Dedication: Reginald H. Painter

Albert N. Kishaba1

1640 Sawpeck Way, Paradise, CA 95969

Additional index words. host-plant resistance, entomology, insect

Abstract. Reginald H. Painter was a pioneer researcher in the field of host-plant resistance to insects. Beginning in 1926, he and his collaborators identified sources of resistance; bred insect resistance into improved cultivars of wheat, sorgum, corn, and alfalfa; and used these successfully in wide area application. He was an early advocate of host-plant resistance, and throughout his career he promoted it as an integral component of applied entomology. Starting in 1936, he taught an advanced entomology course on the topic of insect control by means of host-plant resistance. He is credited for the formalization (Metcalf and Metcalf, 1993) of host-plant resistance as a major method of control through his text Insect Resistance in Crop Plants (1951). Many of his concepts and terms brought forth in this text, with some enlargements and clarifications, have found application in the current integrated pest management system.

1Formerly, Research Entomologist, USDA-ARS, Boyden Entomology Laboratory, University of California, Riverside, CA 92521.

Reginald H. Painter, entomologist, championed host-plant resistance to insects (HPR) through teaching, pioneering research, and through his many publications, particularly his text Insect Resistance in Crop Plants. On the front page of Breeding Plants Resistant to Insects, Maxwell and Jennings (1980) state "To Dr. Reginald H. Painter, an outstanding teacher and pioneer research worker. Many of the contributors to this volume were his students. Through his influence on them and others and in his own efforts in breeding plants resistant to insect pests, Painter helped advance the concept of integrated pest management critical to man's ability to cope with insects today."

Before proceeding further, a brief historical perspective on the study of HPR in the discipline of entomology. Haven's report in 1792 that the wheat variety Underhill was resistant to the Hessian fly is considered to be the earliest documentation of HPR. Resistance of American grape species to the grape phylloxera where the European grape species was susceptible is another classic example of HPR. Application of this knowledge led to the rescue of the French wine industry (Metcalf and Metcalf, 1993). Lindley (1831) (cited in Ortman and Peters, 1980) reported that the apple variety Winter Majetin was resistant to the wooly apple aphid. Metcalf and Metcalf (1993)

citing these historical papers said "Despite these impressive beginnings, formalization of host plant resistance as a major method of insect control began almost a century later through the investigations of R.H. Painter that were summarized in 1951." Throughout his career, Painter emphasized the importance of host plant resistance as an important dimension of applied entomology.

Ortman and Peters (1980), two of Painter's students, stated that the development of the science of plant resistance to insects could be broken into three phases. First, the pre-World War II phase during which initial observations by entomologists and cooperation with plant breeders led to the conscientious development of insect-resistant and improved cultivars. Second, the immediate post-World War II phase when pesticides were considered a great success, and the study of insect biology and HPR suffered. In the third phase, which commenced in the late 1960s and continues to the present, there has been a shift toward the development and implementation of integrated system of pest control (IPM). The development of IPM was encouraged by, among other reasons, the development of insects that were resistant to chemicals, and worldwide concern for environmental pollution. During this current phase, alternate methods of insect control including HPR have regained prominence. Painter actively worked on and promoted HPR during all three periods (Painter, 1958, 1968).


Cucurbitaceae '98

The genius of Painter is that he beat the drum for HPR not just as an end in itself, but as a part of the total discipline of applied entomology. Painter (1951) stated "...resistance of plants to insect attack may be defined as the relative amount of heritable qualities possessed by the plant which influence the ultimate degree of damage done by the insect." He also stated (Painter, 1951) that "Plant breeding itself can be viewed as man's manipulation of the evolutionary process and that insects and plants have coevolved."

According to Painter, the first review of HPR was by Snelling (1941) who listed 567 references; 37 of them were published before 1920. Painter's paper on resistance to a strain of Hessian fly in 1930 is pretty close to the beginning of HPR, and should qualify him as a pioneer in the field of HPR. As a pioneer he also recognized the problems associated with HPR. This 1930 paper according to MacKenzie (1980) was the first documentation about the problem of variability or (physiological races) in insect populations as a factor in the breakdown of HPR. Tingey and Singh (1980) wrote that Dahms and Painter (1940) were among the first to suggest that temperature can affect resistance to aphids in alfalfa.

Painter was the first to conduct a comprehensive review of HPR research progress and the general principles underlying HPR. A literature search of the subject was a monumental task in 1949; the general subject of HPR was not indexed in Biological Abstracts or in the Review of Applied Entomology. Plant Breeding Abstracts were not published at that time. Painter commented (1951) "It has been necessary to go through these abstract journals page by page, and when a reference to insect resistance was found, to check any references given in it." For those of us with computerized literature search capability, "monumental task" may be an understatement.

In the preface of his book, Painter stated "The spectacular successes of the newer types of insecticides that have been developed during and after World War II have tended to obscure the fact that there are many other ways by which insects may be controlled. Information on these other ways is not broadcast by highly paid advertising staffs. Yet there are large areas where certain crops could

not be grown profitably because of insects without the use of biological or cultural control measures. It is hoped that this volume will aid in keeping the proper balance between various methods so that insect control may have the greatest effectiveness for the least cost to both grower and ultimate consumer." We find ourselves expressing these thoughts today. They are the driving forces behind HPR and integrated pest management.

