EurAsian Journal of BioSciences Eurasia J Biosci 14, 7217-7221 (2020) Parasitoid and host range of Plutella xylostella L. (Lepidoptera: Plutellidae) in Bali Ketut Ayu Yuliadhi 1* 1 Integrated Pest Management Laboratory, Faculty of Agriculture, Udayana University, Bali, INDONESIA *Corresponding author: [email protected] Abstract This study aims to identify the parasitoid and the host range of Plutella xylostella L. (Lepidoptera- Plutellidae) in Bali, Indonesia. Survey was conducted between May and October 2016 and the observation was conducted in four regencies, namely Buleleng, Tabanan, Gianyar, and Bangli in the province of Bali. Cabbage and caisin plants were found in the four regencies. Cauliflower and brocolli plants were found in Tabanan, whereas collards were found in Tabanan and Buleleng. The highest average population of P. xylostella was recorded at 134.25 larvae inhabiting cabbage plants, whereas the lowest was recorded at 32.5 larvae inhabiting the collards. Two species of parasitoid Diadegma semiclausum Hellen and Cotesia plutellae were discovered in the observation. The average population of D. semiclausum was recorded at 29.25, 13.75, 9.2, 5.5 individuals inhabiting cabbage, caisin, brocolli, and collard plants respectively. D. semiclausum was not found inhabiting cauliflowers. C. plutellae were found in cabbage, caisin, cauliflower, brocolli, and collard plants. The highest average population of C. plutellae was recorded at 21.5, 11.5, 10.75, 6.5, 3.75 individuals inhabiting cauliflower, cabbage, caisin, brocolli, and collard plants respectively. Keywords: Plutella xylostella, Cotesia plutellae, Diadegma semiclausum, parasitoid Yuliadhi KA (2020) Parasitoid and host range of Plutella xylostella L. (Lepidoptera: Plutellidae) in Bali. Eurasia J Biosci 14: 7217-7221. © 2020 Yuliadhi et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License. INTRODUCTION Natural enemies (parasitoids) play an important role in suppressing P. xylostella populations. Herlinda (2004) Plutella xylostella L. (Lepidoptera: Plutellidae) suggests that there are 5 species of natural enemies generally known as Diamond Back Moth (DBM) are the (parasitoids) associated with P. xylostella (L.). The five main pest that attack cabbages or Crucifera (Talekar species are Trichogrammatoidea cojuangcoi Nagaraja dan Shelton, 1993). In addition to cabbage, P. xylostella (Hymenoptera: Trichogrammatidae), Cotesia also eat broccolli, pea, caisin, collard and various wild (Apanteles) plutellae (Kurdj.) (Hymenoptera: cabbages (Kalshoven, 1981). The larvae of P. xylostella Braconidae), Diadegma semiclausum (Hymenoptera: attack cabbages that are less than 1 month old during Ichneumonidae), and Oomyzus sokoluskii sp. seeding to cabbages that are ready to harvest (Yuliadhi, (Hymenoptera: Eulopidae). The species of D. 2015). semiclausum is only found in the highlands with a P. xylostella attack on cabbage could cause high parasitization rate of 79.2%. On the other hand, C. losses. Information obtained directly from farmers plutellae can be found in the lowlands to the highlands, indicates that it is difficult to control P. xylostella pests with a parasitization rate of 64.0%. on cabbage when the population is high. Losses due to During a survey in 2012 at a cabbage plantation in crop failure caused by P. xylostella attacks on cabbage Pancasari Village, Buleleng Regency, Bali, one species can reach 100% without insecticide application (Permadi of P. xylostella larvae parasitoid was found, namely D. and Sastrosiswojo, 1993). semiclausum (Yuliadhi, 2012). D. semiclausum is a Cabbage farmers usually use synthetic insecticides solitary endoparasitoid larvae, where the parasitoid to control P. xylostella pests. The synthetic insecticide is parent inserts its ovipositor to lay eggs into the host’s applied 5-6 times in one growing season of cabbage body (Untung, 2006), in this case into the body of P. vegetables. Excessive use of insecticides can cause xylostella larvae. many new problems, such as the death of non-target organisms, environmental pollution (soil, water and air), residues in crop yields (Sudewa et al, 2009), and the death of natural enemies of these pests. Received: October 2019 Accepted: March 2020 Printed: December 2020 7217 EurAsian Journal of BioSciences 14: 7217-7221 (2020) Yuliadhi et al. Knowing the diversity of P. xylostella host plants is Observation of P. xylostella Natural Enemies an important component in efforts to control the pest The P. xylostella parasitoid survey was carried out in population. Information about the diversity of parasitoid the same location as the host plant survey. Parasitoid species obtained in this study could be used in habitat samples were taken using purposive sampling method