80 MASS. EXPERIMENT STATION BULLETIN 355 



This year 1140 accessions have been added to the collection making a total of 

 2485, a sufficiently comprehensive number from which definite recommendations 

 as to their rating will be made. 



Intensive study has been given to 8 varieties of Aubrieta, 31 varieties of Del- 

 phinium, 35 varieties of Heuchera, 31 varieties of Dwarf Iris, 72 varieties of 

 Lilium, 40 varieties of Papaver orientale, and 38 varieties of Tulipa (species). 

 As evidence of the merits and faults of the various members of these groups is 

 obtained, their ratings which have previously been undefined are becoming 

 established. 



DEPARTMENT OF OLERICULTURE 

 Grant B. Snyder in Charge 



Shape Index Studies of Tomatoes. (W. H. Lachman.) Studies in previous years 

 indicated that shape indices were quite reliable for making quantitative compari- 

 sons among varieties of tomatoes. Shape indices, therefore, would appear to be 

 a valuable tool where satisfactory comparisons of varieties are necessary and to 

 ascertain whether progress is being achieved in type improvement during the 

 course of a tomato breeding project. 



These studies have been continued and have been made to include the effect 

 of soil variability upon the shape of tomato fruits as well as climatic influences 

 on the modification of form. Yield records also have been obtained in an effort 

 to determine how large the yield differences among varieties must be in order 

 to be significant. 



On the basis of the records of one year, a difference in yield of 30 percent was 

 found necessary to indicate significance. 



Sweet Corn Breeding. (W. H. Lachman.) More than 1600 plants of eight 

 varieties of sweet corn have been inbred in an effort to isolate pure lines which 

 excel in uniformity of earliness, productivity, disease resistance, and quality. 

 Two hundred of these inbreds show a moderate to high degree of resistance to 

 bacterial wilt as well as freedom from lodging during the period of maturity. 



Soil Preparation for Vegetables. (VV. H. Lachman and G. B. Snyder.) Tillage 

 methods prior to seeding or plant setting in the field is considered important by 

 vegetable growers. During the past summer a comparison was made between 

 normal tillage and rotary tillage, to stud>' their relative merits in the incorpora- 

 tion of organic matter in the soil and their influence upon availability of nutrients 

 as well as upon yield and quality of several vegetables. Abnormal weather 

 conditions during the summer appear to have masked any significant differences 

 which might have been displayed during a normal growing season. 



Tomato Breeding. (W. H. Lachman.) Most commercial varieties of tomatoes 

 have a green to yellow-red coloration of the shoulders when firm ripe. This 

 character is undesirable from both the fresh market and can-house viewpoint. 



Genetical studies involving several uniform ripening strains and four com- 

 mercial varieties of tomatoes have been carried to the second generation. The 

 selections made, while all determinate in growth, are very promising in combin- 

 ing earliness, yield, quality, and uniform ripening. 



Cultural Practices Prior to Field Setting as Influencing Yield and Quality of 

 Peppers. (W. H. Lachman.) The yield of early peppers is of vital importance 

 to the market gardener. Methods of handling plants prior to field setting were 



