Mealybugs - an Invasive Research Consternation to Agricultural and Horticultural Crops

Popular Article Journal Home: www.bioticainternational.com Article: RT547 How to cite this article? Biotica Pirithiraj et al., 2021. Mealybugs - An Invasive Research Consternation to Agricultural and Horticultural Crops. [Biotica Research Today 3(4): 246-251. [ Today Abstract 246 nsect pests are major concern to agricultural and horticultural Vol 3:4 crop plants and cause significant yield reduction. Recently 2021 251 Imealybugs emerging as an important insect pests, causes severe threat to crop cultivation and intricate to manage. Mealybugs are found almost in all the countries around the world causing severe Mealybugs - An damage to crop plants directly by sucking the sap and indirectly by transmitting the disease. Getting rid of this pest without having prior Invasive Consternation idea on their morphology, distribution and biology will be searching a ring in the ocean. Hence this paper deals and focused on mealybug to Agricultural and species identification, distribution, host range, life cycle and mode Horticultural Crops of transport with the possible management strategies. U. Pirithiraj1, R. P. Soundararajan2* and Introduction M. Chandrasekaran2 ecent trends in changes of weather conditions, global warming and increase in the atmospheric temperature 1Anbil Dharmalingam Agricultural College and Research have influence on agricultural crop production. Insect Institute, TNAU, Tiruchirappalli, Tamil Nadu (620 027), India pestsR are also having great interactions with these changes 2Horticultural College and Research Institute for Women, and influence the crop damage. Several unimportant insects TNAU, Tiruchirappalli, Tamil Nadu (620 027), India become major insects now and causes severe attack on crop plants thereby significant yield reduction was noticed. Mealybugs are one group of insects which act as minor pests and occasionally cause damage to plants in the early period. Open Access But recently these insects are emerging as important and serious pests on various crops. Most of the mealybug species Corresponding Author were known as invasive, entered to India and established R. P. Soundararajan well in our tropical agro ecosystem. They cause great loss e-mail: [email protected] to annual and perennial crops like cereals, pulses, oilseeds, vegetable and fruits. Mealybugs are soft-bodied, wax coated, small insects that were found in clusters. They belong to the family Pseudococcidae. The naming of mealybug was due to Keywords the wax secretion of the insect. The physiology of the insect Crops, IPM package, Mealybugs, Pseudococcidae was different from other insects where waxy secretions from trilocular dermal pore. The insect causes damage to plants by sucking the sap from phloem vessels. The insect after ingestion of nutritious sap from phloem, excrete honeydew as a byproduct or excess fluid of digestion. Excretion of this honeydew invites fungi such as Capnodium sp., Cladosporium sp. and Fumago sp. etc. that cause sooty mould to the host crop. Global warming might be considered as one of the major reason for outbreak of many sucking pests which includes mealybugs. In recent years population buildup of this pest is increased in India among various agricultural and horticultural crops. It is important to have adequate knowledge on identification of mealybug species not only to Article History assess their ecological distribution but also to manage it in Received in 11th April 2021 more appropriate way. As a general phenomenon ‘Prevention Received in revised form 19th April 2021 is better than cure’. Preventive measures along with integrated Accepted in final form 20th April 2021 pest management (IPM) are handy and economic, elsewhere in managing the pest. With this view the paper discuss on E-mail: [email protected]

