Abstract
In teak plantations at Nilambur, Kerala,Hyblaea puera Cramer (Lepidoptera, Hyblaeidae) caused one or two waves of epidemic defoliations between late April and July, followed in some years by isolated, lighter defoliation between August and November. The insect was absent at other periods, although with a 3-week life cycle it can theoretically pass through several generations per year. The temporal and spatial distribution of infestation and certain behavioural characteristics of populations gave evidence of short-range migration of newly emerged moths. In a model proposed for population dynamics ofH. puera, no diapause occurs and a residual, non-migratory population exists in natural forests during the nonepidemic period. With the onset of general flushing of teak in February–March, the population starts building up and when a critical density is reached, migratory behaviour is triggered. Migration facilitates exploitation of new food sources and escape from larval parasites. Generally, after one or two epidemics, the population declines due to leaf maturity, natural enemies and density-dependent food depletion. This cycle of ups and downs, with attendant transition between migratory and non-migratory phases is repeated every year. If some steps of the proposed model are confirmed by further study, simple methods could be devised to manage this serious pest of teak.
Similar content being viewed by others
References
Beeson C F C 1928 The defoliation of teak;Indian For 54 204–215
Beeson C F C 1941The ecology and control of the Forest Insects of India and the neighbouring countries (New Delhi: Govt. of India) (1961 Reprint) p. 767
Chatterjee S N 1932 Identification of teak defoliators in the field;Indian For.58 689–691
Chatterjee P N and Misra M P 1974 Natural insect enemy and plant host complex of forest insect pests of Indian region.Indian For. Bull. 265 233
Nair K S S 1980 The problem of insect defoliation of teak-to spray or not to spray;Proc. 2nd Forestry Conf., Dehra Dun, India, p. 7
Riley J R, Reynolds D R and Farmery M J 1983 Observations of the flight behaviour of the armyworm moth,Spodoptera exempta, at an emergence site using radar and infra-red optical techniques.Ecol. Entomol. 8 395–418
Rose D J W, Page W W, Dewhurst C F, Riley J R, Reynolds D R and Pedgley D E 1983 TDRI-DLCOEA-KARI African Armyworm Project 2. Recent studies on migration;Proc. 10th Internat. Congr. Plant Prot. 1 181 (Croydon, UK: British Crop Protection Council)
Singh P 1980 Aerial spraying of chemicals to control teak defoliators;Proc. 2nd Forestry Conf., Dehra Dun, India, p. 9
Vaishampayan S M and Bahadur A 1983 Seasonal activity of adults of teak defoliatorHyblaea puera and teak skeletonizerPyrausta machaeralis (Pyralidae: Lepidoptera) monitored by light trap catch; inInsect Interrelations in Forest and Agro-Ecosystems (eds) P K Sen-Sarma, S K Kulshresstha and S K Sangal (Dehra Dun: Jugal Kishore and Co.) pp. 137–146
Vaishampayan S M, Verma R and Nema K K 1984 Reproductive analysis of light trap catches of teak defoliatorsHyblaea puera Cramer (Lepidop: Hyblaeidae) at Jabalpur; inAbstracts of Third Oriental Entomology Symposium Feb 1984 p. 64 (Abstract only) (Trivandrum: Association for Advancement of Entomology)
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Nair, K.S.S., Sudheendrakumar, V.V. The teak defoliator,Hyblaea puera: Defoliation dynamics and evidences for short-range migration of moths. Proc. Indian Acad. Sci. (Anim. Sci.) 95, 7–21 (1986). https://doi.org/10.1007/BF03179354
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF03179354