Tobacco budworm Spodoptera litura (Fabricius) Lepidoptera:Noctuidae

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Islamic Republic Of Iran Ministry of Jihad-e-Agriculture Plant Protection Organization A Guide for Diagnosis & Detection Of Quarantine Pests Tobacco

1 Islamic Republic Of Iran Ministry of Jihad-e-Agriculture Plant Protection Organization A Guide for Diagnosis & Detection Of Quarantine Pests Tobacco budworm Spodoptera litura (Fabricius) Lepidoptera:Noctuidae Edited by: Ahmad cheraghian Bureau of Plant Pest Surveillance and Pest Risk Analysis 2014

2 Spodoptera litura (Fabricius) Lepidoptera: Noctuidae Common name: Taro caterpillar, tobacco budworm, cotton leafworm, Tobacco cutworm, Egyptian cotton leaf worm, cluster caterpillar, rice cutworm, Tobacco caterpillar, tobacco leaf caterpillar, common cutworm, cotton worm, armyworm, Synonyms: Prodenia litura Fabricius, Mamestra albisparsa Walker Prodenia ciligera Guenée, Prodenia declinata Walker Noctua elata Fabricius, Prodenia evanescens Butler Prodenia glaucistriga Walker, Noctua histrionica Fabricius Prodenia subterminalis Walker, Prodenia tasmanica Guenée Noctua litura Fabricius, Prodenia testaceoides Walker Prodenia littoralis Fabricius Economic impact: S. litura larvae are polyphagous defoliators, seasonally common in annual and perennial agricultural systems in tropical and temperate Asia. This noctuid is often found as part of a complex of lepidopteran and non-lepidopteran foliar feeders but may also damage tubers and roots. Hosts include field crops grown for food and fibre, plantation and forestry crops, as well as certain weed species. Most work on the economic impact of S. litura has been conducted in India where it is a serious pest of a range of field crops. It has caused 12-23% damage to tomatoes in the monsoon season, and 9-24% damage in the winter (Patnaik, 1998). In a 40- to 45- day-old potato crop, damage ranged from 20 to 100% in different parts of the field depending on moisture availability. Larval populations peaked at four fully-grown larvae per square metre when the crop was days old. Larvae also attacked exposed tubers when young succulent leaves were unavailable. Up to 2% of tubers were damaged in August-September and February (Trivedi, 1988). S. litura is also a pest of sugarbeet, with infestations commencing in March and peaking in late March and April (Chatterjee and Nayak, 1987). Severe infestations led to skeletonisation of leaves as well as feeding holes in roots that rendered the crop 'virtually unfit for marketing'. Late harvested crops were most severely affected and, in extreme cases, 100% of the roots were damaged, leading to 'considerable' yield reduction. Work on this species in a complex of other sugarbeet defoliators (Spodoptera exigua and Spilosoma obliqua) led to the development of an interactive exponential model based on length and severity of defoliation. It explained 88-90% of the variability in root and sugar yields and suggested the need for pest control when defoliation exceeded 25% during April. Control was not required if the pest appeared after the first week of May (Singh and Sethi, 1993). S. litura is one of six defoliating pests of fodder cowpea which, in a field experiment, were responsible for consuming up to 85.5% of leaf area (Ram et al., 1989). Aroid tuber crops (including taro (Colocasia esculenta)) suffered yield losses of up to 29% as a result of infestation by S. litura, Aphis gossypii and spider mites (Pillai et al., 1993). S. litura is also a member of a complex that causes extensive defoliation of soyabean (Bhattacharjee and Ghude, 1985). Defoliation as severe as 48.7% during the pre-bloom stage of growth caused no 'marked' difference from a control treatment in which defoliation was prevented by repeated insecticide application. Number and