Painter, as a pioneer in HPR, led an HPR project at the Kansas Agricultural Experiment Station that was initiated in 1926. Unique at the time, the project included crops such as wheat, corn, sorghum, and alfalfa. Improved, insect-resistant varieties developed and released to Kansas' farmers include Atlas sorghum, Kawvale and Pawnee wheat, Ladak alfalfa, and a corn hybrid resistant to grasshoppers.

Starting in 1937, Painter taught an advanced entomology course on the topic of insect control by means of HPR. He introduced the concept that resistant plants can be used 1) as a principal control measure, 2) as an adjunct to other control measures, and 3) to reduce the chance release of susceptible varieties of plants. He discussed the relationship of resistant plants to the general population level of the target insect(s), to biological control, and to chemical control. He even discussed the relationship with plant breeders!

Adkisson and Dyck (1980) enlarged and clarified these terms in the present day IPM system. They reemphasized Painter's (1951) point that resistant varieties are not a magic solution to all pest problems. They proposed the use of HPR as a principal means of insect control, and the use of HPR in IPM with insecticides, biological agents, and cultural practices. Adkisson and Dyck presented outcomes of a hypothetical insect population model with and without the use of resistant cultivars over a number of generations. In one scenario, an initial population of 100 insects on a resistant cultivar increased to 4000 whereas on a susceptible cultivar the initial population of 100 increased to over one million; a 250-fold difference! Greater utility can be realized if the economic threshold is known. Thus, Painter did advance the basic concept of IPM along with HPR.

Cucurbitaceae '98

Aside from these general and specific contributions to HPR, Painter is associated with cucurbits in two publications of which I am aware. Wiseman et al. (1961) showed that where several species of insects are involved, results from field evaluations, greenhouse antixenosis and antibiosis tests with the species of insect isolated are variable. Hall and Painter (1968) reported the results of 6 years of screening for sources of squash bug and cucumber beetle resistance in 387 lines of Cucurbita sp. They reported that two lines of C. pepo, one of C. moschata, and one of C. maxima were potential sources of resistance to the squash bug and cucumber beetles.

The significance and impact of HPR in IPM was highlighted by Metcalf and Metcalf (1993) in the table (data from Klassen, 1991) "Host-resistant varieties in the suppression of major insect pests of field crops in the United States." The following numbers are in millions of hectares: corn, corn earworm, 15; corn, European corn borer, 27; sorghum, chinch bug, 7.2; barley, greenbug, 0.78; wheat, Hessian fly, 8.4; wheat, wheatstem sawfly, 0.84; alfalfa, spotted alfalfa aphid, 9.36; and cotton, lygus bug, 0.7. Painter was associated with insect resistance in five of the six field crops listed here!

Literature cited

Adkisson, P.L. and V.A. Dyck. 1980. Resistant varieties in pest management system, p. 233­251. In: F.G. Maxwell and P.R. Jennings (eds.). Breeding plants resistant to insects. Wiley, New York.

Dahms, R.G. and R.H. Painter. 1940. Rate of reproduction of the pea aphid on different alfalfa plants. J. Econ. Entomol. 33:482­485. (Cited by Tingey and Singh, 1980.)

Hall, C.V. and R.H. Painter. 1968. Insect resistance in cucurbita. Technical Kan. State Univ. Agr. Expt. Sta., Manhattan, Bul. 156.

Klassen, W. 1991. Insects in agriculture. Entomol. Soc. Amer. Centennial Symp. (cited by Metcalf and Metcalf, 1993).

MacKenzie, D.R. 1980. The problem of variable pests, p. 183­213. In: F.G. Maxwell and P.R. Jennings (eds.). Breeding plants resistant to insects. Wiley, New York.

Maxwell, F.G. and P.R. Jennings (eds.). 1980. Breeding plants resistant to insects. Wiley, New York.

Metcalf, R.L. and R.A. Metcalf. 1993. Destructive and useful insects: Their habits and control. 5th ed. McGraw Hill, New York.

Ortman, E.E. and D.C. Peters. 1980. Introduction, p. 3­13. In: F.G. Maxwell and P.R. Jennings (eds.). Breeding plants resistant to insects. Wiley, New York.

Painter, R.H. 1930. The biological strains of Hessian fly. J. Econ. Entomol. 23:322­329. (Cited by MacKenzie, 1980.)

Painter, R.H. 1951. Insect Resistance in Crop Plants. Macmillan, New York.

Painter, R.H. 1958. Resistance to of plants to insects. Annu. Rev. Entomol. 3:267­290.

Painter, R.H. 1968. Crops that resist insects provide a way to increase world food supply. Kan. State Agr. Expt. Sta. Bul. 520.

Tingey, W.M. and S.R. Singh. 1980. Environmental factors influencing the magnitude and expression of resistance, p. 87­113. In: F.G. Maxwell and P.R. Jennings (eds.). Breeding plants resistant to insects. Wiley, New York.

Wiseman, B.R., C.V. Hall, and R.H. Painter. 1961. Interactions among cucurbit varieties and feeding responses of the striped and spotted cucumber beetles. Proc. Amer. Soc. Hort. Sci. 78:379­384.

Cucurbitaceae '98