontak pada konsentrasi 0.02, 0,23, dan 2,28 ppm. Parasitoid yang mampu bertahan hidup dilepaskan pada tanaman padi yang telah diinfestasi telur N. lugens. Aplikasi kontak abamektin mengurangi tingkat parasitasi A. nilaparvatae sebesar 86,34, 70.01, dan 28,43% pada konsentrasi 2,28; 0,23; dan 0,02 ppm. Selain itu, jumlah parasitoid yang muncul semakin menurun dengan peningkatan konsentrasi abamektin. Hasil ini menunjukkan bahwa abamektin dapat merugikan secara langsung terhadap mortalitas serta mengurangi tingkat parasitasi dan jumlah keturunan A. nilaparvatae.

Brassica aphid (Hemiptera: Aphididae) populations are conditioned by climatic variables and parasitism level: a study case of Triângulo Mineiro, Brazil

Cosmopolitan pests such asBrevicoryne brassicae, Lipaphis pseudobrassicae, andMyzus persicae(Aphididae) cause significant damage to Brassicaceae crops. Assessment of the important biotic and abiotic factors that regulate these pests is an essential step in the development of effective Integrated Pest Management programs for these aphids. This study evaluated the influence of leaf position, precipitation, temperature, and parasitism on populations ofL. pseudobrassicae, M. persicae, andB. brassicaein collard greens fields in the Triângulo Mineiro region (Minas Gerais state), Brazil. Similar numbers ofB. brassicaewere found on all parts of the collard green plants, whereasM. persicaeandL. pseudobrassicaewere found in greatest numbers on the middle and lower parts of the plant. While temperature and precipitation were positively related to aphid population size, their effects were not accumulative, as indicated by a negative interaction term. AlthoughDiaeretiella rapaewas the main parasitoid of these aphids, hyperparasitism was dominant; the main hyperparasitoid species recovered from plant samples wasAlloxysta fuscicornis. Parasitoids seem to have similar distributions on plants as their hosts. These results may help predict aphid outbreaks and gives clues for specific intra-plant locations when searching for and monitoring aphid populations.

Eksplorasi dan uji keragaan parasitoid penggerek buah kapas Pectinophora gossypiella Saunders (Lepidoptera: Gelechidae)

Pink bollworm, P. gossypiella, is a main pest of cotton that causes boll damage up to 70%. Recommended IPM has not effectively control this pest. The use of parasitoids of this pest is one of strategy to manage this pest population as using chemical control is expensive and caused secondary pest. This research objective is to study some biological aspects of pink bollworm parasitoids by doing exploration of the parasitoids in cotton growing areas and testing the potential candidates as biocontrol agents. The activity was conducted from April - December 2001. The research was conducted in two steps: survey and laboratory tests. The survey was conducted in East Java (Asembagus and Lamongan), Central Java (Brebes) and South Sulawesi (Bone) by collecting pink bollworm eggs and identifying the emerged parasitoids. Laboratory tests were done in Biological Control Laboratory of ITFCRI, Malang, consists of reproductive performance aspects. We found two and five species of egg and larval parasitoids, respectively. Parasitism level of egg was 81% by Tichogrammatoidea spp. and that of larva was 24% by Apanteles sp. These two parasitoids are predominant and found in all cotton growing areas. Tichogrammatoidea spp. have opportunity to be used as biocontrol agent in release program, while Apanteles sp. would have valuable role in conservation approach.