3 weight of pods and grains per plant were, however, reduced when defoliation occurred at, or after, blooming. In groundnut, S. litura is one of several pests that can be important during the pegging, podding and pod maturation stages of growth (Singh and Sachan, 1992). Several studies have aimed at quantifying the damage attributable to S. litura. Field experiments by Panchabhavi and Raj (1987) extended over 2 years and used artificial infestation of groundnut plots of 15 m² with differing densities of S. litura. Infestation levels of just three egg masses (of 250 eggs each) caused significant loss of groundnut pods and haulms. Infestation with 12 egg masses per plot led to a haulm yield reduction of up to 43.7% and a pod yield reduction as high as 27% compared with an insecticide-protected control treatment. In other field experiments over 3 consecutive years, leaf damage attributed to S. litura tended to decline with delayed sowing time irrespective of groundnut cultivar (Patil et al., 1996). Leaf damage fell from 51.8% for mid-june sown crops to 19.2% for late-july sown crops. Mean pod yields were 2.68 and 0.99 t/ha, respectively. Another field study determined the effect of artificially infesting individual groundnut plants with third-instar S. litura larvae 15, 30 or 45 days after emergence (d.a.e.) (Dhir et al., 1992). The most severe damage occurred when plants were infested with three larvae 15 d.a.e. These lost 98.3% of leaf area, and pod yield was reduced by 50%. Even single larvae caused the leaf area to be more than halved and pod yield to fall by 27.3%. Plants infested 30 d.a.e. suffered similar levels of damage but those infested 45 d.a.e. were less severely affected. S. litura causes damage to many species of forest and plantation trees and shrubs (Roychoudhury et al., 1995). It is responsible for brown flag syndrome in banana (Ranjith et al., 1997), and 5-10% fruit damage in grapes (Balikai et al., 1999). In Paulownia nurseries and plantations a complex of at least 24 defoliating pest species causes damage. Within this complex, S. litura was considered the most important noctuid species, with an incidence of 72% in weekly surveys (Kumar and Ahmad, 1998). Peak activity occurred in July and September, with an average of 6.5 and 5.2 larvae per plant in these months, respectively. During this period, many plants were completely defoliated by S. litura. In teak, it is one of about 139 defoliators that attack all stages from seedlings to mature trees (Roychoudhury et al., 1995). S. litura is abundant on teak in June and July and damage incidence in seedlings has been reported to be as high as 56%. Late-instar larvae were found to feed preferentially on mature teak leaves, whilst early instars fed on leaves of intermediate age. High concentrations of polyphenols in young leaves (Roychoudhury et al., 1995) may reduce their attractiveness to S. litura larvae but differing levels of susceptibility among nine teak clones were attributed to the nitrogen:potassium ratio of the foliage (Roychoudhury et al., 1998). Studies elsewhere in southern Asia illustrate the economic impact of S. litura. In Pakistan, it is one of several lepidopteran pests attacking a wide range of crops including cotton and rice (Ahmad and Kamaluddin, 1987), as well as cabbage, tobacco, groundnut, soyabean, lucerne, gram, cowpea, tomato, cauliflower, carrot, onion, brinjal, turnip, radish and spinach (Maree et al., 1999). In the latter study, S. litura was present in a December-planted cabbage crop during January-March with densities peaking at 4.55/plant on 2 February. Damage was highest in early February and there was a positive correlation between plant damage and pest density. Fieldwork in Bangladesh led to a 10% visual damage spraying threshold being proposed for S. litura and Plutella xylostella (Ali and Bakshi, 1994).

