Earias  insulana  ( Boisd )( Lepidoptera : Phalaenidae ) EFFECT OF PLANTING  DATES  AND SUSCEPTIBILITY  OF SOME COTTON VARIETIES TO SPINY BOLL WORM INFESTATION EARIAS  INSULANA (BOISD.) ( LEPIDOPTERA : PHALAENIDAE)

	Earias insulana ( Boisd )( Lepidoptera : Phalaenidae ) EFFECT OF PLANTING DATES AND SUSCEPTIBILITY OF SOME COTTON VARIETIES TO SPINY BOLL WORM INFESTATION EARIAS INSULANA (BOISD.) ( LEPIDOPTERA : PHALAENIDAE)
AL-TAQANI
Article 1, Volume 21, Issue 2, 2008, Pages 0-0
Abstract
The spiny boll worm E. insulana (Boisd.) is one of the most important cotton pests in Iraq . Harmful damage might occur to seedling , leaf buds ,flower buds and bolls leading to a significant decrease of cotton yield. Field studies were conducted to evaluate the effect of planting dates and the susceptibility of some cotton varieties during growth stages . Lashata cotton variety was planted in three periods (1st date 15/3/2004 ,2nd date 1/4/2004 and 3rd date 15/4/2004 ). Results showed that cotton plants planted at 1st date had lower infestation percentage( 0.00 , 2.70 , 19.45 and 24.64 %) during growth stages ( seedling , leaf buds , flower buds and bolls ) respectively and the general infestation percentage for the entire plant was 11.60%. compared with 2nd and 3rd dates in which percentage were 15.13 and 21.44% respectively .Four varieties of cotton ( Asahour , Lashata , Marsoumi and Cooker 100 wilt) were planted at 15/3/2004 . Results show significant differences between the varieties with regard susceptibility to infestation . (Cooker 100 wilt ) variety was the least sensitive to infestation ( 0.00% in seedling stage , 2.10% in leaf stage , 18.82% in flower stage and 24,47% in bolls stage) The general infestation percentage for the entire plant was 11.34 % .. Marsoumi variety was most susceptible host to this insect . However the average percentages were ( 0.00 , 4.30 , 22,25 and 35.35 % ) in seedling stage , leaf buds , flower stage and bolls formation respectively. And the total infestation in the plants was 15.47%.

Statistics Article View: 110 PDF Download: 2