MINISTRY OF EDUCATION AND TRAINING VIETNAM ACADEMY OF SCIENCE AND TECHNOLOGY GRADUATE UNIVERSITY OF SCIENCE AND TECHNOLOGY - NGUYEN THI OANH INVESTIGATION OF BIOLOGICAL, ECOLOGICAL CHARACTERISTICS OF Anisopteromalus calandrae (Howard) PARASITIZING STORED PRODUCT BEETLE PESTS IN DONG THAP PROVINCE Major: Entomology Code: 42 01 06 SUMMARY OF THE DOCTORAL THESIS IN BIOLOGY HA NOI – 2019 This work was completed at: Graduate University of Science and Technology - Vietnam Academy of Science and Technology Academic Title, Name of Supervisors: Assoc Prof Dr Tran Ngoc Lan Assoc Prof Dr Truong Xuan Lam Referee 1:………………………………………… ……………………………………… Referee 2: ………………………………………… ……………………………………… Referee 3: ………………………………………… ……………………………………… The Dissertation will be defended before the Doctoral Examination Board of Graduate University of Science and Technology - Vietnam Academy of Science and Technology at.……Date … / / 2019 The Dissertation can be accessed from: - The library of Graduate University of Science and Technology - The National Library of Viet Nam GENERAL INFORMATION The importance for doing the thesis Post - harvest losses of agricultural products are always a concern in agricultural countries, especially in tropical areas The main reason causing the demage is due to insect pests Every year, the global crop loss is about - 10% (Hodges et al., 2014) Viet Nam is one of the countries which has the highest loss of agricultural post - harvest products in Asia with from 11 to 13% rice, and from 13 to 15% maize lost (Ministry of Agriculture and Rural Development, 2009) According to the Organization of the Component of Post - harvest Processing, the loss of post - harvest rice is 11.6%, and maize is approximately 18 19% in the Red River Delta region and other regions In the Mekong Delta, the loss of post - harvest rice is about 13.7% The main way currently applied to control stored agricultural products is the chemical method by which phosphine was used However, this method cannot completely control insect pests, but it kills useful insects and other animals The method also causes chemical resistance in harmful insect pests of stored agricultural products Moreover, phosphine is toxic to human and causes contaminated environment Fortunately, a number of research on using useful parasitic species such as Hymenoptera to control the harmful pests damaging stored agricultural products have been conducted Among the parasitoids, Anisopteromalus can hinder some Coleoptera species, but no study in this subject has been carried out in Viet Nam Given the above practical and scientific requirements, this study investigates the biological, ecological characterizations of Anisopteromalus calandrae Objectives of study - To identify natural enemies for stored - product pests in Dong Thap province - To study biological and ecological characteristics of A calandrae - To evaluate the ability to control S zeamais and L serricorne by A calandrae in laboratory conditions Scientific and practical significance of the thesis Scientific significance: this thesis provides a list of natural enemy species for agricultural insect pests in Dong Thap Province Data about morphological, biological, behavioral and ecological characteristics of A calandrae parazitizing L serricorne is also obtained Besides, the ability to control S zeamais and L serricorne was shown in this study Practical significance: The obtained data are scientific background for proposing a method to use A calandrae to control agricultural insect pests in warehouses in Dong Thap Province as well as in the Mekong Delta CHAPTER I SCIENTIFIC BASIS AND DOCUMENT OVERVIEW 1.1 Scientific basic of thesis Harmful insect pests usually appear in stored agricultural products Sometimes only several weeks of storage, pests develop to high density devasting a part or most agricultural products (Bui Cong Hien, 1995) Pests cause to reduce quantity and quality of agricultural products, or even totally destroy them (Bui Cong Hien and Tran Huy Tho, 2003) Dong Thap Province located in the Mekong Delta, where a number of storehouses used for preserving agricultural products such