26 



MASS. EXPERIMENT STATION BULLETIN 339 



insulation of the building, adequate means of ventilation, and more accurate 

 and reliable control over heating. 



The disinfection of the squash in storage after harvest by fumigating with 

 formaldehyde offers an attractive substitute for the obnoxious formaldehyde 

 dip treatment. A periodic disinfection of the squash in storage with formal- 

 dehyde gas suggests a practical means of controlling decay. Details and dosages 

 will be given further study. 



As the result of extensive artificial inoculation of squash in the field and 

 after harvest with decay organisms from pure culture, it is apparent that (1) 

 injuries predispose the squash to infection; (2) infection becomes increasingly 

 successful at points of injury as the life of the squash cells required to produce 

 callus is lost; (3) cessation of callus growth is correlated with or followed by 

 vital chemical changes which render the squash a favorable nutrient medium 

 for the growth of decay organisms; (4) a distinct correlation exists between size 

 (maturity) and decay. 



Field applications of Bordeaux and copper-lime dust were made on two 

 distinct areas of squash in the field. Cne area was left untreated. No contrasts 

 were apparent. Such applications were not considered practical beyond mid- 

 summer. 



At harvest the following treatments were compared: (1) formaldehyde dip, 

 (2) pre-storage in the field under vines, (3) careful handling, (4) cutting the 

 stems short, (5) rough handling, (6) fumigation with formaldehyde. The 

 results are not yet available. 



Miscellaneous Tests and Experiments. (C. J. Gilgut and E. F. Guba, 

 Waltham.) Frequently, in the field of plant disease control, results obtained 

 by investigators in other localities appear to be applicable to use in this State. 

 Often, however, it seems desirable to test such results under our own conditions 

 before recommending them to growers. The following tests in part were carried 

 on for that purpose. 



1 . Vegetable Seed Treatments. Dry chemical seed treatments for controlling 

 damping-off were limited to red copper oxide, zinc oxide, Semesan, and Semesan 

 Jr. The results, collated with the work of previous years, are summarized in 

 the following recommendations. 



2. Tests of Fungicides on Field Tomatoes. Spray tests were made of various 

 proprietary and homemade fungicides on tomatoes to determine the effect on 

 foliage, yield, and disease control. Ten applications were made at 7 to 10 

 day intervals beginning on June 23 and continuing to September 2. 



Materials used, percentage content of metallic copper, and strength of appli- 

 cation were, Market Garden Copper (11 percent) 1 part in 128 parts of water; 