commonly occurring mealybug species and their management Nadu and Karnataka (Figure 1a). Striped mealybug, Ferrisia strategies. virgata Cockerell is becoming as one of the major threat to sandalwood tree that can cause complete failure of their Different Species of Mealybug and farming. It is found to transmit badnavirus diseases of cocoa and black pepper. Since it reproduces rapidly in tropical Their Distribution climates it infests tropical crops such as fruits and nuts (Figure In general all the species of mealybugs looks similar with slight 1b). Citrus mealybug, Planococcus citri Risso is a sporadic morphological difference (Table 1). Long-tailed mealybug, pest of citrus. Other than citrus it infests banana, starfruit, Pseudococcus longispinus Targioni Tozzetti feeds on a number cocoa and flowering ginger and cause considerable damage of crops including citrus, grapes, pear and pineapple etc. in to the crop. The pest is noted for its severe damage on coffee India it is distributed in Assam, Andra Pradesh, Sikkim, Tamil plantations on kenya during 1930’s (Figure 1c). Table 1: Identification, distribution and host range of different species of mealybugs Sl. Common name Scientific name Scientific name Scientific name Scientific name No. 1 Long-tailed Pseudococcus Anal wax filaments 111 countries Citrus, grapes, pear, pineapple, mealybug longispinus are across the world avocado, ornamentals, orchids and as long as body and 5 states in common in greenhouse plants etc. India. 2 Striped mealybug Ferrisia virgata Two dark brown 112 countries Guava, sapota, cotton, tomato, stripes on dorsum across the world brinjal, pepper, hibiscus, sugar with very long thin and 17 states in apple, cocoa, cassava, amaranth and wax filaments India. plumeria etc. 3 Citrus mealybug Planococcus citri One dorsal median 164 countries and Ornamentals, vegetables, grapes, stripe is present on 10 states in India. annona, lily, citrus, coconut, dorsum of adults coleus, cactus, croton, muskmelon, primrose, yam, milkweed, mango, banana, date palm, guava, soya bean, tulip and cacao etc. 4 Solanum Phenacoccus Body covered with 25 countries Solanaceous crops, cotton, brinjal, mealybug solani short waxy filaments. including India. okra, tomato, sesame, sunflower Long tails and stripes and china rose etc. on body are absent 5 Pink sugarcane Saccharicoccus Light pink in color 92 countries and Sugarcane, reeds, some grasses etc. mealybug sacchari 10 states in India. 6 Pineapple Dysmicoccus 17 - 18 pairs of wax 113 countries and Pineapple, citrus, capsicum, coffee, mealybug brevipes filaments present 11 states in India. ficus, hibiscus, banana, potato, clove, cocoa, maize, ginger, grapes etc. 7 Hibiscus Maconellicoccus Pink to orange in 105 countries and Hibiscus, acalypha, acacia, mealybug hirsutus color, Produce red 15 states in India. asparagus, cabbage, cauliflower, (Phenacoccus to pink fluid when banyan, Fig, rubber plant, cotton, hirsutus) squashed. sunflower, jasmine, sapota, guava etc. 8 Mango Mealybug Drosicha flat shape body 4 countries and 5 Mango, neem tree, navel orange, mangiferae covered with white states in India. sweet potato, bottle guard, lantana, mealy powder tobacco, black night shade etc. 9 Cotton mealybug Phenacoccus Two dark brown 51 countries and Cotton, apple of sodom, Indian Solenopsis stripes on dorsum 15 states in India. laburnum, watermelon, bermuda with small thick wax grass, carrot, pepper mint, date- filaments palm etc.

Sl. No. Common name Scientific name Scientific name Scientific name Scientific name 10 Papaya Paracoccus Female has eight 55 countries and Papaya, cashew nut, pine apple, mealybug marginatus antennal segments 13 states in India. jatropha, banana, beans, cowpea etc. 11 Rice mealybug Brevennia rehi Pink in color, less 21 countries and Rice and other grasses than 2mm in size 9 states in India.