as rice, maize, beans, etc The diversity of storehouses and stored products is a favorable condition for the spread and development of harmful insects However, the use of phosphine is the main method to control insect pests in Viet Nam as well as in Dong Thap, while the Intergrated Pest Management (IPM) has not been properly applied Thereby, determination of biological characterizations of A calandrae is necessary to control stored insect pests This study provides a biological and safe method instead of using insecticides to control these pests 1.2 Reports in the world relating to this study 1.2.1 Studies of natural enemy species for stored insect pests A number of reports on natural enemy species for harmful insects have been published For examples, Lebeck (1991) described 22 species of natural enemies for these pests Sedlacek et al (1998) recorded parasitoid species parasitizing insects damaging stored argiultural products A calandrae is one of parasitic species in families (Encyrtidae, Eulophidae, Bethylidae and Pteromalidae) recorded in Southern Africa (Helbig, 1998) In Thailand, Hayashi et al (2004) listed 29 prey species and 19 parasitoid species for stored insect pests 1.2.2 Studies of Anisopteromalus calandrae 1.2.2.1 Morphological and biological characteristics of L serricorne (a host of A calandrae) Morphological and biological characteristics of L serricorne have been determined by Visarathanonth (1985), Ryan (1999) and Mahroof and Phillips (2008) The authors also reported that the life cycle, logevity and egg laying of L serricorne depended on its food types 1.2.2.2 Morphological characteristics of A calandrae Morphological characteristics of A calandrae have been described by some authors (Hayashi et al 2004; Baur et al 2014) Some details of Anisopteromalus were described with pictures and keys to its species 1.2.2.3 Behaviors of A calandrae Biological Studies of behaviors of A calandrae such as egg laying on large - sized hosts (usually 4th larvae instar) The behaviors including host searching, host stinging have been described Moreover, the host searching at different depths (such as 14.5 cm) of the grain mass has been studied 1.2.2.4 Biological characteristics of A calandrae Studies of the life cycle and reproduction of A calandrae show that the egg stage lasts - 1.5 days on average The life cycle of the parasitoid is from 11.4 days to 26.6 days depending on temperature, host larvae and complementary food, while adult longevity was in a range of 9.6 - 26.6 days The progeny numbers produced by a female were 80.9 - 240.0 However, sometimes male longevity was only 5.4 - 6.0 days depending on its hosts The lower developmental threshold and the thermal constant of A calandrae were determined as 11.5oC and 263.2 degree - days, respectively 1.2.2.5 Ecological characteristics of A calandrae Studies of ecology of A calandrae including the competition with other parasitoid species have been published Effects of food or food supplement and host density on the development A calandrae have also been determined The investigation of temperature influence on its development shows that the life cycles are various at 20, 25, 30°C, but no statistical difference on these at the temperature of 30°C and 35°C has been found 1.2.2.6 Ability to control stored insect pests of A calandrae Previous studies showed that A calandrae effectively controlled some species for stored insect pests The performance of controlling these species ranged from 32.24% to 85.0% depending on agricultural seeds and preservation methods 1.3 Research in Vietnam 1.3.1 Research on natural enemies for stored insect pests There are only some studies of natural enemy species for stored insect pests in Viet Nam Some authors reported these subjects such as Duong Minh Tu (2005) and Tran Van Hai (2008), Nguyen Quy Duong (2010), Nguyen Van Duong and Khuat Dang Long (2017) Most studies reported species compositions in specific places, but no publication showed the presence of A calandrae 1.3.2 Studies of morphological and biological characteristics of L serricorne The investigation of L Serricorne on tobacco, hot peppers, rice