COMPARATIVE EFFECTIVENESS AGAINST THE GRANARY WEEVIL OF CONTACT, FUMIGATION AND REPELLENCY OF PYRENONE, PYRETHRINS, PIPERONYL BUTOXIDE, LINDANE AND DDT DISSERTATION Presented In Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy In the Graduate School of the Ohio State University By YUNG CHANG CHAO, B.A., M.S. The Ohio State University 1952 Approved bys CONTENTS Pago ACKNOWLEDGMENTS ..................... .............. Ill INTRODUCTION ................................... 1 LITERATURE R E V I E W ................................. 4 CULTURE METHODS ...... ........................... 11 EXPERIMENTATION ................................. 15 Experimental Design ................... 15 Equipment ................ 16 Toxicants and. Adjuvants ...................... 19 Formulations ................................. 26 Application Technique ........................ 31 Collecting D a t a ...... 40 RESULTS AND DISCUSSION ............................ 44 STATISTIC ANALYSIS ................................ 54 CONCLUSION ............ 57 SUMMARY ........................................ 59 ILLUSTRATIONS .. ................... 61 LIST OF ABBREBIAT IONS ............................. 81 LITERATURE CITED ............................... 82 AUTOBIOGRAPHY..................................... 86 I S00441 LIST OP TABLES Table Page 1 Formulation of Impregnated Dusts for 50-gram Stocks........................................ 29 2 Emulsion Concentrates for Experiments 4 and 5.. 31 3 Formulation of Emulsion Concentrate for the Study of Contact Toxicity............ 31 4 The Differences In Adult, Pupal and Larval Stages of Rice Weevil and Granary Weevil....... 32 5 Dosages of Active Ingredients in PPM of Wheat.. 35 6 Dosages of the Five Toxicants Applied to Wheat in PPM.......................... 37 7 Average Weight of Feces from Treated Wheat and Difference in Weight of Feces between Treated Wheat and Checks...................... 47 8 Contact Effect of Toxicants Impregnated on Bags after 2§ Months...................... 50 9 Comparative Effect of Lindane Impregnated Bags in Closed Jars and in Open Jars Showing by the Number of Adults Developed after 100 Weevils Being Exposed Six Days and Collected 50 Days after the Removal of 100 Beetles ........ 51 10 Showing the Results of Four-Week Fumigation by Lindane Impregnated on Bags against Immature Granary Weevils of 1-4 Weeks ............. 53 ii ACKNOWLEDGMENTS The author wishes to express his most sincere gratitude to Dr. Dwight M. DeLong under whose direction this work was carried on. Dr. A. Peterson under whose direction this work was inaugurated suggested the problem. Dr. Harold E. Gray, in charge of the Stored Product Insect Investigations, Division of Entomology, Department of Agriculture, Ottawa, Canada, suggested the study of pyrenone. Dr. W. E. Dove, Director of Entomology Division of Re­ search and Development Laboratory, U.S. Industrial Chemicals, Inc., furnished a great deal of information on the use of pyrenone. Dr. Samuel S. Ristich offered much valuable information on the formulation of insecticides and helped in taking the photographs. Dr. D. P. Miller kindly approved all the orders for equipment and materials employed In this work. Dr. Prank W. Pisk, in charge of the Matheison Chemical Corporation Project at the Ohio State University, permitted the use of the ball mill and the taking of Its picture. Matheison Chemical Corporation Project at the Ohio State University gave the facility of using a number of materials for insecticidal studies. H i Ohio Seed Improvement Laboratory at the Ohio State University helped to determine the water content of the samples of wheat with the Tag-Happenstall Moisture Meter and supplied some of the wheat used in tests* U.S. Industrial Chemicals, Inc. supplied the samples of pyrenone, pyrethrins, piperonyl butoxide and several diluent dusts• California Spray Chemical Corporation furnished the sample of lindane* Attapulgus Clay Company supplied the sample of Atta- clay SP* To these men and companies that contributed much toward the work, the author is very grateful* iv INTRODUCTION Along with, the unprecedented, development of insecticides in the past decade a new approach to the control of the stored grain insects has been laid. Among the newer in­ secticides synthetic chlorinated compounds received immedi­ ate attention. However, toward the close of the decade at­ tention was turned to the combination of pyrethrins and their synergists. Among the chlorinated compounds lindane is es­ pecially promising for the control of stored grain insects because it has several unsurpassed properties. The so- called pyrenone, the combination of pyrethrins and piperonyl butoxide Is considered the most promising insecticide for controlling stored grain Insects because it gives not only rapid "knock-down," greater mortality and longer residual action but also offers safe use for human beings. In addi­ tion to the well-known properties of lindane and pyrenone, lindane is assumed to act as a fumigant and pyrenone and/or its ingredients as a repellent. These new properties are