4 In eastern Asia, damage by S. litura occurs as far north as Japan, extending south to Indonesia. Japanese soyabean field plots artificially infested with one or two S. litura egg masses per plant suffered estimated leaf area reductions of 14.3 and 23.2% and yield losses of 13.9 and 24.7%, respectively, compared with control plots (Higuchi et al., 1994). Similar work indicated that yield losses caused by early infestation (at the flowering and pod-development stages) were attributable chiefly to reduced production of pods per plant, whilst infestations on more mature plants affected yield by reducing the weight of individual beans (Higuchi, 1991). In studies with red (adzuki) bean, the effect of defoliation by S. litura on yield was investigated by artificial defoliation. Combined with observations that the average leaf area consumed by S. litura was cm², of which 82% was consumed by final-instar larvae, an action threshold of two final-instar larvae/plant (causing 5% yield loss) was estimated (Katayama and Sano, 1989). Equivalent thresholds were developed for protected crops in Korea (Nakasuji and Matsuzaki, 1977). In this instance, a 10% yield loss threshold was applied and the threshold densities of S. litura were 4.6 and 15.4 neonates or 0.8 and 2.6 egg masses/m², for aubergine and sweet peppers, respectively. S. litura is also found in Welsh onion crops in Korea, but is less damaging than other lepidopterans such as Liriomyza chinensis (Ahn et al., 1991). Hosts: The host range of S. litura covers at least 120 species. Among the main crop species attacked by S. litura in the tropics are Colocasia esculenta, cotton, flax, groundnuts, jute, lucerne, maize, rice, soyabeans, tea, tobacco, vegetables (aubergines, Brassica, Capsicum, cucurbit vegetables, Phaseolus, potatoes, sweet potatoes and species of Vigna). Other hosts include ornamentals, wild plants, weeds and shade trees (for example, Leucaena leucocephala, the shade tree of cocoa plantations in Indonesia). Major hosts:abelmoschus esculentus (okra), Acacia mangium (brown salwood), Allium cepa (onion), Amaranthus (grain amaranth), Arachis hypogaea (groundnut), Beta vulgaris var. saccharifera (sugarbeet), Boehmeria nivea (ramie), Brassica, Brassica oleracea var. botrytis (cauliflower), Brassica oleracea var. capitata (cabbage), Camellia sinensis (tea), Capsicum frutescens (chilli), Cicer arietinum (chickpea), Citrus, Coffea (coffee), Colocasia esculenta (taro), Corchorus (jutes), Corchorus olitorius (jute), Coriandrum sativum (coriander), Crotalaria juncea (sunn hemp), Cynara, Cynara cardunculus L. var. scolymus (globe artichoke), Fabaceae (leguminous plants), Foeniculum vulgare (fennel), Fragaria ananassa (strawberry), Gladiolus hybrids (sword lily), Glycine max (soyabean), Gossypium (cotton), Gossypium hirsutum (Bourbon cotton), Helianthus annuus (sunflower), Hevea brasiliensis (rubber), Ipomoea aquatica (swamp morning-glory), Ipomoea batatas (sweet potato), Jatropha curcas (Barbados nut), Lathyrus odoratus (sweet pea), Lilium (lily), Linum usitatissimum (flax), Lycopersicon esculentum (tomato), Malus domestica (apple), Manihot esculenta (cassava), Medicago sativa (lucerne), Morus alba (mora), Musa (banana), Nicotiana tabacum (tobacco), Oryza sativa (rice), Papaver (poppies), Paulownia tomentosa (paulownia), Phaseolus (beans), Piper nigrum (black pepper), Poaceae (grasses), Polyphagous (polyphagous), Psophocarpus tetragonolobus (winged bean), Raphanus sativus (radish), Ricinus communis (castor bean), Rosa (roses), Sesbania grandiflora (agati), Solanum melongena (aubergine), Solanum tuberosum (potato), Sorghum bicolor (sorghum), Syzygium aromaticum (clove), Tectona grandis (teak), Theobroma cacao (cocoa), Trigonella foenum-graecum (fenugreek), Vigna mungo (black gram), Vigna radiata (mung bean), Vigna unguiculata (cowpea), Vitis vinifera (grapevine), Zea mays (maize), Zinnia elegans (zinnia)

Geographic distribution: Asia: Afghanistan, Bangladesh, Brunei, Cambodia, China, Taiwan, India, Indonesia, Japan, Korea DPR, Korea Republic of,laos, Malaysia, Maldives, Myanmar, Nepal, Oman,