and stored peanuts was carried out by Bui Cong Hien (1995) However, the Studies of morphological and biological characteristics of L serricorne damaging produced fish food have not been documented yet 1.3.3 Studies of biological characteristics, behaviors, ecology and the ability to control stored insect pests of A calandrae No research on biological characteristics, behaviors, ecology and the ability to control stored insect pests of A calandrae has been carried out in Viet Nam so far General comments of related studies in Vietnam Overall, natural species of agricultural insect pests in storehouses in Vietnam have been investigated by some authors For examples, Duong Minh Tu (2005) recorded natural species in Northern Vietnam species were recorded by Tran Van Hai et al., (2008) in Can Tho and An Giang Province In 2010, Nguyen Quy Duong described species of natural enemies for stored pests on beans in Vietnam, including parasitic species Nguyen Van Duong and Khuat Dang Long (2017) recorded species of parasitoids on maize in Son La These results showed that only some the research on natural enemies of stored - grain pests in the storehouses have been conducted Most publications have focused on recording the presence and general description of natural enemies species, but have not studied in details Studies of biology, behaviors and ecology as well as control ability of A calandrae for stored - grain pests in Vietnam have not been conducted yet CHAPTER II STUDYING SITES AND TIME AND METHODS 2.1 Time and sites for studying 2.1.1 Time for studying The research was conducted from November 2015 to December 2018 The sampling and field survey were carried out one time per month, - days per time, from November 2015 to December 2016 Further experiments were conducted in laboratory from 2016 to 2018 2.1.2 Sites for researching The investigation of natural enemy species for controlling stored agricultural products was conducted in agricultural storehouses in countryside and town sites in Dong Thap Province, including Cao Lanh district, Thanh Binh district, Lap Vo district, Chau Thanh district, Cao Lanh city and Sadec city A number of agricultural products and aquafeed types were collected from processing companies, mainly from Sadec city 2.2 Preparation of insects and scale of the study  Preparation of insects - Natural enemy species for stored insect pests - Anisopteromalus calandrae (Howard) (Hymenoptera: Pteromalidae)  Scale of the study The investigation of natural enemy species for agricultural insect pests in storehouses was conducted in Dong Thap Province The biological and ecological characteristics of A calandrae parasitized and grew on larvae of L serricorne The ability to control L serricorne and S zeamais by A calandrae was evaluated in laboratories in Dong Thap University 2.3 Proposal outline - Investigation of natural enemy species stored - product pests in Dong Thap Province - Study of characteristics of morphology, biology, behaviors and ecology for parasitoid A calandrae in the laboratory conditions, and some these characteristics of S zeamais - Study of the ability to control S zeamais and L serricorne by A calandrae in laboratory conditions 2.4 Materials 2.4.1 Materials - Catfish feed pellets (8 mm in diameter) were processed from raw materials including rice bran, broken rice, maize, soy, wheat grain and some other essential substances - Bean seeds (Vigna unguiculata), corn seeds (Zea mays) - Some Coleoptera species are hosts of A calandrae such as L serricorne (Anobiidae), S zeamais (Curculionidae) and C maculatus (Bruchidae) 2.4.2 Chemicals and laboratory devices - Stainless steel samplers, sieves, insect sweep net samplers, flashlights - Plastic containers, plastic rectangle boxes (length × width × height of 17 cm × 13 cm × cm), plastic cylinder containers (20 cm in height, 14 cm in diameter of mouth and bottom), and plastic cylinder containers (7 cm in height, 12 cm in diameter of mouth and cm in diameter of bottom); 12 CHAPTER RESULTS AND DISCUSSION 3.1 Species composition of natural enemies for stored - product insect pests in Dong Thap Province 3.1.1 Species