Solanum mealybug, Phenacoccus solani Ferris is almost a major pest of cotton, severely reducing (by around 35%) recorded to infest all the solanaceous crops. It looks similar yields (Figure 1i). to Phenacoccus solenopsis but lacks quinquelocular pores Papaya mealybug, Paracoccus marginatus Williams and (Figure 1d). Pink sugarcane mealybug, Saccharicoccus sacchari Granara de Willink is a severe pest of papaya in Tamil Cockerell is recorded from all sugarcane growing areas of India Nadu, India during 2006. The pest is being controlled by and found to cause poor germination and sugar loss. The juices its imported parasitoids from Puerto Rico in 2010. The from the infested crops were recorded to have loss of sucrose three parasitoids namely, Acerophagus papayae Noyes content and reduced purity percent (Figure 1e). Pineapple Pseudleptomastix mexicana mealybug, Dysmicoccus brevipes Cockerell has a pantropical and Schauff Noyes and Schauff distribution around the world. It is a major pest of pineapple and Anagyrus loecki Noyes and Menezes (Hymenoptera: causing 35% yield loss to the crop (Figure 1f). Encyrtidae) managed the pest within five months and the economic benefit due to use of parasitoids against the pest Hibiscus mealybug, Maconellicoccus hirsutus Green in different crops was over 800 crores. In a period of five (Phenacoccus hirsutus) cause damage to woody plants years the economic benefit was around 3000 crores (Figure including ornamentals. Severe infestation on susceptible 1j). Rice mealybug, Brevennia rehi Lindinger is the pest in rice plants can even cause death of the plants. In India it is found to cause economic damage to the crops such as cotton, growing states such as West Bengal, Orissa, Bihar, Andhra grapevines, pigeon peas and many fiber crops (Figure 1g). Pradesh, Tamil Nadu, Karnataka, Kerala and Maharashtra. Its Mango Mealybug, Drosicha mangiferae Green is an important infestation along with drought conditions may cause complete pest of mango which causes damage of 50% to mango fruits. It crop loss (Figure 1k). Several studies reveal the distribution has a peculiar flattened body shape with white mealy coating of pseudococcids was recorded around 180 countries among (Figure 1h). Cotton mealybug,Phenacoccus solenopsis Tinsley, 195 in the world. It has been reported from over 200 hosts recently invaded the Indian subcontinent, where it has become (CABI, 2021).

(a): Pseudococcus longispinus (b): Ferrisia virgata (c): Planococcus citri

(d): Phenacoccus solani (e): Saccharicoccus sacchari (f): Dysmicoccus brevipes

(g): Maconellicoccus hirsutus (h):Drosicha mangiferae (i): Phenacoccus solenopsis

(j): Paracoccus marginatus (k): Brevennia rehi Figure 1: Different species of mealybugs Mode of Dispersal and Spread he primary mode of dispersal from infested plants to healthy plants occurs by crawling and also carried Tby wind, water and rain. The mutual association of mealybugs with ants helps them in transport as ants carry them from one plant to another. Ants not only help in transport but also prevent the mealybugs from their natural enemies. Apart from ants, humans, birds, farm equipment’s aid in their transport. Long distance spread of the pest occurs through carrying infested plant parts such as fruits, vegetables, flowers and planting materials etc. Life Cycle of Mealybugs ost of them are parthenogenetic, some reproduce sexually (e.g. M. hirsutus). They were generally Figure 2: General life cycle of mealybug Mfound in clusters mostly in the plant canopy and Symptoms of Damage also in other parts. An egg sac may contain up to 600 eggs. There were three nymphal stages in females and four in males. ellowing and pre-matured fall of buds and young fruits They reproduce throughout the year if warm climate prevails can be noticed in fruit crops. Under severe infestation (Figure 2). Ythe plants can be noticed withcomplete defoliation and

even death. Mealybugs feed canopy stops growth that results by Dysmicoccus brevipes. The symptoms such as reddening in stunted growth of the plants (Tanwar et al., 2007). Their of leaves, leaf tip dieback, downward curling of leaf margins honey dew secretions invite sooty mould that reduces the will be noticed. Tukra disease of mulberry was caused by photosynthesis. In flowering plants clusters of nymphs and Maconellicoccus hirsutus and Paracoccus marginatus (Table adults in the flowers affects their development. 2). The disease also affected the silk production by making poor quality feeds to the silkworm. Cocoa swollen shoot virus Vector of Diseases was transmitted by different species of mealybugs especially he feeding habit of mealybug has an intimate relationship by Dysmicoccus brevipes. Symptoms of the disease are vein with virus transmission. Grapevine leaf roll virus (GLRV clearing and rarely fernlike patterns. Little cherry disease was - Ampelovirus) was transmitted by Planococcus citri. transmittedPhenacoccus sp. Its infestation leads to tasteless T cherry production. Pineapple wilt of mealybug was semi-persistently transmitted

