Bollworm and tobacco budworm as cotton pests in Louisiana and Arkansas

IiitroductiouBollworms are important pests of cotton in Louisiana and Arkansas, outranked only by the boll weevil.Prior to 1949 the bollworm, Heliothis armigera (Hbn.), was regarded as the only species of importance on cot- ton.Since that time the tobacco budworm, H. virescens (F.), has been found attacking cotton in large numbers, especially in the early part of the fruiting period.Much "is known of host relationships, causes of outbreaks on cotton and other crops, natural control and insecticidal control of the bollworm.Comparatively little of such information is available on the tobacco bud- worm.Research in both states was carried on to assess the relative import- ance of the two species and to obtain information on host relationships, causes of outbreaks and methods of controlling the tobacco budworm.Efforts were also directed toward finding an explanation for the sudden rise of the tobacco budworm to the status of a serious cotton pest.Lack- ing such information, it cannot be assumed that outbreaks of this species arise from the same causes and are controlled in the same manner as the bollworm.A third species, H. sitbflexa (Gn.), was also studied because of its close resemblance to the tobacco budworm. Common NamesHeliothis armigera bears the common name of bollworm, corn ear- worm and tomato fruitworm approved by theAmericanAssociation of 1 Assistance in tlie form of a grant-in-aid from Julius H)man Division, Shell Chemi- cal Corp., to the Louisiana Agricultural Exi^eriment Station is gratefully acknowledged.