composition of natural enemies for stored - product insect pests 13 natural enemies for stored - product insect pests were recorded during the survey for 12 months These species were in 10 families and orders of them were carnivorous species, including Tyrophagus (Dermaptera), putrescentiae Xylocoris (Acarina), flavipes and Forficula auricularia Amphibolus venator (Heteroptera), and Chelifer cancroides (Pseudoscorpionida) species are parasitoids of Hymenoptera 3.1.2 Appearance ratio of natural enemies depending on types of agricultural products in storehouse The survey results showed that there were 11 species of natural enemies appearing in all samples of rice and wheat grains 10, 9, and these species were found in aquafeed, maize grains, beans and rice bran, respectively, while only species appeared in cassava samples A calandrae was found in types of stored agricultural products with the appearance ratios greater than 80% 3.2 Morphological, biological and ecological characteristics of A calandrae 3.2.1 Some morphological and biological characteristics L serricorne - host of A calandrae All stages the L serricorne growing on aquafeed at 30 ± o 1.07 C, humidity of 74.64 ± 3.17% were recorded The results showed that the life cycle of L serricorne is 41.53 ± 6.21 days on 13 average The egg stage of the beetle was 7.10 ± 0.76 days, the 5th larvae stage was 26.4 days, pupa stage was 4.23 ± 0.82 days, while adult stage ranged from 33 to 53 days (temperature 30 ± 1.07oC, humidity 74, 64 ± 3.17%) 3.2.2 Morphologcal characteristics of A calandrae Whole body of A calandrae is dark - green color (Figure 3.8) Only males have gaster with milky white or opaque yellow colors on the 2nd, 3rd and 4th tergites When parasitizing L serricorne, females and males have a body length of 3.5 ± 0.3 mm and 2.4 ± 0.5 mm on average, respectively The compound and ocellus eyes are reddish brown An antenna has 13 segments (including scale) Legs with black coxae, black or brown, and yellow tibiae were identified Each tarsus has segments Forewings have hard hairs, speculum bare and setea on wing disc dark A space under forewings mergin has not any hair (Figure 3.8) Figure 3.8 Adults of A calandrae 14 3.2.3 Biological characteristics of A calandrae 3.2.3.1 Activity behaviors of parasitoid adult  The number of eggs in L serricorne and a host insect On larvae of L serricorne, A calandrae females usually laid an egg on a host with 82.47% Some females laid 2, 3, and eggs on a host with 10.31%, 5.62%, 1.12% and 0.47%, respectively The ratios of A calandrae emerged from a pupa with 1, 2, 3, and eggs were 85.45%, 47.27%, 28.33%, 25.0% and 20.0%, respectively  Behaviors of courtship and ovipositor - The courtship behavior of parasitoid males and the reaction of females When a male of the parasitoid encountered a female, he often run around and flirted with the female The total time that the male run, flapped their wings and moved around the female was approximately 44.80 ± 10.40 seconds Thereafter, the time that male jumped on the female’s abdomen and stroked the female’s antennae lasted 16.45 ± 2.21 seconds - Ovipositor An A calandrae male jumped on the back of the female, then moved to her abdomen to perform mating if the female agreed The sex making lasted 22 ± 2.70 seconds 15 - Successful ovipositor process and ovipositor time of A calandrae Table 3.6 Successful ovipositor process and ovipositor time of A calandrae Numbers of mating couples 16 Mating after flirting (%) Lần Lần Lần 53.33 Mating time (seconds) 87.50 ± 3.10 26.67 68.25 ± 5.31 20.00 56.67 ± 3.98  Host finding behavior of A calandrae After ovipositor for about day, females began to probe signals for finding their hosts by moving slowly on the grain mass surface A female often identified a suitable host by using their mouths and antennae for laying her eggs  Host selection to lay eggs of a A calandrae female When exposed to hosts at different age stages (stages of - 5), prepupae and pupae of L serricorne, a A calandrae female tended to choose larvae stages of the 2nd, 3rd and 4th or prepupae and pupae However, females not lay eggs on the 1st and 5th