University of California

The toxic effect of certain chemical solutions on spores of Penicillium italicum and P. digitatum


Liang Hwang
L. J. Klotz

Authors Affiliations

Liang Hwang was Research Fellow of China Foundation for the Promotion of Education and Culture; L. J. Klotz was Associate Plant Pathologist in the Experiment Station.

Publication Information

Hilgardia 12(1):1-38. DOI:10.3733/hilg.v12n01p001. October 1938.

PDF of full article, Cite this article


Abstract does not appear. First page follows.


The blue and the green molds (Penicillium italicum Wehmer and P. digitatum Sacc.) are the most common fungi causing soft decay in citrus fruits. They are world-wide in distribution, affecting fruits in orchards, in packing-houses, during transportation, and on the markets. In 1908, Powell (27) reported that the losses from blue-mold decay in oranges during transportation from California were from $750,000 to $1,500,000 annually.

According to Sawada’s (34) report in 1922, the two molds caused decay of oranges in Italy, the United States, Japan, and Formosa. Tindale (38) stated that in Victoria blue and green molds are the greatest enemies of oranges in cold storage and elsewhere. He (39) also reported that after two months’ cold storage blue mold developed extensively. In 1928, Barker (7) stated that green mold causes serious losses in oranges from Spain, Palestine, Brazil, and the Argentine; less extensive damage is caused to oranges from South Africa, Australia, and California, and to grapefruit from Florida, Puerto Rico, and South Africa. In the same year Reichert and Littauer (32) reported that blue and green molds developed on picked fruit in Palestine.

Literature Cited

[1.] Australian Citrus Preservation Committee. Export of citrus fruit. Jour. Australia Council Sci. and Indus. Research. 1931. 4:96-99.

[2.] B &; C Scientific Products, Inc. The Staklor method of blue mold control. 1935. Seattle, Wash: B &; C Scientific Products, Inc. 12p. (Special folder.)

[3.] Baker K. F., Heald F. D. Investigations on methods of control of the blue-mold decay of apples. Washington Agr. Exp. Sta. Bul. 1934. 304:1-32.

[4.] Barger W. R. Treating oranges with borax solution for control of blue and green mold. California Citrograph. 1925. 10:149

[5.] Barger W. R. Sodium bicarbonate as a citrus fruit disinfectant. California Citrograph. 1928. 13:164 172-74.

[6.] Barger W. R., Hawkins L. A. Borax as a disinfectant for citrus fruit. Jour. Agr. Research. 1925. 30:189-92.

[7.] Barker J. Wastage in fruit commerce. [Gt. Brit.] Dept. Sci. and Indus. Research. Food Invest. Bd. Rept. 1928. 1927:38-42.

[8.] Bates G. R. II. Wastage during the 1932 export season. British South Africa Co. Mazoe Citrus Exp. Sta. Pub. 1933. 2c:155-76.

[9.] Benton R. J. Prevention of decay in oranges. Agr. Gaz. N. S. Wales. 1931. 42:411-13.

[10.] Brogdex Company. The successful control of blue mold decay in marketing citrus fruits. The borax treatment and the patent situation. 1925. Brogdex Co.: Los Angeles and Winterhaven. 49p.

[11.] Charter Oak House. Charter Oak House tests sodium hypochlorite process. California Citrograph. 1925. 10:417 446-47.

[12.] Doidge E. M. Some diseases of citrus prevalent in South Africa. So. African Jour. Sci. 1929. 26:320-25.

[13.] Fawcett H. S. The decay of citrus fruits on arrival and in storage at eastern markets. California Citrograph. 1925. 10:79 98, 103.

[14.] Fawcett H. S. Citrus diseases and their control 1936. 2nd ed.p.656. p. (See specifically P. 387-99.) McGraw-Hill Book Co. Inc., New York, N. Y.

[15.] Fawcett H. S., Barger W. R. Relation of temperature to growth of Penicillium italicum and P. digitatum and to citrus-fruit decay produced by these fungi. Jour. Agr. Research. 1927. 35:925-31.

[16.] Fawcett H. S., Klotz L. J. Protecting the fruit and foliage of citrus from brown rot. Univ. California Citrus Exp. Sta. 1936. p.2. p. (Mimeo.)

[17.] Fulton H. R., Bowman J. J. Preliminary results with the borax treatment of citrus fruits for the prevention of blue mold rot. Jour. Agr. Research. 1924. 28:961-68.