Table 2: Disease transmitted by mealybugs Sl. No. Disease Vector Crop Yield loss to the crop 1 Leaf roll virus Planococcus citri Grapevine Up to 40% 2 Wilt Dysmicoccus brevipes Pineapple Around 30 – 35% 3 Tukra disease Maconellicoccus hirsutus and Mulberry Up to 35% Paracoccus marginatus 4 Swollen shoot virus Dysmicoccus brevipes Cocoa Around 15-50%, on severe infestation complete loss can be noticed. 5 Little cherry disease Phenacoccus sp. Cherry On severe damage cause complete yield loss. 6 Badna virus Ferrisia virgata cocoa and black Up to 15% diseases pepper Integrated Pest Management Nephus regularis, Scymnus coccivora and Rodolia fumida can be augmented and conserved. Strategies • The predatory beetles can be recommended at the rate of Cultural Control 5000 beetles/ha released one to three times depending on the crop ecosystem and severity of damage. For tree crops, • Under initial stages of infestation strong jet of water can be 10 beetles/tree can be released. applied to remove bugs from the infested parts. • Spraying Verticillium. lecanii or Beauveria. bassiana (2 × 108 • Controlling ant’s population through ant fence around the cfu/ml) can be advised during high humid months in reducing field can be used to reduce mealybug dispersal. the population of mealybugs. • The infested plant parts should be destroyed. Chemical Control • Weeds around the field should be maintained clean to arrest • Pesticides safer to natural enemies can be utilized. To reduce the spreading of mealybug. ant population Chlorpyriphos 20 EC @ 2.5 ml/l or apply 5% • Farm machineries, tools and equipment’s should be sanitized Malathion dust @ 25 kg/ha can be drenched. instantaneously to avoid the secondary infestation. • Since mealybugs naturally have much greater protection • In perennial crops, population behind the barks should be against contact pesticides by means of hiding in crevices and wiped out or the stem should be swabbed with dichlorvos 76 having waxy coating, systemic chemicals can be preferred EC @ 2 ml + 2 g of fish oil resin soap in a litre of water. comparably. Biological Control • Use any of the insecticides or botanical - Neem oil @ 30 ml/lit, Imidacloprid 200 SL @ 1 ml/l, Malathion 50 EC @ 2 • Biological control agents such as Cryptolaemus montrouzieri ml/l, Dimethoate 30 EC @ 2 ml/l, Methyl demeton 25 EC @ (Australian lady bird beetle), Anagyrus pseudococci, Hypoaspis 2 ml/l, Phosphamidon 40 SL @ 1.25 ml/l, Monocrotophos 36 sp., Leptomastix dactylopii, Verticillium lecanii and Beauveria WSC @ 2 ml/l. bassiana can be used to manage mealy bugs. Laelapid mite, Hypoaspis feeds on crawlers. Biotechnological Approaches • Predators of mealybugs such as Cheilomenes sexmaculata, • RNA interference of two genes, Bursicon (PsBur) and

V-ATPase (PsV-ATPase) can be used to control Phenacoccus References solenopsis. Nicotiana tabacum plants expressing these two genes reduced the population of mealybugs (Arifet al., 2018). Arif, M.K., Muhammad, A., Azhar, A.K., Muhammad, Nanotechnology in Pest Management T.N., Shahid, M., 2018. Evaluation of potential RNA- interference-target genes to control cotton mealybug, • Silver nanoparticles of ginger extract recorded to cause Phenacoccus solenopsis nd rd (Hemiptera: Pseudococcuidae). mortality of 2 and 3 instars of Planococcus citri. Insect Science 25(5), 778-786. doi: 10.1111/1744- Conclusion 7917.12455. CABI, 2021. Invasive Species Compendium. Detailed coverage hanging environmental conditions put biologist and of invasive species threatening livelihoods and the ecologist in vigilant action for careful monitoring of environment worldwide (Retrived on 07.03.2021). Cecological parameters. Insect pests are one organism https://www.cabi.org/isc/datasheet/45078 can easily invade, adopt in different agro-ecosystems. Tanwar, R.K., Jeyakumar, P., Monga, D., 2007. Mealybugs and Management of these types of pests such as mealybugs their management. National Centre for Integrated Pest required specific attention on detailed studies on pest Management, New Delhi, 110(12), 1-10. identification, distribution, life cycle and its expression of symptom. More studies on this type of invasive and minor insects are needed to be focused in future to counteract their attack on crop plants.