I liâtes Department of Agriculture uppression an Agricultural Research Service Management of Technical Bulletin No. 1684 Cabbage Looper Populations 10301 5fl,in,„3 a„. ^ ^tsville. MD 20705-2351 United States Department of Agriculture Suppression and Agricultural Research Management of Service Technical Bulletin Cabbage Looper No. 1684 Populations Abstract Preface Lingren, P.D., and G. L. Green, editors. 1984. Suppression During the 1960's and early 1970's, government research and management of cabbage looper populations. U.S. agencies (Federal and State) applied a major research Department of Agriculture, Technical Bulletin No. 1684, effort toward the development of better control proce- 152p. dures for the cabbage looper, Trichoplusia ni (Hübner). This effort resulted in several major research develop- This publication deals with a variety of factors important ments relevant to a basic understanding of insect behav- to the management and suppression of populations of ior, population dynamics, and suppression procedures. cabbage looper, Trichoplusia ni (Hübner). Its primary One of the achievements strongly influenced the devel- purpose is to provide the reader with an overview of what opment of a new suppression procedure (confusion by is known concerning natural populations of the cabbage sex pheromones) that is receding considerable attention loopers and procedures or techniques that might be used in today's insect control picture. Other results of this to suppress populations. Special emphasis is given to the research effort are commonly being used in current and distribution and dispersal of natural populations in North emerging control strategies. America. The publication contains an updated biblio- graphy of the pest and provides an analysis of research This bulletin reviews much of the research that has been needs and problems associated with the development of conducted on the cabbage looper with a special emphasis more effective control procedures. on results obtained during the 1960's and 70's that are relevant to population management and suppression. It Key words: cabbage looper, population management and also includes a great deal of previously unpublished suppression, host plants, biology, ecology, behavior, dis- information and philosophies of several authors relevant persal, distribution, sampling, population dynamics, par- to an area wide suppression effort against the cabbage asites and predators, microbial agents, chemical insecti- looper along the eastern seaboard. We hope that informa- cides, host plant resistance, cultural control, attractants, tion presented will prove useful to scientists, producers, sterilization, handling and shipment of live specimens, research managers, and students interested in entomol- research needs, bibliography. ogy and related sciences. This bulletin was originally intended for publication in 1976. This was not accomplished for reasons beyond our This publication contains the results of research only. control. Therefore, each chapter (where relevant new Mention of pesticides does not constitute a recommenda- information has evolved since 1975) has been either re- tion for use, nor does it imply that the pesticides are reg- written oran addendum attached covering information up istered under the Federal Insecticide, Fungicide, and to mid-1981. A bibliography is included, covering the Rodenticide Act as amended. The use of trade names in period of 1969 to early 1975, which updates one pub- this publication does not constitute a guarantee, war- lished by Sutherland and Sutherland (1972). Many perti- ranty, or endorsement of the products by the U.S. nent publications since 1975 are included in the literature Department of Agriculture. citations associated with each chapter presented. The year in italic, when it follows the author's name, ref- P.D. Lingren, U.S. Department of Agriculture (USDA), ers to Literature Cited at the end of each chapter. Data Agriculture Research Service (ARS), Western Cotton presented in the references, figures, and tables are repro- Research Laboratory, Phoenix, Ariz., and G. L. Green, duced essentially as they were supplied by the author(s) Kansas Agricultural Experimental Station, Garden City, of each chapter. are primarily responsible for selection of senior authors and in coordinating the collation of this bulletin. Many scientists were involved in the research presented and reviewed herein, and their contributions are very signifi- cant and deeply appreciated; however, we must not over- look the leaders involved in any effort. Therefore, we ded- icate this technical bulletin to three of the primary leaders of the research that was conducted on the cabbage looper during the 1960's and 70's: E. F. Knipling and T. J. Henneberry of USDA, ARS, and H. H. Shorey, Uni- versity of California, Riverside. Ill Contents Part 1. Natural Populations Page Part III. Handling and Shipping Techniques Chapter 1 .—Cultivated and Wild Host Plants by D. W. S. Chapter 16.—Handling and Shipping Laboratory Sutherland and G. L. Greene 1 Reared Live Specimens by H. H. Toba and P. D. Lingren 121 Chapter 2.