1. A REVIEW ON BIOLOGY AND
MANAGEMENT OF MAIZE STEM BORER,
Chilo partellus (Swinhoe, 1885)
PRESENTER:
Madan Subedi
Msc.Ag. Entomology
Roll no. R-2018-ENT-01M
Agriculture and Forestry University

2. INTRODUCTION
• One of the most severe insect pests of maize in Nepal (Neupane, 1986)
• Damage results dead heart which in extreme case renders the plant
earless (Neupane, Bhandari, Sharma, Yadav, & Subedi, 2016)
• Cause loss range from 20-80% in maize (Thakur, Shrestha, Bhandari, &
Achhami, 2013)
• A total of 28% more harvest from uninfested fields as compared to
the fields infested with maize stem borer (Sharma & Gautam, 2010)

3. SCIENTIFIC CLASSIFICATION
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Lepidoptera
Super-family: Pyraloidea
Family: Crambidae
Sub-family: Crambinae
Genus: Chilo
Species: C. partellus
Binomial name: Chilo partellus (Swinhoe, 1885)

4. GEOGRAPHICAL DISTRIBUTION
 Native to Asia (Kalaisekar, Padmaja, Bhagwat, & Patil, 2017)
 First recorded in Africa from Malawi in 1932 (Tams, 1932)
 Currently, widespread in Asia and Africa (Bleszynski, 1970; Jepson, 1954;
Panwar, 2005; Sallam & Allsopp, 2008; Sharma, Kumar, & Sharma, 2006)
 Dominant and economically most important stem borer species at
elevations below 1800 m in Africa (Seshu, 1983)
 Evidences of displacement of Chilo orichalcociliellus (Strand) by Chilo
partellus in Africa (Ofomata, Overholt, Lux, Huis, & Egwuatu, 2000)

5. IDENTIFICATION
Eggs
 Shape: flat and oval (scale-like)
 Colour: creamy-white
 Size: about 0.8mm long
 Form of appearance: Overlapping batches of 10-80 eggs
Fig. Egg batch of Chilo partellus

6. ……IDENTIFICATION
Larva
 Have only 4 pinkish stripes, the median stripe being absent, the lateral
stripes passing above the abdominal spiracles
Fig. Chilo partellus larva

7. ……IDENTIFICATION
….Larva
 Arrangement of seta and tubercles
Fig. Setal arrangement in thorax Fig. Setal arrangement in abdominal Fig. Setal arrangement in
(meso and metathorax) segment (1-7) eight abdominal segment

8. ……IDENTIFICATION
….Larva
Fig. Chaetotaxy of the head of Chilo partellus

9. ……IDENTIFICATION
Pupa
Fig. Lateral view of pupa Fig. Arrangement of spines on the dorsum
of 5th abdominal segment of the pupa

10. ……IDENTIFICATION
….Pupa
Fig. Dorsal and ventral views of the cremaster of the pupa of Chilo partellus

11. ……IDENTIFICATION
….Pupa
Fig. Pupa of Chilo partellus

12. ….IDENTIFICATION
Adult
Fig. Adult Chilo partellus

13. ….IDENTIFICATION
….Adult
Fig. Forewing of Chilo partellus Fig. Hindwing of Chilo partellus

14. LIFE CYCLE
 Eggs laid in batches on both host and non-host plants (10-80 per batch)
 Freshly hatched larva search for host plants
 Leaves enclosed in whorl – preferred by larva
 Larva use mechanism of ballooning/walking for movement (Berger,
1992)
 Larva undergoes 6 instars molting 5 times (Patel, Devananda, & Korak,
2018)
 Pupation- Inside larval tunnel or outside plant (exit holes are evident)
(Achhami, BK, & Bhandari, 2015)
 Most favourable temperature for development: 30 0C
 5 generations per year in Chitwan conditions (Neupane, Chapman, &
Coppel, 1986)

15. ….LIFE CYCLE
Fig. Summary of life cycle of Chilo partellus (Source: Magara, 2016)

16. NATURE OF DAMAGE
Leaves enclosed in whorls- damaged by scrapping by early instar
larva
Symptoms evident as symmetrical holes when leaves come out of
whorl (Reddy, 1998)
Two types of holes:
Pin holes (small, pin head size)
Window panes (large than pin head, leaves tend to tear apart)
Dead heart- Central leaves damaged and growing points killed
Late instar larvae- Move to collar region, develop feeding tunnels
Entry of larva in cobs damage grains

17. ….NATURE OF DAMAGE
Overall effect on plant- Poor growth and reduced yield
Infested plants- Highly susceptible to wind damage and secondary
infections (Berger, 1989)
Damage to crop stages (Fletcher & Ghosh, 1920)
100% damage may take place at early stage
Matured plants show some degree of tolerance

18. ….NATURE OF DAMAGE
Fig. Larval tunnel
Fig. Larval tunnel
Fig. Dead heart Fig. Pin holes Fig. Window panes

19. HOST PLANTS
Primary host plants (Bleszynski, 1970)
 Zea mays (Maize)
Sorghum bicolor (Sorghum)
Oryza sativa (Rice)
 Saccharum officinarum (Sugarcane)
Other host plants (CABI, 2007; Kfir, Overholt, Khan, & Polaszek, 2002)
Pennisetum glaucum (Pearl millet)
Sorghum vulgare sudanense (Sudan grass)
Pennisetum purpureum (Napier grass)

