Seasonal bionomics of Heliothis armigera (Hubner) (Lepidoptera: Noctuidae) in the Terai Belt of northeastern Uttar Pradesh

Abstract

bstract-Heliothis armigera (Hubner) completed five generations in the laboratory, as well as in the field, in a year. The first generation was completed from the first week of December to the fourth week of February, the second generation from the second week of February to first week of April. The third generation from third week of August passing through the extreme summer, the fourth generation during monsoon period and the fifth last generation from the third week of September to the fourth week of November. The seasonal variation in generation time is largely due to extreme variations in ecological factors, temperature (10-45°C), photoperiod (10-14 hr), relative humidity (15-95%) and rainfall. These factors also affect the percentage of pupation, emergence and fecundity of the female moths. Males outnumbered the females in the first, second and fifth generation. The females lived longer than males in all generations.Resume-Heliothis armigera (Hubner) comporte 5 generations par an aussi bien en laboratoire que dans les conditions naturelles. La premiere generation est achevee entre la premiere semaine de decembre et la quatrieme semaine de fevrier, la deuxieme entre la seconde semaine de fevrier et la premiere semaine d'avril. La troisieme generation a partir de la troisieme semaine d'aout et a travers les conditions rudes de Pete; la quatrieme generation pendant la periode de la mousson et la cinquieme et derniere generation, entre la troisieme semaine de septembre et la quatrieme semaine de novembre. La fluctuation saisonniere quant a la duree d'une generation est essentieliement liee a la variation extreme dans les facteurs ecologiques: temperature (10-45°C), la photope'riode (10-14 h), I'humidite relative (15-95%) et la pluviometrie. Ces facteurs affectent egalement le pourcentage de pupaison et d'emergence, et la fecondite des femelles. Les males surpassent en nombre les femelles dans la premiere, deuxieme, et cinquieme generation. Les femelles vivent plus longtemps que les males quelque soit la generation considered.

Diapause, migration and pyrethroid‐resistance dynamics in the cotton bollworm, HeIicoverpa armigera (Lepidoptera: Noctuidae)

“…Laboratory experiments on Sudanese H.armigera have also shown that when, some 80 days after pupation, diapausing insects are subjected to a temperature rise from 22°C to 34"C, 8% of the pupae remain in diapause for a further 2 months and only resume development when the temperature is lowered again (Hackett & Gatehouse, 1982). Similar results have been obtained for north Indian H.armigera (Tripathi & Singh, 1993). In both cases it was proposed that this enabled insects both to survive the hot dry season and to synchronize emergence with the beginning of the rains.…”

Effect of Different Sowing Dates on Pest Incidence in Chickpea

“…Its population peaks generally correspond to the full bloom and pod formation stage of the crop in the post rainy season. Temperature, relative humidity Lal 1988, Yadava et al, 1991), rainfall (Tripathi and Sharma 1985), predators (Thakur et al, 1995, Gunathilagaraj 1996 and parasitoids (Bhatnagar 1980, Srinivas and Jayaraj 1989, Thakur et al, 1995 affect the incidence and population densities of H. armigera on chickpea. Information on pest incidence under field conditions across sowing dates can be used to assess the effect of different climatic variables on pest incidence and grain yield.…”

Biology, Relative Parasitization of Larval Endoparasitoid <I>Campoletis cholrideae</I> Uchida on <I>Heliocoverpa armigera</I> Hübner under Sole and Chickpea-coriander Intercropping System

“…The H. armigera larvae found active throughout the chickpea crop (Singh and Ali, 2006). The ecological parameters viz., temperature o C), photoperiod (10-14 hrs), relative humidity (15-95%) coupled with optimal and intermittent rainfall were found to influence the population buildup, adult emergence and maximum fecundity of the female moths of H. armigera (Tripathi and Singh, 1993). The pest could be managed naturaly under field conditions by larval parasitoid Campoletis chlorideae Uchida (Hymenoptera: Ichneumonidae) in chickpea ecosystem, causes up to 78% parasitisation of early instars under natural conditions (Agnihotri et al, 2011).…”