larvae 3.2.3.2 Behaviors of larvae A calandrae laid its eggs on any position on the host body After hatching, larvae of the 1st stage moved to an appropriate host and clung on the host They sucked up the nutrient fluid from the host until reaching the 4th stage and becoming pupae Larvae grew quickly from the first to the 4th stage 16 3.2.3.3 Life cycle of A calandrae parasitizing L serricorne The development of A calandrae in laboratory conditions (30 o ± 1.0 C, 75 ± 3.1% RH) is shown in Table 3.7 Table 3.7 The development of A calandrae parasitizing L serricorne Stage N0 Time (days) samples Range Mean Egg 45 1.00 - 2.00 1.22 ± 0.42 st 115 1.00 - 1.40 1.08 ± 0.12 nd 102 1.00 - 1.50 1.21 ± 0.17 rd 104 1.00 - 1.70 1.30 ± 0.16 th larvae instar 106 1.20 - 2.20 1.80 ± 0.24 Larvae instar stage 427 4.20 - 6.80 5.39 ± 0.69 Prepupae 48 0.30 - 0.70 0.49 ± 0.09 Pupae 45 7.00 - 10.00 8.58 ± 0.75 Prenatal stage 45 1.00 - 4.00 1.64 ± 0.77 13.50 - 23.60 17.32 ± 2.72 larvae instar larvae instar larvae instar Total time of female life The life cycle of A calandrae is short and shown in Figure 3.31 with 17.3 ± 2.7 days on average The time for egg development is 1.2 ± 0.4 days, larval phase was 5.4 ± 0.3 days, prepupa phase is 0.5 ± 0.1 days, pupa phase is 8.6 ± 0.7 days The time to lay eggs is 1.6 ± 0.8 days 17 Figure 3.31 Life cycle of A calandrae 3.2.3.4 Longevity, parasitic ability and egg laying of A calandrae parasitizing L serricorne When feeding with honey solution (30%), females and males of A calandrae could live 27.07 ± 2.89 and 24.33 ± 2.64 days, respectively A female laid 71.13 ± 4.24 eggs in its life with 2.65 ± 0.28 eggs/day The number of emerged adults was 55.00 ± 4.94 from a female of which 37.00 ± 4.12 females in its progeny  Egg laying rhythm of A calandrae the larvae of L serricorne During the life time, the average number of a female laid from 0.07 eggs/day on the first day to 7.4 eggs/day on the 9th day and then gradually decreased until the female died (Figure 3.33) 18 Eggs/day/female 11 13 15 17 19 21 23 25 27 29 31 Age of female (days) Figure 3.33 Egg laying rhythm of A calandrae 3.2.3.5 Temperature threshold for development In all development phases of A calandrae, the highest temperature threshold was at 12.96°C, followed by larvae stage (at 12.54°C), egg stage (at 8.77oC), prepupa (at 6.85oC), and emerged from pupae (5.78oC) The threshold for the whole life cycle is at 12.09oC 3.2.4 Ecological characteristics of A calandrae 3.2.4.1 Effects of temperature on the development of A calandrae  Life cycle time of A calandrae developed at 20oC and 75% RH When A calandrae grew at 20oC and 75% RH, its life cycle was 45.38 ± 3.45 days, which was significantly longer than that at room temperature with 17.32 ± 2.72 days 19 Table 3.10 Development of A calandrae on larvae of L serricorne (at 20oC, 75% RH) Stage development N0 Development time (days) samples Range Means Egg stage 45 2.00 - 3.00 2.63 ± 0.34 1st larvae instar 112 1.80 - 2.90 2.32 ± 0.30 nd 106 1.90 - 3.50 2.58 ± 0.41 rd 108 2.40 - 3.50 2.95 ± 0.33 th larvae instar 109 2.60 - 4.00 3.20 ± 0.31 Larvae instar stage 435 8.70 - 13.90 11.05 ± 0.35 Pupa 55 0.50 - 1.60 0.98 ± 0.23 Prepupa 45 25.00 - 32.00 27.76 ± 1.19 Prenatal stage 45 2.30 - 4.00 2.96 ± 0.34 38.50 - 54.50 45.38 ± 3.45 larvae instar larvae instar Total time of female life  o Life cycle time of A calandrae at 25 C and 75% RH When A calandrae grew at 25oC and 75% RH, its life cycle was shorter compared to at 20oC and 75% RH The results are presented in Table 3.11 Table 3.11 Development of A calandrae on larvae of L serricorne (at 20oC, 75% RH) Stage development Egg stage N0 Development time (days) samples Range Means 45 1.00 - 2.50 1.82 ± 0.48 st 105 1.00 - 1.60 1.32 ± 0.16 nd 106 1.00 - 2.00 1.37 ± 0.23 rd 108 1.30 - 2.40 1.69 ± 0.22 th 109 1.50 - 2.50 2.09 ± 0.21 larvae instar larvae instar larvae instar larvae instar 20 Larvae instar stage 428 4.80 - 8.50 6.47 ± 0.82 Pupa 51 0.50 - 1.00 0.71± 0.16 Prepupa 45 14.00 - 20.00 16.62 ± 1.50 Prenatal stage 45 1.00 - 4.00 2.19 ± 0.55 17.50 - 34.50 17.50 - 34.50 Total time of female life The development of A calandrae was