5 Geographic distribution: Asia: Afghanistan, Bangladesh, Brunei, Cambodia, China, Taiwan, India, Indonesia, Japan, Korea DPR, Korea Republic of,laos, Malaysia, Maldives, Myanmar, Nepal, Oman, Pakistan, Philippine, Singapore, Sri Lanka, Thailand, Vietnam, Africa: Réunion Europe:USSR North America: USA Australia and Pacific Island:, American Samoa, Australia, Belau, Caroline Islands, Cook Islands, Federated states of Micronesia, Fiji, French Polynesia, Guam, Kiribati, Marshall Islands, New Zealand,, Papua New Guinea, Pitcairn Islands, Samoa, Solomon Islands, Tonga, Tuvalu, Midway Islands, Vanuatu,. World distribution map of Spodoptera litura Morphology: Eggs Spherical, somewhat flattened, 0.6 mm in diameter, laid in batches and covered with hair scales from the tip of the abdomen of the female moth. Usually pale orange-brown or pink in colour. Egg masses measure about 4-7 mm in diameter and appear golden brown because they are covered with body scales of females. Larva Larva hairless, variable in colour (young larvae are light green, the later instars are dark green to brown on their backs, lighter underneath); sides of body with dark and light longitudinal bands; dorsal side with two dark semilunar spots laterally on each segment, except for the prothorax; spots on the first and eighth abdominal segments larger than others, interrupting the lateral lines on the first segment. Though the markings are variable, a bright-yellow stripe along the length of the dorsal surface is characteristic of S. litura larvae. Larval instars can be distinguished based on head capsule width ranging from 2.7 to 25 mm, and body length ranges from 2.3 to 32 mm. Pupa mm long, red-brown; tip of abdomen with two small spines. Adult Moth, with grey-brown body, mm long; wingspan mm. The forewings are grey to reddish-brown with a strongly variegated pattern and paler lines along the veins (in males, bluish areas occur on the wing base and tip); the hindwings are greyish-white with grey margins, often with dark veins in S. litura (but without in S. littoralis). See also Schmutterer (1969), Cayrol (1972), and Brown and Dewhurst (1975).

6 Eggs of Spodoptera litura

7 Young larva, feeding on Banana leaf;length was 8.3 mm / 0.3 inch. Nov 18, The 2nd larva on Nov 12, 2001; Length was 1.5 cm / 0.6 inch. Nearly mature larva, about 3.2 cm / 1.3 inches long. Nov 19, Final instar larva; Dec 1, The coiled shape is typical of cutworms when disturbed. Larva of Spodoptera litura

The pupa was formed on Dec 16, 1999 and Nov 25, 2001.

8 The pupa was formed on Dec 16, 1999 and Nov 25, Note the thoracical, ventral knobs Pupa of Spodoptera litura

9 Moth in rest posture. Eclosure was on Dec 21, 1999 and Dec 10, Top and bottom views of the moth. The wingspan was about 3.5 cm / 1.4 inches Adult of Spodoptera litura

10 Adult of Spodoptera litura

litura are 64 day degrees above threshold 8 C, from oviposition to egg hatch, the larval period required 303 degree days and the pupal stage 155 degree days above a 10 C threshold.

12 Biology and ecology: S. litura eggs are laid in clusters of several hundreds, usually on the upper surface of the leaves. Fecundity varies from eggs, and oviposition days vary from 6 to 8 days. The developmental thresholds and thermal requirements for different stages of S. litura are 64 day degrees above threshold 8 C, from oviposition to egg hatch, the larval period required 303 degree days and the pupal stage 155 degree days above a 10 C threshold. The response of various stages of S. litura to temperatures under constant laboratory conditions was similar to that under field conditions. The upper development threshold temperature for all stages was 37 C, and 40 C was lethal (Ranga Rao et al., 1989). Eggs take 2-3 days to hatch, the larvae disperse quickly from the egg batch in groundnut. Newly hatched larvae can be detected by the 'scratch marks' they make on the leaf surface. The older larvae are night feeders and are usually found in the soil around the base of the plant during the daytime. They can chew large areas of leaf and at high population densities cause complete defoliation. The larvae can migrate in large groups from one field to another. In lighter soils, the larvae while hiding in the soil during daytime can also cause damage to groundnut pods. The larvae go through six instars and the final instars weigh up to 800 mg. Individual larvae can consume around 4 g fresh weight of groundnut foliage. However, 80% of the total consumption is in the final instar. Pupation takes place in the soil close to the plants. The pupal period lasts about 7-10 days. After adult emergence, peak oviposition occurs on the second night. Females mate three or four times during their lifetime, while males mate up to 10 times. In Andhra Pradesh, India, this species completes 12 generations a year, each lasting slightly more than a month in winter and less than a month in the hot season. Adult male (right) and female (left) moths. K. Kiritani (JP) Life cycle of Spodoptera litura

