12 BULLETIN 856, IT. S. DEPARTMENT OF AGRICULTURE. 



ringing. Hence, ,the entire vine is affected by one ringing of the 

 trunk, but when either arms or canes are chosen all of them must be 

 ringed, in order that the entire vine may be affected. 



In the experiments conducted at the Fresno Experiment Vine- 

 yard, 12-year-old ringed Panariti grafts on 10 different resistant 

 stocks trained to stakes (vines 8 by 8 feet apart, or 680 to the acre) 

 during 1917 and 1918 gave average annual yields per acre ranging 

 from about 5.8 tons (PL IV, fig. 1) on the poorest stock to 10.35 

 tons on the best stock, the average on all the stocks being nearly 7| 

 tons. The check vines with like treatment and care averaged only 

 2£ tons to the acre (PI. IV, fig. 2). Ringed 5-year-old Panariti 

 grafts on 18 different resistant stocks, with trellis training (vines 

 8 by 8 feet apart, or 680 to the acre) during 1917 and 1918 averaged 

 annually over 5 tons to the acre, while the check vines averaged only 

 1.9 tons to the acre. 1 



CONGENIALITY OF THE PANARITI VARIETY TO PHYLLOXERA- 

 RESISTANT STOCKS. 



In the belief that an important new grape industry can be de- 

 veloped from the dried fruit of the Panariti grape, and that it is 

 destined to play an important role in Vinifera viticulture, this 

 variety was one of those selected for extensive tests of the con- 

 geniality of Vinifera grape varieties to the important phylloxera- 

 resistant stocks at the Fresno Experiment Vineyard in California. 



In a 10-year test of the Panariti variety grown on various resist- 

 ant stocks, a sufficient number of varieties of these stocks have been 

 found from which to select those which are adapted to any of the 

 types of grape soil, as well as to other conditions which are congenial 

 to the currant-grape varieties and on which they show a tendency to 

 good fruiting. 



The data given in Table III show the relative behavior of Panariti 

 vines growing on 10 different phylloxera-resistant stocks in the 

 Fresno Experiment Vineyard. Ten vines each of the Panariti grape 

 grafted on the Lenoir, Rupestris St. George, Riparia Gloire, Salt 

 Creek, and Dog Ridge were included in the tests. Of each group of 

 10 vines, 2 were check vines, 4 were vines with canes ringed, and 

 4 were vines with trunks ringed. Five vines each of Panariti 

 variety grafted on the Adobe Giant, Aramon X Rupestris Ganzin 

 No. 1, Mourvedre X Rupestris No. 1202, Riparia X Rupestris No. 

 3309, and Solonis X Riparia No. 1616 were also included in the tests. 

 Of each group of five vines, one was a check vine, two were vines 



1 For further Information on the adaptability of resistant stocks to soils and other 

 ■ onditions see Bureau of Flant Industry bulletin 172, entiltcd " Grape Investigations in 

 the Vinifera Regions of the United States with Reference to Resistant Stocks, Direct 

 Producers, and Vinifcras," and Department of Agriculture Bulletin 209, entitled " Test- 

 ing Grape Varieties in the Vinifera Regions of the United States." 