perhaps more favorable to the control of stored grain in­ sects. Their study may afford the bases of their new uses. However, a detailed survey of literature Indicates that little work has been done in connection with the new proper- 2 ties of lindane and pyrenone. The problem of Stored Grain Insect Control which was chosen as the author's doctorate study was first specified as Stored Grain Insect Control by Use of Newer Insecticides. A little later the problem was narrowed down to Fumigation Effect of Lindane. Still later Repellence Effect of Pyre­ none and Its Ingredients, and Lindane; and Contact Effect of the Same Toxicants were added to the study. Thus, the problem was finally shaped as Comparative Effectiveness, against Stored Grain Insects,of Contact, Fumigation, and Repellence of Lindane, Pyrenone, Pyrethrins and Piperonyl Butoxide. Judging from the excellent properties and new uses of the selected insecticides the present form of the problem seems logical and advisable. During the study six experiments were carried out: experiments 1 and 6 for contact effect; experiments 2, 4 and 5, for fumigation effect; and experiment 3 for re­ pellence effect. These experiments were conducted by two methods: experiments 1, 2 and 3 were conducted by use of i impregnated dusts and experiments 4, 5 and 6, by use of im­ pregnated cloth bags. The work is the result of four quarters investigations in the laboratory at the Ohio State University. One of the Important findings of the study Is the relative toxicity and stability of pyrenone and lindane. Another finding is the 3 effectiveness of lindane vapor against the adult and im­ mature stages of the granary weevil. LITERATURE REVIEW To obtain the best, first-hand and up-to-date references to the present work a detailed survey of literature was made, 'This survey indicated that the work on the evaluation of the effect of DDT, BHC and pyrenone against stored grain Insects was so crowded that only outstanding papers could be briefly summarized in this review. The papers which are to be re­ viewed were essentially obtained from Biological Abstracts and Bibliography of Agriculture, from 1941 to 1951, and some other sources. In addition, some information was obtained by personal communications. The applications of the three insecticides to stored grain insects include three categories, namely: (1) control by spraying warehouses and boxcars, (2) control by mixing chemicals with grain and (3) control by impregnation of sacking. The category (1) will be omitted herein since it is not incorporated in the present work. The remaining categories are separately discussed as follows: I. Control by Mixing Chemicals with Grain. This cate­ gory will be dealt with under the following two topics. A. Protection of grain for seed purpose. It is most probable that far more work on this subject has been done than on any other subject dealt with later. Among many 4 5 workers along this line Cotton, Hammer, Farrar and Kulash 1 p deserve mention especially. Cotton * noted that an effec­ tive treatment consists of 3$ DDT in magnesium oxide applied at the rate of 0.05$, by weight, of the seed mixture or ig- oz of the mixture per bushel of seed. He also suggested BHC at 3 ^ 1 PPM for seed protection. Hammer found that 3% DDT dust at the rate of 1.5 ozs per bushel affords protection of seed corn against the rice weevil, Anguomois moth and Indian meal 4 moth for 223 days without affecting germination. Farrar demonstrated that satisfactory protection of fifteen kinds of seed against eight species of grain insects for a whole year results from the application of 2 .5 -20% DDT dust at the rate of 1.5 ozs per bushel. It is apparent that the results obtained by the three workers are very similar. Kulash ob­ tained the satisfactory results by spray or slurry method. He treated husked, unhusked and shelled corn by spraying DDT solution. He also treated shelled corn by applying DDT emul­ sion or slurry. B. Protection of grain for human consumption. 6 1. DDT. ZInkernagel found that wheat may be pro­ tected by 10$ DDT dust at the rate of 0.1$. It is shown that the residual left is only 9 PPM after the grain is cleaned and 4-6 PPM after milling which is below the United States official tolerance of 7 PPM. Ho ill effects were observed in laboratory animals that fed for seventy days on the treated 6 grain that had not undergone any of the normal cleaning 7 processes or on bread baked from it. Gay showed that DDT at the concentration of 4 PPM produces a 50$ kill of the rice weevil in ten days. For some years DDT has been practically applied to 8 stored grains for food to some extent in Switzerland, Bel- Q glum and some other parts of the world. However, from a recent personal communication it became known that the use of DDT in protecting grain for food purpose was much re- 8 duced. This is most probably due to the fact that the ac­ cumulation of DDT was shown in body tissues of mammals. 2, BHC. Slade'1'0 first observed that BHC is ex­ ceptionally toxic to the rice weevil when applied to grain at the concentration of 1 PPM.