20. DIAPAUSE
Facultative diapause is reported in C. partellus
Summer diapause (Scheltes, 1978)
Winter diapause (Dhillon & Hasan, 2017)

21. ….DIAPAUSE
(Source: Dhillon & Hasan, 2017)
Characteristics Non-diapause Diapause (Aestivation/Hibernation)
Size of larvae Large Reduced
Body colour and pigmentation Light brown with dark brown
pigmentation
Creamy to milky white with reduced or
no pigmentation
Asetose tubercles (AT) Present Absent
Head capsule colour Dark brown to black with clear
epicranial suture
Reddish brown sometime with distinct
epicranial suture
Color of prothorasic shield Dark brown Light brown to creamy
Symptoms to enter diapause (diapause
chamber)
No diapause chamber Fail to pupate and construct diapause
chamber
Supernumerary moults No supernumerary moults >2 supernumerary moults
Pupal size Larger Smaller
Adult colour and size Light brown and larger in size Dark brown and smaller in size

22. ECONOMIC INJURY LEVEL (EIL)
EIL - insect pest abundance or amount of damage that results in
economic yield loss (Pedigo, 1991)
Most vulnerable period for borer attack: 10-17 days (Sarup et al.,
1977)
EIL for kharif and rabi maize - 2.42 and 2.09 larvae per plant
(Chouraddi & Mallapur, 2017)
EIL for 20- and 40-day old plants- 3.2 and 3.9 larvae/plant (Reddy &
Sum, 1991)
EIL for insecticidal application - 20% and 2% of plants with visible
symptoms of whorl damage, for the resistant and susceptible
genotypes (Berg, Rensburg, & Westhuizen, 1997)

23. MANAGEMENT PRACTICES

24. Cultural control
Good crop hygiene
Destruction of crop residues (stems and stubbles)
Removal of volunteer crop plants and/or alternative hosts of
diapausing larvae and active populations (Verma & Singh, 1989)
Intercropping of maize with cowpea in the ratio 1:1 (Singh, Jaglan, &
Verma, 2018)

25. Biological control
Biological control agents - Cheap and effective ( Kfir, 1992)
Spinosad 45% EC prepared from bacteria Saccharopolyspora spinosa
(Neupane et al.,2016; Devanapalli & Kumar, 2018)
Beauvaria bassiana- an effective fungus (Maniania, 1993)
Formulations of the protozoan Nosema marucae and Nosema partelli
(Odindo & Opondo, 2009; Walter & Kfir, 1993)
Commercial preparations of bacterium Bacillus thuringiensis
(Brownbridge, 2001)

26. ….Biological control
Table 2. Common parasitoids used for management of MSB (Kfir, 1997)
Parasitoid Order Family
Allorhogas pyralophagus Hymenoptera Braconidae
Cotesia chilonis Hymenoptera Braconidae
Cotesia flavipes Hymenoptera Braconidae
Descampsina sesamlae Diptera Tachinidae
Mallochia pyralidi Hymenoptera Ichneumonidae
Meloboris sinicus Hymenoptera Ichneumonidae
Metagonistylum minense Diptera Tachinidae
Paratheresia claripalpis Diptera Tachinidae
Sturmiopsis inferens Diptera Tachinidae
Tetrastichus howardi Hymenoptera Eulophidae
Trichogramma chilonis Hymenoptera Trichogrammatidae
Trichogramma ostrinia Hymenoptera Trichogrammatidae
Xanthopimpia stemmator Hymenoptera Ichneumonidae

27.  Pheromonal control
 Mating disruption preferred to mass trapping (Campion & Nesbitt,
1983)
Major chemical components of pheromone (Hansson, Blackwell,
Hallberg, & Lofqvist, 1995)
• Z)-11-hexadecenal
• (Z)-11-hexadecenol
• (Z)-10-pentadecenal

28. Botanical control
 Methanolic extracts of Bougainvillea spectabilis flowers and distilled
water leaf extracts of Nerium oleander (Anuj & Sharma, 1999)
Chloroform and methanol leaf extracts of Cymbopogon martinii and
Eucalyptus globulus kill larvae up to 5 days after treatment (Bhatnagar
& Sharma, 1999)
Extracts from Azadirachta indica and Annona squamosa kernels
(Sharma, Sankaram, & Nwanze,1999)

29. Chemical control
Timing of application of chemical insecticides is crucial (Nwanze &
Mueller, 1967)
Effective in early growth stage of the crop (i.e. up to 10 ± 12 days)
Best when applied at egg hatching and the first three instars, before
the larvae enter the stem
Organochlorines, organophosphates, carbamates and synthetic
pyrethroids - widely used against the pest (Dharmasena, 1993; Teli,
Chavan, Ankalkoppe, Khot, & Harers, 2007)
Chloropyrifos 10% EC @ 1.5 ml L-1 of water, chloropyriphos 50%
EC+cypermethrin 5% EC @ 1.5 ml L-1 of water, imidachloprid 17.8%
@ 0.5 ml L-1 of water commonly used in Nepal (Neupane et al., 2016)