Philippine Journal of Crop Science (PJCS) April 2012, 37 (1):47-56 Research Note Copyright 2012, Crop Science Society of the Philippines Expansion of Local Geographic and Host Ranges of Nipaecoccus nipae (Maskell) (Pseudococcidae, Hemiptera)inthe Philippines with New Records of Predators and Attending Ants Merdelyn T. Caasi-Litl*, Ireneo L. Lit, Jr.2' 3 and Ariel R. Larona3 'Institute of Plant Breeding, Crop Science Cluster, College of Agriculture, University of the Philippines Los Banos (UPLB), College, Laguna 4031, Philippines; 2 Institute of Biological Sciences, College of Arts and Sciences, UPLB, College, Laguna 4031, Philippines; 3 Museum of Natural History, OVCRE, UPLB, College, Laguna 4031, Philippines;* Corresponding Author, [email protected] The local geographical distribution of the buff coconut mealybug (BCM), Nipaecoccus nipae (Maskell) (Pseudococcidae, Hemiptera) has widened since its initial invasion of Luzon Island in the early 2000s, being now known to occur in other islands and provinces of the Philippines. Surveys were conducted in several regions by initially inspecting known hosts of BCM and other plants. Samples of BCM and of host plants were collected, the latter identified to species. Seventeen (17) plant species belonging to 12 families are recorded as new hosts of BCM, bringing its total known host plants in the Philippines to 71 species in 20 families. An updated host list was prepared to include all local plants that serve as hosts of this invasive species. New associated organisms are also reported for the first time. These include larvae of the green lacewing, Mallada basalis (Walker) (Chrysopidae, Neuroptera) and the brown lacewing, Micromus igorotus Banks (Hemerobiidae, Neuroptera) that have been observed to prey on nymphs and adults, the first known locally available natural enemies of BCM. The black ants, Dolichoderus thoracicus (Smith), fire ants, Solenopsis gem inata(Jerdon),andcrazyants,Anoploiepisgracilipes(Fabricius)(Formicidae, Hymenoptera), are also now occasionally observed to attend to BCM colonies. Keywords:Anoplotepis gracilipes,Buff coconut mealybug,Dolichoderus thoracicus, Mal lada basalis, Micromus igorotus, Nipaecoccus nipae INTRODUCTION such need, the authors are continuing studies, albeit limited, despite the lack of funds or other support for a Thebuffcoconutmealybug(BCM,Figure 1), sustained series of biological and ecological studies. Nipaecoccus nipae(Maskell),is a relatively recent This paper aims to:i) update local distribution data introduction (ca. 2000) into the Philippines and was and reflect therein the spread of its geographic range formally reported as an invasive pest by Lit et al. in the Philippines; ii) report new results gathered in the (2005, 2006a, 2006b). Locally, concern about its continuing documentation of host plants infested by effects on the coconut industry was first expressed by BCM from 2000 to June 2011 by updating the list of farmers and gatherers of tuba, the sweet liquid that is host plants of this polyphagous insect; and iii) record processedinto lambanog', alocallyproduced its new associated ants and local natural enemies in alcoholic beverage similar to gin or vodka. Already an the Philippines. export product, lambanog producers were worried they may not be able to sustain and fulfill orders from abroad if the decline in sap yield continues due to the MATERIALS AND METHODS sucking insects. Other farmers like those raising sweetsop(atis),Annona squamosaL.,inLobo, Survey of BCM and Documentation of Infested Batangas also reported declining fruit yield, dying Host Plants trees and abruptly diminished or lost potential income Surveys were conducted in different areas of the (Caasi-Lit et al. 2008; Caasi-Lit et al. 2009a). country whenever possible, from January 2006 to Since its introduction, the buff coconut mealybug has September2011andinvolvedconvenienceor gradually spread to other localities and colonized opportunitysampling,without structuredsampling other host plants (Caasi-Lit et al. 2008; 2009).The design as long as the criteria for host-herbivore lack of basic biological studies especially under local association are satisfied. Such surveys generally tropical conditions and even in other countries where started among plants identified as hosts of BCM after the BCM isknowntooccur has consequently the initial survey in 2002 (Lit et al. 2006) and onwards. prevented entomologists from prescribing effective, New locality records were plotted on a map as soon practical and long-term solutions to affected local as occurrences of BCM therein were confirmed. government units and concerned farmers.Realizing Some areas were visited more regularly than the Figure 1. The buff coconut mealybug, Nipaecoccus nipae (Maskell) on Freycinetia multiflora (A), Annona squamosa (B) and Carludovica palmata (C,D), showing the different stages: female (F); males, in pupal wax cocoons (MP); and nymphs (N), the first instar of which is called crawler (Cr). others. Theseincludevariousplacesinthe Kudarat.The rest of the provinces listed among the CALABARZON provinces (except Rizal) and Metro new locality records and the provinces of Benguet, Manila, Davao City and Davao del Norte (at least Mountain Province, and Ifugao were only visited once twice a year), Polillo Island (1-2 times a year since or twice within 2006-2011. 