University of California

Inheritance of resistance to hydrocyanic acid fumigation in the California red scale


R. C. Dickson

Author Affiliations

R. C. Dickson was Laboratory Assistant in Entomology in the Experiment Station.

Publication Information

Hilgardia 13(9):513-522. DOI:10.3733/hilg.v13n09p513. January 1941.

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About 1914, the California red scale, Aonidiella aurantii (Mask.), was first observed to have become difficult to kill by hydrocyanic acid fumigation in a small district at Corona, California (Quayle, 1938), p. 187).4 Since that time, resistance of red scale to fumigation has increased throughout many of the citrus areas of southern California.

In 1936, the two recognized strains of red scale, “resistant” and “nonresistant,” were obtained from Corona and Glendora, California, respectively, and were grown in separate insectproof rooms in the insectary at the Citrus Experiment Station. Banana squash and, later, grapefruits were infested from these stocks at intervals of approximately six months and fumigated to determine whether these strains would maintain their difference in susceptibility to HCN. Preliminary results (Quayle, 1938) showed that the differences were maintained through several generations; later results have confirmed this (Lindgren, 1941) and show that resistance to fumigation is inherited.

The experiment described in this paper was conducted to determine how resistance to HCN fumigation is inherited in the red scale.

Review of Literature

(Hough (1928)), working with two strains of codling moth which differed in their ability to enter arsenic-sprayed apples, crossed the two strains and found the F1 hybrids intermediate between the parental strains in this regard. Later he reported (Hough, 1929) that the F1 hybrids from the reciprocal crosses were similar and that the F2 resembled the F1. By 1934 he had carried the progeny of both crosses to the F10 and still found them similar and intermediate between the parental strains (Hough, 1934). F5 moths from these crosses were backcrossed with each parental strain, and in each case the resulting progeny were found to approach, but not to be identical with, the introduced parental strain in ability to enter arsenic-sprayed fruit.

Literature Cited

Gough H. C. Factors affecting the resistance of the flour beetle, Tribolium confusum Duv., to hydrogen cyanide. Ann. Appl. Biol. 1939. 26:533-71. DOI: 10.1111/j.1744-7348.1939.tb06988.x [CrossRef]

Henking H. Untersuchungen über die ersten Entwicklungsvorgänge in den Eiern der Insekten. II. Über Spermatogenese und deren Beziehung zur Eientwicklung bei Pyrrhocoris apterus L. Ztschr. f. Wiss. Zool. 1891. 51:685-736. (Original not seen by this author; cited by Schrader, 1928.)

Hough Walter S. Relative resistance to arsenical poisoning of two codling moth strains. Jour. Econ. Ent. 1928. 21:325-29.

Hough Walter S. Studies of the relative resistance to arsenical poisoning of different strains of codling-moth larvae. Jour. Agr. Res. 1929. 38:245-56.

Hough Walter S. Colorado and Virginia strains of codling moth in relation to their ability to enter sprayed and unsprayed apples. Jour. Agr. Res. 1934. 48:533-53.

Lindgren D. L. Factors influencing the results of fumigation of the California red scale. Hilgardia. 1941. 13(9):491-511. DOI: 10.3733/hilg.v13n09p513 [CrossRef]

Quayle H. J. The development of resistance to hydrocyanic acid in certain scale insects. Hilgardia. 1938. 11(5):183-210. DOI: 10.3733/hilg.v13n09p513 [CrossRef]

Schrader Franz. The sex chromosomes. 1928. Berlin: Gebrüder Borntraeger. 194p.

Snedecor G. W. Statistical methods. 1937. Ames, Iowa: Collegiate Press, Inc. 341p. DOI: 10.1097/00010694-195702000-00023 [CrossRef]

Dickson R. 1941. Inheritance of resistance to hydrocyanic acid fumigation in the California red scale. Hilgardia 13(9):513-522. DOI:10.3733/hilg.v13n09p513

Also in this issue:

Plant nematology in California: State's: Crop losses led to first department for research in plant nematology to be established by experiment stations

Nematodes in plant quarantine: Detection of plant parasitic nematode infestations difficult because of complexity of possible causes of visible symptoms

Nematode structure and life: Wide range of life habits requires combination of characters for identification of parasites classified among nematodes

Field and vegetable crops: Wide ranges of crops and climatic conditions in California necessitate development of several diverse control programs

Nematodes in grape production: Distribution records show multiple infestations of two or more species of nematodes to be in most of California's vineyards

Citrus and avocado nematodes: Spread by nursery stock, by contaminated implements, and by water from irrigation canals that may drain infested land

Deciduous fruit and nut trees: Root-knot nematode on peach and root-lesion nematode on walnut cause serious problems for California orchardists

Nematodes on ornamentals: Root-knot, root-lesion, and more specialized or exotic forms may cause acute injuries in nursery, greenhouse, and garden

Biochemical relationships: Nematodes, plants, and linking soil components of complex problem of widespread, important pest of state's agriculture

Natural enemies of nematodes: Studies of complex soil environment aimed at favoring fungi and other organisms that limit plant nematode populations

Chemical control of nematodes: Effective nematocides relatively few in number but available in several forms for field use on perennial and annual crops

Factors influencing the results of fumigation of the California red scale

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