TRANSPORTATION ROTS OF STONE FRUITS AS 

 INFLUENCED BY ORCHARD SPRAYING 



By Charles Brooks and D. F. Fisher, Pathologists, Fruit Disease Investigations, 

 Bureau of Plant Industry, United States Department of Agriculture 



The present paper reports the pathological results of five years' ship- 

 ping and storage experiments with green prunes and sweet cherries and 

 is an attempt to demonstrate certain underlying facts that help to place 

 the responsibility for transportation and market losses in perishable 

 fruit shipments. Sprayed fruit and dusted fruit have been compared 

 with untreated fruit from the same orchards under various transportation 

 and storage conditions. 



Spoilage of fruit has been almost entirely due to Monilia or brown rot 

 [Sderotinia cinerea (Bon.) Wor.], blue mold rot [Penicillium expayisum 

 (Lk.) Thom], and black mold rot [Rhizopus nigricans Ehr.]. Monilia 

 attacks the fruit both in the orchard and on the market, but Penicillium 

 and Rhizopus are able to develop only on the harvested fruit. 



SPRAYED AND UNSPRAYED SWEET CHERRIES IN TRANSIT AND IN 



STORAGE 



The shipping experiments on cherries were made from the orchard of 

 L. T. Reynolds of Salem, Greg. The varieties used were Napoleon 

 (Royal Ann), Black Republican, and Lambert. Various standard spray 

 materials were used on the different orchard plots, including 2-4-50 

 Bordeaux plus 2 pounds of rosin fish-oil soap, 8-8-50 self-boiled lime- 

 sulphur plus 2 pounds of rosin fish-oil soap, and commercial lime sulphur 

 diluted I to 50. In the 1919 experiments a neutral Bordeaux (4 pounds 

 copper sulphate in 100 gallons water neutralized with lime) was substi- 

 tuted for the 2-4-50 Bordeaux, a casein spreader ^ was added to the lime 

 sulphur solution, and one plot was treated with 85-0-15 ^ sulphur dust. 



In 19 15 sprayings were made May 7 and 8 and June i ; in 19 16, April i, 

 April 21, May 12, and June 15; in 1917, April 25, May 14, May 31, and 

 June 22; in 1918, April 15, May 2, May 17, and June 18; and in 1919, 

 June 7 and June 16. The earlier applications (before May 10) were for 

 the control of blossom infection and probably had little effect upon the 

 occurrence of rot on the ripe fruit. 



In 1915 and 1916 there was practically no foliage injury from any of 

 the spray materials used, but in each of the following three years very 

 definite injury occurred on particular plots. In 1917 and 1918 lime 

 sulphur caused heavy defoliation, and in 19 19 Bordeaux produced con- 

 siderable foliage injury. All of the spray materials, with the possible 

 exception of neutral Bordeaux, reduced the size of the cherries. In most 

 years this was scarcely perceptible, but in 19 17 the dwarfing effect was 

 sufficient to cause considerable loss. 



The cherries of the Willamette Valley are often seriously damaged with 

 brown rot, yet during the five years' work at Salem there was not a 

 season in which the experimental orchard had as much as i per cent of 

 rot at picking time on either the sprayed or unsprayed fruit. 



Shipping experiments were made each year to determine the effect of 

 the orchard treatment upon the carrying quality of the cherries. One 



'Fisher, D. F. controi, op apple powdery mildew. U. S. Dept. Agr. Farmers' Bui. 1120, 14 p., 

 8 fig. 1920. 



• The formula is given in sulphur, lime, arsenic sequence: 85 parts sulphur, no lime, and 15 parts 

 arsenate of lead. 



Journal of Agricultural Research, Vol. XXII, No. 9 



Washington, D. C. Nov. a6, 193 1 



aaq Key No. G-ijt 



75308—22—2 (467) 