—Biology, Behavior, and Dispersal of Adults by E. R. Mitchell and R. B. Chalfant 14 Part IV. Research Needs Chapter 17.—Research Needs and Problems Asso- Chapters.—Release, Recovery, and Dispersal of ciated with Developing Effective Control Programs Adults by J. W. Debolt, T. J. Henneberry, W. W. by T. J. Henneberry and W. Klassen 127 Wolf, and P. D. Lingren 19 Part V. Updated Bibliography (1969-75) Chapter 4.—Potential for Dispersal by Winter Ship- Chapter 18.—A Contribution to a Bibliography of the ments of Vegetables, Ornamental Plants, and Cut Cabbage Looper, Trichoplusia ni (Hübner) by Flowers by S. L. Poe and R. B. Workman 26 D. W. S. Sutherland and A. V. Sutherland 133 Chapters.—Seasonal Populations of Eggs and Larvae Chemicals Mentioned in This Publication 149 in North America by G. L. Greene 30 Chapter 6.— Larval Population Sampling and Economic Thresholds by M. Shepard and G. L. Greene 36 Microfiche copies can be purchased from the National Chapter 7.—Computer Simulations of Development by Technical Information Office, 5285 Port Royal Road, G. D. Butler, Jr 41 Springfield, Va. 22161. Chapters.-Diseases by C. Ignoffoand D. L. Agricultural Research Service has no additional copies Hostetter 45 for free distribution. Part II. Control Technologies Chapters.-Chemical insecticides and Resistance by C. S. Creighton 57 Chapter 10.—Utilization of Entomopathogens as Con- trol Agents Against Larvae in Various Agroecosys- temsby D. L. Hostetter and C. Ignoffo 67 Chapter 11 .—Role of Parasitoids and Predators in Regulating Populations by P. B. Martin, P. D. Lingren, and G. L. Greene 76 Chapter 12.—Host Plant Resistance by F. P. Cuthbert, Jr. and A. N. Kishaba 92 Chapter 13.—Population Reduction with Cultural Man- agement by R. B. Workman 97 Chapter 14.—Premating Communication and Exploita- tion of the Sex Pheromone by J. R. McLaughlin 99 Chapter 15.—The Current Status of Induced Sterility for Population Suppression by P. D. Lingren, D. T. North, H. H. Toba, and T. J. Henneberry 112 Issued September 1984 IV Part 1. Natural Populations Chapter 1. Cultivated and Wild Host Plants (1971) found T. ni preferred collards and cotton to broc- By Douglas W. S. Sutherland^ and G. L. Greene2 coli, cabbage, and cauliflower for oviposition. Greene (1970) tested 14 crucifer varieties under medium to high Abstract looper population densities and found egg and larval The cabbage looper, Trichoplusia ni (Hübner), is listed as numbers were similar on the reported resistant and pre- feeding on over 160 species of plants in 36 families. Culti- ferred varieties at high population densities in the field. vated crucifers are preferred. In addition, some 50 host species were checked for looper development in Florida. Elsey and Rabb (7967) determined that the density and Twenty of these produced adults whereas 23 were not gumminess of trichomes on tobacco leaves reduced the suitable hosts. survival of early instar cabbage loopers. Radcliffe and Chapman (1966b) suspected that the hairiness of the leaves of Chinese cabbage and turnip may be a factor in their resistance to oviposition, and that the comparative The cabbage looper, Trichoplusia ni (Hübner), has a resistance of kohlrabi may be due to its small total leaf diverse host range as is indicated by the species and fam- surface. ily range of hosts. It has been reported on at least 160 species, varieties, or cultivars of plants in 36 families even Radcliffe and Chapman (1965a, 1965b, and 7966b) found though cultivated crucifers appear to be favored when no correlation between plant size and susceptibility of the available (Riley, 1881, 1883; Wene and Otey 1955; Brett et various cabbage varieties to looper oviposition. Signifi- al. 1958; Genung 1960; David 1960). In greenhouses, cant differences in ovipositional preference on broccoli many ornamentals and a few vegetables, such as lettuce, and cauliflower plants of different ages were noted by are attacked during late fall and winter (Sirrine 1897; Brit- Boling and Pitre (1971). The stratification of T. ni oviposi- ton 1910; Smith et al. 1952). Weeds have only been shown tion sites and larval distribution on cabbage were studied to be important hosts of the cabbage looper in the south- by Sutherland (7966) and Greene (7968). western United States (McKinney 1944) and in Israel (Avidovand Harpaz 1969). Sutherland (7966) found differences in larval development of T. ni on peppers as compared with that on cabbage, A number of authors have evaluated cabbage varieties lambsquarters, lima bean, and tomato grown in field and other crucifers for resistance to the cabbage looper. cages. A separate preliminary study indicated that hosts Harrison and Brubaker {1943) concluded that no crucifer also affected adult longevity and egg production (Suther- cultivar was resistant to attack and that differences were land 7966). Shorey etal. (7962) showed that T. n/devel- due to the amount of foliage, stage of maturity, height, oped more rapidly on lima bean foliage than on cabbage and general physical condition of the plant. Harcourt at 73.4° F.