[18.] Fulton H. R., Winston J. R. Controlling blue mold rot of citrus fruits with borax solution. Florida Grower. 1924. 30(18):7

[19.] Hodgson R. W. Borax treatment. A letter addressed to the Director of Agriculture and Forests, Jerusalem. Palestine Citrograph. 1928. 1:3

[20.] Hopkins J. C. Report of plant pathologists for year ending December 31, 1929. South. Rhodesia Dept. Agr. Rept. of Secretary. 1930. 1929:84-86.

[21.] Klotz L. J. Nitrogen trichloride and other gases as fungicides. Hilgardia. 1936. 10(2):27-52. DOI: 10.3733/hilg.v10n02p027 [CrossRef]

[22.] Marloth R. H. Influence of hydrogen-ion concentration and of sodium bicarbonate and related substances on P. italicum and P. digitatum. Phytopath. 1931. 21:169-98.

[23.] McCallan S. E. A., Wilcoxon F. The precision of spore germination tests. Boyce Thompson Inst. Contrib. 1932. 4:233-43.

[24.] Nattrass R. M. Prevention of wastage of citrus fruit in transit. Cyprus Agr. Jour. 1935. 30:84-87.

[25.] Osterhout W. J. V. The effect of alkali on permeability. Jour. Biol. Chem. 1914. 19:335-43.

[26.] Osterhout W. J. V. The effect of acid on permeability. Jour. Biol. Chem. 1914. 19:493-501.

[27.] Powell G. H., et al. The decay of oranges while in transit from California. U. S. Dept. Agr. Bur. Plant Indus. Bul. 1908. 123:1-79.

[28.] Powell H. C. The control of blue and green mold of oranges. So. Africa Fruit Grower. 1926. 9(13):232

[29.] Putterill V. A. The prevention of mould wastage in oranges. Union So. Africa Dept. Agr. Bul. 1930. 64:1-20.

[30.] Putterill V. A. Citrus wastage investigations progress report No. 3. 1934. Union So. Africa Dept. Agr. Bul. 1935. 149:5-27.

[31.] Putterill V. A., Davies R. Citrus wastage investigations carried out at Zebediela, Transvaal, during the seasons 1931 and 1932. Union So. Africa Dept. Agr. Bul. 1934. 128:7-49.

[32.] Reichert I., Littauer F. The decay of citrus fruits in Palestine and its prevention. Palestine Citrograph. 1928. 1(8):4-7. 1: 9 5-8.

[33.] Reichert I., Littauer F. Preliminary disinfection experiments against mould wastage in oranges. Hadar. 1931. 4(3&;4):3-18.

[34.] Sawada K. Blue mold of sweet orange (Penicillium italicum). Descriptive catalogue of Formosan fungi, part II. Formosa Dept. Agr. Gov. Research Inst. Rept. 1932. 2:128-30.

[35.] Shiver H. E. Disinfecting and washing citrus fruit. Chem. and Metall. Engin. 1925. 32:812

[36.] Stewart R. M. Interesting new uses of soluble borates in the packing houses. Florida State Hort. Soc. Proc. 1935. 48:42-44.

[37.] Takeuchi H. Penicillium rots of citrus fruits. Kjusu Imp. Univ. Bul. Sci. Fakultato Terkultura. 1929. 3:333-49.

[38.] Tindale G. B. Cool storage of Washington Navel oranges. Results of 1926 experiments. Jour. Dept. Agr. Victoria. 1927. 25:74-80.

[39.] Tindale G. B. Valencia late oranges. Cool storage experiments. Jour. Dept. Agr. Victoria. 1927. 25:276-79.

[40.] Tomkins R. G., Trout S. A. The use of ammonia and ammonium salts for the prevention of green mold in citrus. Jour. Pomol. and Hort. Sci. 1931. 9:257-64.

[41.] Winston J. R. Reducing decay in citrus fruits with borax. U. S. Dept. Agr. Tech. Bul. 1935. 488:1-32.

[42.] Young W. J., Read F. M. The preservation of citrus fruit. Progress report of the citrus preservation committee. Jour. Australia Council Sci. and Indus. Research. 1930. 3:69-76.

[43.] Yu T. F. Notes on the storage and market diseases of fruits. I. Jour. Agr. Assoc. China. 1934. 123:16-27.

Hwang L, Klotz L. 1938. The toxic effect of certain chemical solutions on spores of Penicillium italicum and P. digitatum. Hilgardia 12(1):1-38. DOI:10.3733/hilg.v12n01p001
Webmaster Email: wsuckow@ucanr.edu