32 .\rASS. EXPERnrENT STATION BULLETIN 378 



wet to begin with; but it caused some packing and puddling of soil which 

 was already too nearly saturated before treatment. 



Carnation Blight Caused by Alternaria dianthi S. & H. ( E. F. Guba, 

 Waltham.) Seedling carnations obtained from last year's breeding work 

 are now benched and growing in the greenhouse. As yet there is no indica- 

 tion that any of the seedlings are more resistant than the parents to either 

 Alternaria blight or branch rot caused by Fiisariiuii diantlii Prill. & Delacr. 



Control of Greenhouse Vegetable Diseases. . ( E. F. Guba and C. J. Gil- 

 gut, Waltham.) Observations on resistance of the Bay State tomato to 

 the tomato leaf-mold disease caused by Cladosporium fulvum Cke. were made 

 on crops grown under commercial conditions, in a number of greenhouses. 

 Under such conditions, this tomato showed 25 percent of the plants to 

 be susceptible to leaf mold while the remainder are highly resistant. 

 The Bay State tomato is highly pleasing to growers who in the past 

 have frequently experienced complete loss of their fall-winter crop due 

 to this disease. The yield has been found satisfactory. The one criticism of 

 growers is that the fruit does not ripen fast enough. 



The Bay State tomato is not a substitute for good greenhouse manage- 

 ment. In two establishments it was found that nearly all of the plants 

 had some mold on them. It was learned that the impression was prev- 

 alent among growers that the plants could be more or less neglected and 

 still remain free of mold. If managed as carefully as the highly susceptible 

 varieties of greenhouse tomato, the Baj- State variety, grown as a fall- 

 winter crop, is highly resistant to the leaf-mold disease and gives far 

 more satisfactory results. 



Factors Affecting Yield of Onions and Their Shrinkage in Storage. (C. 

 J. Gilgut and W. G. Colby. Cooperative with Agronomy.) Twenty-six 

 lots of onion sets were grown on typical Connecticut Valley onion soil 

 and compared for yield and shrinkage in storage. All lots were obtained 

 in the Valley, except six small lots for experimental trial which were 

 shipped direct from a mid-west producing area. 



There was less difference in performance of locally grown Japanese 

 seed sets and those shipped in than was the case last year. Locally 

 grown Japanese sets produced slightly higher yields than those shipped 

 in, but there was no significant difference in the yield of globe type seed 

 sets from different sources. 



After 90 days in storage, shrinkage resulting from disease averaged 17.8 

 percent for locally grown Japanese sets and 28.6 percent for three lots 

 of shipped in Japanese sets. The average shrinkage of globe type sets 

 was 24.5 percent for those grown locally and 25.7 percent for those shipped 

 in. However, the lots of globe type sets obtained for experimental trial 

 averaged 49.3 percent shrinkage. The large shrinkage loss in this case 

 can probably be accounted for by the fact that the sets were shipped in 

 airtight paper bags — the seed sets heated in transit and mold had developed 

 on the basal plates. The development of mold did not affect the growth 

 of these sets in the field. The average yield was highest of any globe 

 sets tested. 



In accordance with last year's results, it was found tliat in the early 

 part of the storage period bacterial soft rot predominated, while later 

 Fusarium bottom rot was more prevalent. 



In harvesting experiments onions pulled, clipped, and stored the same 



