14 BULLETIN 856, U. S. DEPARTMENT OF AGRICULTURE. 



parison with its behavior when growing as an entire plant on its own roots. To 

 illustrate, the table shows that as to congeniality the Panariti when grafted on 

 Amnion X Itupestris Ganzin No. 1 was rated at 96, when on Dog Ridge at 93, 

 and when on Salt Creek at 85. This shows that the Panariti variety, which is 

 well adapted to the conditions in the Fresno Experiment Vineyard, when grafted 

 on these stocks at the same time under the same conditions, with the same 

 treatment in the same vineyard, varied in growth and behavior in comparison 

 with the variety on its own roots in accordance with the above ratings. 



Columns 3 and 4 show the earliest and the latest date of starting into growth 

 and of blooming, respectively, on the 10 stocks during the 10 years. These data 

 are given as a basis of comparison with other grape varieties growing in the 

 same locality. As the vines must be ringed while they are blooming, the blossom- 

 ing data also indicate the time of year when the ringing must be done. 



Column 5 shows the earliest and the latest date of fruit ripening on the 10 

 stocks during the 10 years. This serves to show that currant grapes can be 

 grown in advance of other raisin grapes and that they may be sun dried before 

 the fall rains start in districts where other raisin grapes ripen too late. 



Columns 6 and 7, respectively, show the yield of fruit per vine that the 

 Panariti check vines bore in 1917 on each of the 10 stocks, compared with the 

 yield of fruit per vine borne by ringed Panariti vines on the same stocks grow- 

 ing side by side, with otherwise the same care and treatment given them the 

 same year. 



Columns 8 and 9, in like manner, afford a comparison of the yields of fruit 

 in 1918. 



Columns 10 and 11 compare the sugar content (Balling scale) of the fruit of 

 the Panariti variety on each of the 10 stocks in the years 1917 and 1918, 

 respectively. 



Columns 12 and 18 compare the acid content (grams per 100 c. c.) of the 

 fruit of the Panariti variety on each of the 10 stocks in the years 1917 and 191S l 

 respectively. 



Table IV shows the relative behavior of two young Panariti vines 

 (ringed), each growing on 15 additional stocks, during a 4-year 

 period, the vines being trained to a trellis. Explanations similar to 

 those given for the same columns in Table III apply to columns 1 to 5 

 in Table IV. Columns 6 and 7 show the relative quality and yield 

 of fruit of the Panariti vines on each of the 15 different resistant 

 stocks. 



The data in Table IV relating to the behavior of young Panariti 

 vines trained to a trellis for only two vines each on 15 resistant-stock 

 varieties do not allow a fair comparison with data in Table III of the 

 behavior of older vines trained to stakes, but promises of larger 

 yields with trellis training are indicated. More elaborate tests of 

 these and other stocks are now under way to obtain more con- 

 clusive data as to congeniality. 



The results of the ringing experiments for 1919 have not been 

 compiled as yet. It is known, however, that they corroborate and 

 strengthen tha results obtained in 1917 and 1918, and that the actual 

 yields in 1918 were fully 10 per cent heavier than those of 1917, when 

 the heaviest crop that up to that time had been grown was obtained. 



