316 AGRIVITA Journal of Agricultural Science. 2019. 41(2): 316–324 AGRIVITA Journal of Agricultural Science www.agrivita.ub.ac.id Diversity and Community Structure of Arthropods on Rice Ecosystem in Aceh J. Jauharlina *), H. Hasnah and M. Ikram Taufik Faculty of Agriculture, Universitas Syiah Kuala, Banda Aceh, Indonesia ARTICLE INFO ABSTRACT Arthropods biodiversity on a rice ecosystem plays an important Keywords: role related to the pest management. This research aimed to Biological control investigate the diversity and community structure of arthropods in the Food crop rice ecosystem. It was conducted in Lembah Seulawah, Aceh Besar Natural enemies Regency, Indonesia from February to August 2016. Sweep net was Parasitoid used to collect insects on four rice plots at 35, 45 and 55 days after Predator transplanting (DAT) as vegetative, transition and generative stages respectively. The result showed that the twenty-five morpho-species Article History: found at vegetative stage was the highest among the three stages. Received: February 13, 2019 Accepted: May 31, 2019 They were categorized as phytophagous insects, spiders, predatory insects, parasitoid, and neutral insects. Each arthropod’s *) Corresponding author: category the highest among the three stages was in the higher E-mail: [email protected] abundance at vegetative stage, except for phytophagous arthropod. The Shannon-Wiener diversity index (H’) was significantly higher at vegetative stage than those at remaining stages, while Simpson Dominance (C) and Species Evenness (E) indices were not significantly different among the three observed stages. INTRODUCTION (Gill & Garg, 2014). Integrated Pest Management (IPM) strategies have been developed in order to Rice (Oryza sativa L.) is most important control rice pests. Integrated Pest Management is cereal crops in Indonesia. Rice plantation is a rapid defined as a holistic strategy to decrease plant pests changing ecosystem due to the change of activities and diseases using all available and compatible during cultivation. These activities affect the pest methods, but minimizing the use of chemical population and also the abundance of their natural pesticides (Matthews, 2003; Stenberg, 2017). enemies in the rice field (Khaliq, Javed, Sohail, & Several methods of pest control which are more Sagheer, 2014; Tsutsui, Kobayashi, & Miyashita, environmentally friendly such as biological and 2018). Some of the insect pests that are known mechanical controls, and also botanical pesticides to harm the rice plantation are Leucopholis rorida are employed in IPM (Borkhani, Rezvanfar, (Fabr.), brown plant hopper Nilaparvata lugens Fami, & Pouratashi, 2010). The Integrated Pest (Stål), rice shoot fly Atherigona oryzae (Malloch), Management has been adopted formally as the white stem borer Scirpophaga innotata (Walker), principle of plant protection in Indonesia through and rice bug Leptocorisa oratorius (Thunberg) the government regulation number 12 in the year (Ooi, 2015; Thorburn, 2015). 1992. Years before that (the mid-1980s) IPM was The increase of Indonesian population has introduced to Indonesia as a new crop management also driven a higher need of rice production, however approach particularly for rice plantations and many rice farmers are still very much dependent developed the Farmer Field School (FFS) model of on chemical pesticides (Kalsum & Romza, 2013). empowering farmers to make their own decisions The excessive use of chemical pesticides i.e. regarding management of their rice field. However, insecticides can lead to pest resistance, resurgence, FFS was no longer practiced since the late 1990s, the killing of non-target organisms (such as natural and nowadays, rice farmers tend to use pesticides enemies), ground water contamination, change of with many negative consequences occur in the field soil microbial diversity, and risks to human health (Thorburn, 2015). ISSN: 0126-0537 Accredited First Grade by Ministry of Research, Technology and Higher Education of The Republic of Indonesia, Decree No: 30/E/KPT/2018 Cite this as: Jauharlina, J., Hasnah, H., & Taufik, M. I. (2019). Diversity and Community Structure of Arthropods on Rice Ecosystem. AGRIVITA Journal of Agricultural Science, 41(2), 316–324. http://doi.org/10.17503/agrivita.v41i2.2160 317 J. Jauharlina et al.: Diversity and Community Structure of Arthropods on Rice Ecosystem ........................................... There have been many studies conducted arthropod species and to investigate the diversity to preserve beneficial organisms such as natural and community structure of arthropods on the enemies which can be used as biological control conventional rice ecosystem grown by local farmers. agents (Ovawanda, Witjaksono, & Trisyono, 2016; The results