24 MISC. PUBLICATION 3 4 0, TJ. S. DEPT. OP AGRICULTURE 



those seen on ripe fruit are usually the larger, partly because the fungus 

 has had a longer time in which to grow and partly because develop- 

 ment of the rot on ripe fruit is more rapid. 



CAUSAE FACTORS 



Tan brown rot is caused by the fungus Pezizetta lythri, which has 

 been known under a variety of other names. The fungus has three 

 different stages and three different spore forms. In one or another of 

 its stages it is found on about 50 different host plants widely distri- 

 buted throughout North America and Europe and is also found in South 

 America. It is a weak parasite that usually, perhaps always, is de- 

 pendent on some injury for a way of entrance into the host. De- 

 velopment of the rot is favored by warm wet weather. 



CONTROL MEASURES 



Mulching with pine needles or straw is apparently the only method 

 of controlling tan brown rot in the field. Control in transit and on the 

 market depends on careful handling, temperatures below 45° F., and 

 prompt movement of the shipments {8, 11, 36, 38). 



LITERATURE CITED 



(1) Bain, Henry, F. 



1926. CRANBERRY DISEASE INVESTIGATIONS ON THE PACIFIC COAST. U. S, 



Dept. Agr. Bull. 1434, 29 pp. 



(2) Bergman, H. F. 



1935. COOPERATIVE CRANBERRY INVESTIGATIONS. Mass. Agr. Expt. Sta. 



(Ann. Rept. 1934) Ball. 315: 32-34. 



(3) Bioletti, Frederic T. 



1907. oidium or powdery mildew of the vine. Calif. Agr. Expt. Sta. 

 Bull. 186, pD. [315]-352, illus. 



(4) 



1923. BLACK MEASLES, WATER BERRIES AND RELATED VINE TROUBLES. 



Calif. Agr. Expt. Sta. Bull. 358, pp. [509]-524, illus. 



(5) and Flossfeder, F. C. H. 



1915. oidium or powdery mildew of the vine. Calif. Agr. Expt. Sta. 

 Cir. 144, 12 pp., illus. 



(6) Bonnet, L. O. 



1926. A PROMISING REMEDY FOR BLACK MEASLES OF THE VINE. Calif. 



Agr. Expt. Sta. Cir. 303, 10 pp., illus. 



(7) 



1928. enemies of the flower and fruit. Calif. Grape Grower 9 (3): 



6, 7. 



(8) Brooks, A. N., Watson, J. R., and Mowry, Harold. 



1929. STRAWBERRIES IN FLORIDA. CULTURE, DISEASES AND INSECTS. 



Fla. Agr. Expt. Sta. Bull. 204, pp. [481J-523, illus. 



(9) Cruess, W. V. 



1918. THE FERMENTATION ORGANISMS OF CALIFORNIA GRAPES. Calif. 



Univ. Pubs., Agr. Sci. 4: 1-66, illus. 



(10) Darrow, G. M., and Detwiler, S. B. 



1924. CURRANTS AND GOOSEBERRIES I THEIR CULTURE AND RELATION TO 



white-pine blister rust. U. S. Dept. Agr. Farmers' Bull. 

 1398, 42 pp., illus. (Revised, 1934.) 



(11) Dodge, B. O., and Stevens, Neil E. 



1924. THE RHIZOCTONIA BROWN ROT AND OTHER FRUIT ROTS OF STRAW- 

 BERRIES. Jour. Agr. Research 28: 643-648, illus. 



(12) du Plessis, S. J. 



1936. STUDIES ON THE WASTAGE OF EXPORT GRAPES WITH SPECIAL REFER- 

 ENCE TO THAT CAUSED BY BOTRYTIS CINEREA, PERS. Union So. 



Africa Dept. Agr. and Forestrv Sci. Bull. 151, 163 pp., illus. 



(13) Eyer, J. R., and McCubbin, W. A. 



1926. grape insects and diseases. Pa. State Dept. Agr. Bull. v. 9, 

 no. 16 (Gen. Bull. 433), 27 pp., illus. 