Symptoms: On most crops, damage arises from

bolls have large holes in them from which

brownish-red patches and the stem base may

13 Symptoms: On most crops, damage arises from extensive feeding by larvae, leading to complete stripping of the plants. On Cotton Leaves are heavily attacked and bolls have large holes in them from which yellowishgreen to dark-green larval excrement protrudes. On Tobacco Leaves develop irregular, brownish-red patches and the stem base may be gnawed off. On Maize The stems are often mined and young grains in the ear may be injured. Symptoms by affected plant part, Leaves: honeydew or sooty mould. Damage of Spodoptera litura

14 Damage of Spodoptera litura

different hosts (Salama and Shoukry, 1972).

In international trade, eggs or larvae may be

vegetables; for example, the introduction of S.

imported from Singapore (Aitkenhead et al.

15 Means of movement and dispersal: Adult dispersal The moths have a flight range of 1.5 km during a period of 4 h overnight, facilitating dispersion and oviposition on different hosts (Salama and Shoukry, 1972). They can accordingly fly quite long distances. In international trade, eggs or larvae may be present on planting material, cut flowers or vegetables; for example, the introduction of S. litura into the UK was on aquatic plants imported from Singapore (Aitkenhead et al., 1974). Phytosanitary significance: S. litura and are listed as of quarantine significance by Iran, EPPO, CPPC, NAPPO and OIRSA. Inspection host for Spodoptera litura

16 Detection and inspection Detection is facilitated by searching fields for leaf feeding damage and by pheromone traps. Z9, E11 14:Ac(A), Z9, E12 14:Ac(B), Z9 14:Ac(C) and E11 14:Ac(D). Detection and inspection host field for Spodoptera litura

17 References: Abai, M. (1984).List of forest trees and shrubs of Iran. Plant pests and Diseases Rech. Inst.,Tehran, 147p. Barouti,S.,A.alavi,2004,Plant Nematology,Principles, Parasitic and Quarantine Nematode in Iran., p. Behdad,E.,1984.Pests of Fruit Crops in Iran,Sepehr pub,tehran,822p. Esmaile,M.1983, Pests of Fruit Crops in Iran, Sepehr pub,tehran,366p. CAB International Crop Protection Compendium Edition. CAB International. Wallingford, Oxon, UK. Modarres Awal, M.2012.List of Agricultural pests and Their Natural Enemies in Iran. Revised Edition, Ferdowsi university Prss,778p. Salavatean, Mer.1996, Plant quarantine in Iran, Research Institute,Ministey of Agriculture pub,279p. ccs-hk.org/.../noctuid/spodoptera-litura.html en.wikipedia.org/wiki/file:spodoptera_litura lepidoptera.butterflyhouse.com.au/acro/litura... nanang.blog.unej.ac.id/ bioorganicsolutions.co.in/trap.htm en.wikipedia.org/wiki/spodoptera

Information sources: 10, 15, 16

Information sources: 10, 15, 16 1 There are two species of cotton leaf worm that are geographically isolated; S. litura and S. littoralis. S. litura is found in Asia while S. littoralis is primarily in Africa. Some literature cites the