Keanekaragaman spesies parasitoid telur Helicoverpa armigera (Hübner) pada sistem tanam monokultur dan polikultur kapas

Polyculture system is one of techniques in pest management. In Indonesia, cotton is always intercropped with second food crops such as maize, soybean, mungbean or peanut. This research was aimed to evaluate the effect of culture system, i.e. cotton monoculture vs. cotton intercropped with soybean on the increase of species diversity of H. armigera egg parasitoids and the parasitoid contribution to mortality of H. armigera. The research was arranged in a split plot design with two main factors: three cotton varieties with three levels of trichome density (Tamcot SP 37, Kanesia 8 and LRA 5166) and the subplots were two cultivation systems (cotton monoculture and polyculture), with three replicates. Observations were made by collecting H. armigera eggs on population of first generation (45 days after planting) and second generation (75 DAP). The results showed that on cotton polyculture the egg parasitoid complex which consisted of Trichogramma spp. and Trichogrammatoidea spp. was higher than that in cotton monoculture and so was the egg parasitism level. The increase of egg parasitism was 24% in the first generation and 15% in the second generation. Parasitoid species found belonged to the genera Trichogramma and Trichogrammatoidea. In the parasitoid complex, Trichogrammatoidea armigera was dominant on the first generation and Trichogramma chilotraeae on the second. The domination succession could be as a result of the higher host-searching capacity of T. chilotraeae than that of T. armigera.

Keefektifan Telenomus remus (Nixon) (Hymenoptera: Scelionidae) dalam mengendalikan hama tanaman bawang daun Spodoptera exigua Hübner (Lepidoptera: Noctuidae)

The objective of this research is to study the effectiveness of T. remus as biocontrol agent for S. exigua. The study was conducted by releasing a set of T. remus females on potted onion plants that have been attacked by S. exigua. Three different parasitism level was artificially created by releasing different numbers of females: low rate parasitism (release of 4 adult females), moderate parasitism (7 females) and high parasitism level (11 females). The result of this study showed that T. remus is effective to control S. exigua population. Up to 48.2% of S. exigua. population was able to be suppressed by the high parasitism level. Rate of parasitisation was more when more adult female T. remus was released. Release of 11 adult female of T. remus can increase the population level of the parasitoid up to 24.1 times than the initial population. This express that T. remus is a mortality factor which can regulate the population of S. exigua. However, the succesfull parasitisation of T. remus is also dependent on environmental factors such as temperature, humidity, food, and host suitability.

THE INFLUENCE OF CULTURAL PRACTICE ON POPULATION OF PEA LEAFMINER (Liriomyza huidobrensis) AND ITS PARASITOIDS IN POTATO

Pea leafminer (Liriomyza huidobrensis) is the major pest of potato crop in Indonesia. The use of insecticides to control the pest is ineffective and harmful to the natural enemies. The study aimed to find out a promising cultural practice for leafminer management on potato crop. The study was conducted at a farmer’s field in Bali in 2004. Potato plants (Granola variety) were grown in a raised-bed plot of 10 m x 1 m. The treatments evaluated were standard cultural practice (C), C plus reflective plastic mulch (RPM) (CM), farmer’s practice (F), vermicompost (V), and V plus RPM (VM). All treatments were arranged in RCBD with five replications. From each plot, 10 plant samples were randomly taken to observe the presence of larvae, mines, and adults. Larvae and adults of leafminer and mines were separately counted from the top, middle, and bottom parts of the plant samples. Parasitoids were collected from the infested leaves of the plant samples. Emerged parasitoids were counted and put into vials with 70% ethyl alcohol and then identified. The results showed that the population of adults, larvae of L. huidobrensis, and mines were less in C, CM, V, and VM treatments compared to farmer's practice (F). However, RPM (CM and VM) treatments significantly reduced population of leafminer and mines. The highest population of adults, larvae, and mines on RPM treatment were less than 1.5, 8.5, and 10 per plant, respectively compared to other treatments which were greater than 3.2 for adults, 12.4 for larvae, and 12.7 for mines. Parasitoid population and parasitism level were more in vermicompost treatments (V and VM) compared to other treatments (C, CM, and F). The results showed that application of pesticides was ineffective against leafminer and reduced parasitoid population; in the other hand RPM was effective to control leafminer although the effect on parasitoids was not clear. Parasitoid species that were found associated with potato crop were Hemiptarsenus varicornis, Neochrysocharis sp., and Opius sp. Combination of RPM with standard practice and vermicompost are prospective for leafminer management in potato crop, however, VM is friendlier to environment regarding sustainable agriculture.