2002); Isabela, Nueva Ecija, NuevaVizcaya, Pangasinan, Saranggani and South Cotabato (6-8 Updating the List of Host Plants of BCM times a year from 2008-2011), Marinduque (1-2 times To qualify as a host, a plant had to be infested not just a year since 2008) and Bulacan, !locos provinces by a single individual but by colonies which would (once a year since 2009).In June, 2007, a survey include nymphs, adult females and adult males, sponsored by the Bureau of Plant Industry was usually in their waxy 'cocoons'. There should be clear conducted in Regions 11 and 12 in Mindanao to signs of feeding such as yellowing of portions of document the extent of BCM infestation in several plantswherethe BCM individualswere found, agricultural areas in 6 provinces, namely: Davao del honeydew deposits, and/or growth of sooty molds on Norte, Davao del Sur (including Davao City), North surfaces where honeydew droppedor gathered. Cotabato, Saranggani, South Cotabato and Sultan Photographs of host plants and also the 48 Expansion of Host Ranges of Nipaecoccus nipae corresponding herbarium specimens, when necessary, were taken.Specimens of mealybugs were collected and preserved at least in 95% ethanol for proper documentation and verification. To determine the extent of BCM infestation, the list from Lit et al. (2006) was updated. Botanical names werecheckedandverifiedwithnomenclatural databases and/or confirmed with the assistance of botanist curators of the University of the Philippines Los Banos (UPLB) Museum of Natural History. Search for natural enemies and associated ants Alongside the continuing survey of BCM and its host plants,natural enemies and associated ants were noted, collected and preserved together with the mealybugs. Predators were reared to adult stage whereas attending ants were preserved in vials of 95% ethanol. All predators and ants were also identified to species level whenever possible. RESULTS AND DISCUSSION Local Geographical Distribution The geographical range of N. nipae in the Philippines continued to widen since its introduction in the early part of this millennium.Lit et al. (2006) reported its initialoccurrence in Laguna province among ornamentalpalms andthenintheneighboring provinces of Quezon, Batangas and Cavite (Figure 2). They also noted the introduction to Davao City in Mindanao probably also via ornamental palms. During that time, no BCM individuals or colonies were found Figure2. Geographical distribution of the buff coconut in other places visited in the Southern Tagalog region, mealybug, Nipaecoccus nipae (Maskell) in the as well as in the Davao and Cotabato provinces. Philippines. Legend: black circles - distribution as of 2005 (based on Lit et al. 2006); 0- new Since 2006, the local distribution expanded and BCM locality records determined through surveys is now known to be present in nearly all major islands from 2006 to 2011. and provinces (Table 1, Figure 2). The presence of BCM in Rizal (part of the CALABARZON subregion) To emphasize the expansion of geographic range of and in Metro Manila is now confirmed. Itis also BCM,itis worth mentioning the survey that was present in the island of Polillo which is politically a part conducted in Regions 11 and 12 in Mindanao in June of Quezon.South of the CALABARZON areas, the 2007.Initially, the data may be said to only confirm BCM is now also known in Albay, Camarines Sur and thepresenceof BCM inthesurveyedareas. Sorsogon, as well as in three islands/provinces of However, it is noted that there were no traces of BCM MIMAROPA subregion (Marinduque, Oriental Mindoro in 2007 around Tagum and Panabo cities in Davao and Palawan.Towards the northern part of Luzon, del Norte, which was just about 30-40 km from Davao the occurrence of BCM is now confirmed in the City and yet the incidence of BCM was observed to be provinces of Bataan, Benguet, Isabela, Nueva Ecija, abundant among coconuts and bananas in 2009. The Nueva Vizcaya, Pangasinan and Zambales. All infestationin Tagum City has been observed on occurrences of BCM in the Visayan islands of Leyte various species of palms planted around the city since (Leyte Province),Bohol, Cebu, Negros Occidental 2009. Moreover, considering