can be used in assessing conservation Sanda & Sunusi, 2014). These natural enemies plan of natural enemies on the rice ecosystem in (predators and parasitoids) instinctively can also play order to promote natural and biological controls as an important role in regulating the pest population. part of IPM approach. Therefore, the maintenance of biodiversity, including predator and parasitoid, within the rice ecosystem MATERIALS AND METHODS is important to enhance their role in natural control Arthropod Samplings or as biological control agents (Ueno, 2013). After The research took place in Lembah rice establishment, arthropod species colonize and Seulawah District, Aceh Besar Regency from increase diversity progressively. Their communities February to August 2016. The research site was may vary with the environment, cropping patterns, one of rice production area in Aceh Province, varieties and cultivation practices. having an altitude of 360 m above sea level. The Biodiversity refers to the species variety or arthropod samples were taken by using sweep nets number present in an area or ecosystem (Price, from four plots that belong to local farmers in two Denno, Eubanks, Finke, & Kaplan, 2011). Rice nearby villages. The plots size ranged from 1500 m2 fields often support high levels of biodiversity and up to 3400 m2 (Table 1). All rice fields in this area play important role in the systems of agricultural were surrounded by secondary forest ecosystem productivity. An important aspect of IPM is to enhance consisting different species of plants. The same natural control in the rice plantation, therefore, the variety of rice (Inpari-36) was planted in each plot. presence of various species of arthropods and There was no particular treatment applied to the their population ecology are important things to plots. Rice cultivation was employed as commonly be considered when designing pest management practiced by the farmers. In this area, pesticides methods. The arthropod community in rice fields application was quite high, ranged from two to four is known to have different ecological roles; they times during the rice plantation. include pests, natural enemies (predators and This research was conducted from February parasitoids), saprophytes and aquatic arthropods. to August 2016. The samplings were done between These different groups can perform a stability in rice 07.00 – 10.00 a.m. using a sweep net on at least 10 field ecosystem (Luo, Fu, & Traore, 2014). Many % of plot size consisting five sub-areas in each plot. studies in Asia have shown that when the use of The five sub-areas were selected in a diagonal way, pesticides was reduced to conserve the predator four on the outer sides and one in the middle of each communities, the destruction of rice plantation plot. The samples were collected at least one meter by the insect pests such as N. lugens decreased from the edge of each plot in order to reduce edge (Thorburn, 2015). effects. The arthropod samples were taken mainly One of the major limitations in promoting the ones flying above and near the surface of the natural and biological controls as part of IPM rice plantation. The arthropods were sampled three strategies is that not many farmers realize the role times i.e. at 35, 45, and 55 days after transplanting of arthropod groups found in their rice fields. They (DAT) as representation of vegetative, transition, cannot differentiate pests from beneficial organisms, and generative stages of rice growth respectively. and they often just apply pesticide when they see All sampled arthropods were kept in plastic bottles species of arthropods in the rice field. Aceh Besar containing 70 % ethanol and were brought to the Regency is one of the centers for rice production in Biological Control Laboratory, Agricultural Faculty, Aceh Province. Based on our preliminary interview Syiah Kuala University for further identification. with the rice farmers in this area, most of them think The collected arthropods were then classified into that any insect or other arthropods found on the rice five groups: phytophagous insects (pests), spiders, plantation are pests that damage the plants. The predatory insects, parasitoid, and neutral insects. fact that some of the arthropod groups are beneficial Individual number of each Arthropod category was in regulating pest populations is new information calculated to define its population. for them. This research was conducted to identify Copyright © 2019 Universitas Brawijaya 318 J. Jauharlina et al.: Diversity and Community Structure of Arthropods on Rice Ecosystem ........................................... Data Analysis in each plot of the study. Besides, the arthropods The differences among the number of samples were taken using one