apparently affected by temperature when it parasitized L serricorne When it grew at 75% RH and at 20oC, 25oC and 30oC, the life cycles were longer at lower temperatures The life cycles lasted 45.38 ± 3.45, 27.80 ± 3.51 and 17.32 ± 2.72 days at these temperatures, respectively 3.2.4.2 Effects of hosts and food supplement on the longevity, and egg laying of A calandrae Mature females and males could live for 10.73 ± 1.72 and 10.52 ± 1.98 days, respectively, when they were fed on only distilled water Meanwhile, their logevities were longer when they were fed on honey bee solutions from 10% to 50% The highest longevity of females and males were recorded when A calandrae was fed on honey solution at 30% 3.2.4.3 Effects of host density on egg production of female A calandrae The experiment showed that the number of L serricorne larvae suitable for pair of A calandrae was about 25 - 30 host larvae (Table 3.16) 21 Table 3.16 Correlation between the density of L serricorne larvae and the number of parasitic hosts, the number of parasitic eggs/hosts Density of larvae Parasitized larvae Eggs/host/day (individuals)/box (individuals)/day 20 3.87 2.67 25 2.64 1.53 30 2.51 1.08 3.2.4.4 Effects of A calandrae density on the sex ratio of their offspring parasitizing S zeamais and L serricorne A calandrae was released at different densities to control S zeamais and L serricorne The results showed that the increase of released A calandrae reduced the ratio of male to female in their descendants in general 3.3 Ability to control insect pests by A calandrae in the laboratory condition 3.3.1 Ability of A calandrae to control S zeamais fed on Vigna unguiculata After releasing 6, and 10 couples of A calandrae, the appearance of S zeamais fed on V unguiculata reduced by 30.0 ± 2.1%, 28.7 ± 1.7% and 23.1 ± 2.0%, respectively 3.3.2 Ability to control L serricorne fed on aquafeed by A calandrae After releasing 10 couples of A calandrae to control S zeamais fed on aquafeed for months, the L serricorne was reduced by nearly 85% 22 3.3.3 The ability of A calandrae to control L serricorne fed on aquafeed The experiment was carried our using 100 g tablets of aquafeed placed in a carton box After months, the number of L serricorne was reduced by 72.2 - 80.9% In another experiment carried out in a carton box containing kg the aquafeed, the number of L serricorne was reduced by 74.8 - 82.3% CONCLUSION AND RECOMMENDATION Conclusion 13 species natural enemies of stored - product insect pests in Dong Thap Province were identified These species were carnivorous species and parasitoid species, and belong to 10 families, orders 11 species were first recorded in agricultural stored - product in Dong Thap, and species were considered as natural enemy species in stored - product in Viet Nam Among these species, A calandrae was found at over 80% in 5/7 types of stored - product The life cycle of A calandrae grew on L serricorne is 17.3 days (at 30°C, 75% RH) An individual of A calandrae laid 71.1 eggs and parasitized 63.2 young larvae on average 55 individuals (37.0 females) were produced from a female A femele laid from 1.0 to 12.0 eggs/day, and from 1.0 to 5.0 eggs/host larva 82.5% females laid egg on a host 23 A calandrae has a behavior to lay eggs on hosts who hide in agricultural seeds There is no egg laid on freely moving larvae outside the seeds Females prefer to lay eggs on 3rd larvae instar and 4th larvae instar, while no egg was laid on 1st larvae instar and 5th larvae instar The developmental threshold and thermal constant of A calandrae were determined as 12.09oC and 358.9 degree - days The life cycles were 17.3, 27.8 and 45.4 days at 20oC, 25oC and 30oC The honey solution (30% honey) was a suitable nutrient supplement for A calandrae Temperature and humidity conditions also affected the development of A calandrae Its longevity was 39.1, 30.9 and 27.1 days at 20oC, 25oC and 30oC, respectively In laboratory conditions, A calandrae could reduce the S zeamais fed on while pea by 77% after months, and L serricorne fed on aquafeed by 85% after months Suggestion The application of A calandrae should be further studied