Heat Unit Requirements for Development of the Pink Bollworm Pectinophora gossypiella (Saund.)

S., Yones M.; A., Abd ElRahman H.; F., Abou Hadid A.; M., Arafat S.; F., Dahi H.

doi:10.21608/eajbsa.2011.15176

Heat Unit Requirements for Development of the Pink Bollworm Pectinophora gossypiella (Saund.)

Document Type : Original Article

Authors

¹ National Authority for Remote sensing and Space Sciences (NARSS), 23, Josef proztito St. Elnozha Elgedida - P.O. Box 1564 Alf maskan Cairo, Egypt

² Faculty of Science, Ain Shams University, Egypt

³ Minstry of Agriculture, Egypt

⁴ Plant Protection Research Institute, Giza, Egypt

10.21608/eajbsa.2011.15176

Abstract

The present study was carried out under four
constant temperatures (20, 25, 30 and 35°C each ± 1°C) when the Pink Bollworm, Pectinophora
gossypiella (Saund.) larvae,were fed on artificial diet. The time
required for embryogensis, larval duration and pupal duration decreased as the
temperatures increased from 20 to 35°C. The lower thresholds of development (t₀)
were 9.91, 14.07, 9.57 and 12.18°C for eggs, larvae, pupae and pre-oviposition
period, respectively. The average accumulated heat units required for
development was 72.11, 166.38, 248.70 and 26.83degree-days for egg, larvae,
pupae and pre-oviposition period, respectively. The lower threshold of
development (t₀) to complete a generation was 12.03°C. The average
accumulated heat units required for a generation was 499.71 degree-days. The
kind of food had non-significant effect for heat requirements. The thermal
units required to complete the development of different stages to complete one
generation, as well as helping in the design of development indexes,
determining the times required for these stages under fluctuating temperatures
in field and forecasting system for establishment and develop the non chemical
methods for the pink bollworm IPM program.

Keywords