Determination of lepidopterous pests on cotton, their population development, natural enemies and the biology of spiny bollworm ((earias insulana (boisd. ) lepidoptera: noctuidae)) and their interaction between plant phenology in Şanlıurfa

ABSTRACT PhD THESIS DETERMINATION OF LEPIDOPTEROUS PESTS ON COTTON, THEIR POPULATION DEVELOPMENT, NATURAL ENEMIES AND THE BIOLOGY OF SPINY BOLLWORM [{Earias insulana (Boisd.) LEPIDOPTERA: NOCTUIDAE] AND THEIR INTERACTION BETWEEN PLANT PHENOLOGY IN ŞANLIURFA Levent UNLU DEPARTMENT OF PLANT PROTECTION INSTITUTE OF NATURAL AND APPLIED SCIENCES UNIVERSITY OF ÇUKUROVA Supervisor : Prof. Dr. Serpil KORNOŞOR Year 2001, Pages: 110 Jury : Prof. Dr. Serpil KORNOŞOR Prof. Dr. Avni U?UR Prof.Dr. A.Faruk ÖZGÜR Eight lepidopterous species were found as the pests of cotton in 1998-2000 in Şanlıurfa and its provinces. These are Agrotis spinifera (Hübn.), A. segetum (D.-S.), A. ipsilon Hufn., Spodoptera exigua (Hübn.), S. littoralis (Boisd.), Helicoverpa armigera (Hübn.), Earias insulana (Boisd.) and Pectinophora gossypiella (Sound). Among them, H. armigera, E. insulana and P. gossypiella were the most injurous species. H. armigera, a pest of boll formation and maturation stages of cotton, has not caused injury for all year; however, its population reach the maximum level in 1998. Increasing Spiny Boll Worm population, during maturation stage, caused remarkable damages in 1999. While being quite low in 1998, Pink Boll Worm population increased in 1999. The blind bolls collected after harvest revealed that Şanlıurfa and provinces were infested with Spiny Boll Worm and Pink Boll Worm. The average infestation levels of the blind bolls in Harran Plain in 1998, 1999 and 2000 were determined 13.7%, 43.1% and 26.6%, respectively; for provinces' infestations levels were 16.6%, 17.7% and 8.2%, respectively. The biology of Spiny Boll Worm was studied in laboratory on the artificial diet at four different temperatures (21, 25, 29 and 33±1°C), %70±5 relative humidity and 16:8 L:D period The time required for development from egg to adult was the longest on 21°C and the shortest on 29°C. Key Words: Earias insulana, Lepidoptera, Cotton, Harran Plain, Pest Biology II