management. Understanding the presence of natural by choosing host plants of cabbages, which were enemies in a habitat is a priority because the host plant attacked by P. xylostella. Parasitoid samples taken from and its habitat could affect the diversity of natural each host plant consisted of 10 egg groups, 100 larvae enemies species. and 100 pupae of P. xylostella. Each sample obtained Host plants also influence the interaction between was inserted into a plastic jar with a diameter of 9 cm natural enemies, in this case the parasitoid and P. and a height of 11 cm separately based on the host plant xylostella. This study aims to determine the diversity of and location. Each jar was labeled with the sample host plant species and the diversity of parasitoid species location and time and type of plant. All parasitoid associated with P. xylostella in various kinds of cabbage samples (eggs, larvae and pupae) were taken to the plants cultivated in Bali. The information obtained will laboratory for maintenance, observation and enrich the knowledge and information regarding the identification. diversity of host plant species P. xylostella and its The P. xylostella eggs samples in the laboratory parasitoid. were kept in the jar until the parasitoids and larvae came out. P. xylostella larvae were fed according to the type RESEARCH METHODS of plant. The larvae are kept to develop into pupae, until Research Location and Period adult of the parasitoids or P. xylostella adult of appeared. The research was conducted between May 2016 and Pupae of P. xylostella samples were kept until adult of October 2016. The study consists of 2 stages, namely parasitoid or P. xylostella appeared. All adukt of field research and laboratory research. The field parasitoids and P. xylostella that appeared were research was carried out in four regencies, namely counted. Buleleng, Tabanan, Gianyar, and Bangli. The 4 regencies are located at an altitude of 640 - 1400 meters RESULT AND DISCUSSION above sea level. Laboratory research was carried out at The survey results showed that there were five the Integrated Pest and Disease Control Laboratory, species of P. xylostella host plants in four vegetable Agroecotechnology Study Program, Faculty of production centers in Bali. The five plant species are Agriculture, Udayana University. broccoli, cabbage, cauliflower, caisin and collard. Equipment and Materials Cabbage and caisin plants were found in four regencies The equipment used in this study include plastic jars of Buleleng, Tabanan, Gianyar, and Bangli. The with a diameter of 9 cm and a height of 11 cm, test tubes, cauliflower and broccoli plants were found in Tabanan cameras, microscope slide set needles, microscopes, as Regency. Collard plants were found in Tabanan well as books, journals and articles to identify parasitoid Regency and in Buleleng Regency. insect species and P. xylostella host species. The The survey results indicated that the host plant materials used include eggs, larvae and pupae of P. species affected the number of P. xylostella larvae xylostella, plants that host P. xylostella, 70% alcohol and found. The highest population of P. xylostella larvae was 96% alcohol. found in cabbage. There were 134.25 larvae recorded in cabbage, while the lowest population recorded was 32.5 Observation of P. xylostella Host Range larvae attacking collard (Fig. 1, Table 1). The field survey was conducted for two months in Based on laboratory observations of the parasitoid four regencies which are centers of vegetable emerging from P. xylostella eggs samples, no adult of production. The four regencies are Buleleng Regency parasitoid was found. Meanwhile, from larvae and with an altitude of 1400 masl, Tabanan Regency with an pupae/cocoon samples, the identification results show altitude of 640-1400 masl, Gianyar regency with an that there are 2 species of parasitoids that parasitize P. altitude of 900 masl and Bangli regency with an altitude xylostella larvae. The two species are Diadegma of 900 masl. The survey was conducted to obtain host semiclausum Hellen (Hymenoptera: Ichneumonidae) plants of P. xylostella. The host plants of P. xylostella and Cotesia plutellae Kurdjumorf (Hymenoptera: that were surveyed were determined based on Braconidae). information contained in a book on plant pests in The characteristics of adult of D. semiclausum are Indonesia written by Kalshoven (1981). Plants that were having black complexion, about 5 mm in length, yellow found with and showed symptoms of being attacked by abdomen and legs. Parasitoid larvae of C. plutellae are P. xylostella were recorded as the host plant for P. members of the Braconidae family of the order xylostella. Hymenoptera. The results of studies in several countries