The experiments about mass rearing and release of the parasitoid into small agricultural stores should be carried out The morphological, biological and ecological characteristics of A calandrae can be used as training materials for responsible people working in agricultural companies, household businesses, and agricultural product preservation system and pest investigation Obtained data in this Study of the ability to control the insect pests by A calandrae can be used to reduce the damage of agricultural products during storage 24 CONTRIBUTIONS OF THE THESIS This study is the first report on biological, behavior and ecological characteristics of Anisopteromalus calandrae parasitizing Lasioderma serricorne fed on aquafeed, which was carried out in Viet Nam This study also provides scientific data of the bioability to control Sitophilus zeamais damaging Vigna unguiculata and Lasioderma serricorne damaging aquafeed by the parasitoid, Anisopteromalus calandrae, in laboratory conditions LIST OF PUBLICATIONS RELATING THE DISSERTATION Nguyen Thi Oanh, Tran Ngoc Lan, Truong Xuan Lam, 2017 Egg - lying behavior of Anisopteromalus calandrae (Howard), an ectoparasitoid of Lasioderma serricorne (Fabricius) Academia Journal of Biology, Vol 39, No 4, pp 416 - 420 Nguyen Thi Oanh, Tran Ngoc Lan and Truong Xuan Lam, 2017 Morphological characteristics and parasitic behaviour of Anisopteromalus calandrae (Howard) parasitizing Lasioderma serricorne (Fabricius) Journal of Plant Protection, No (273), pp - 12 Nguyen Thi Oanh, Tran Ngoc Lan and Truong Xuan Lam, 2017 Efects of food supplement on reproduction, longevity an parasitism of Anisopteromalus calandrae (Howard) parasitized Lasioderma serricorne (Fabricius) Science and Technology Journal of Agriculture & Rural Development, No 21(324), pp 73 - 76 Nguyen Thi Oanh, 2017 The biocontrol of Lasioderma serricorne damaging aqua feed by Anisopteromalus calandrae (Howard) Journal of Plant Protection, No 6(275), pp 18 - 23 Nguyen Thi Oanh, 2017 Initial investigation of using Anisopteromalus calandrae (Howard) to suppress Lasioderma serricorne damaging stored feed for fish Journal of Plant Protection, No 6(275), pp 39 - 44 Nguyen Thi Oanh, 2018 Preliminary findings on potential of laval parasitoid, Anisopteromalus calandrae (Howard) ib suppressing Sitophilus zeamais Motschulsky damaging cowpea, Vigna unguiculata Journal of Plant Protection, No 4(279), pp 28 - 32 Nguyen Thi Oanh, 2016 Investigation of natural enemies of insect pests in stored agricultural products and aqua feed in Dong Tháp and Ben Tre Provinces Science and Technology Journal of Agriculture & Rural Development, No 20(299), pp 57 - 63 Nguyen Thi Oanh, Tran Ngoc Lan, Truong Xuan Lam, 2017 Prelininary findings Anisopteromalus calandrae (Howard) parasitized Lasioderma serricorne in stored peas and aqua feed Proceedings of the 9th Vietnam National Conference on Entomology Agriculture publishing house, Hanoi, pp 592 - 596 Nguyen Thi Oanh, Tran Ngoc Lan, Truong Xuan Lam, 2017 Chatacterization of Anisopteromalus calandrae (Howard) ectoparasites of coleoptera pest in stored agricultural products Proceedings of the 9th Vietnam National Conference on Entomology Agriculture publishing house, Hanoi, pp 933 - 939 10 Nguyen Thi Oanh, 2017 Some biological characteristics of Lasioderma serricorne (Fabricius) damaged aqua stored food in Mekong delta Proceedings of 7th national scientific conference on ecology and biological resources Publisher of Natural Science and Technology, Ha Noi, pp 1841 - 1846 ... storehouses in countryside and town sites in Dong Thap Province, including Cao Lanh district, Thanh Binh district, Lap Vo district, Chau Thanh district, Cao Lanh city and Sadec city A number of agricultural... parasitoid, Anisopteromalus calandrae, in laboratory conditions LIST OF PUBLICATIONS RELATING THE DISSERTATION Nguyen Thi Oanh, Tran Ngoc Lan, Truong Xuan Lam, 2017 Egg - lying behavior of Anisopteromalus. .. behaviour of Anisopteromalus calandrae (Howard) parasitizing Lasioderma serricorne (Fabricius) Journal of Plant Protection, No (273), pp - 12 Nguyen Thi Oanh, Tran Ngoc Lan and Truong Xuan Lam,