ChileanJAR

In 20 yield trials with 27 varieties each and 4 replications, the frecuency of the "dry leaf tip" character was determined. For this, each plot was classified in three categories a) no dry leaf tip (grade 0); b) less than 20% dry leaf tip (grade 1); c) more than 20% dry leaf tip (grade 2). The sums of the grades of the four replications is the final grade for each variety. Grades varied between Oand 8. The varieties were grouped according to these grades in 5 clases: Class 1 = grades Oand 1; 2 = 2 and 3; 3 = 4 and 5; 4 = 6 and 7; and 5 = 8. There were 320 varieties in class 1; 32 in 2; 24 in 3; 45 in 4; and 18 in 5. The yield average of the varietiesin c1ass 1, without this defect, was compared with the rest of the varieties with varying amount of dry leaftip. Class 1 had a 98.6% yield average (with respect to the 5 checks) and the rest of the varieties had a 89.4% yield average. The loss of the varieties with dry leaf tip was 9%; this difference is significative tol%.