280 MUTATION AND PLANT BREEDING 



Table 2. — Continued. 



Grapes: 



Dormant buds, 2,000 to 3,000 r, Breider, 1956; Olmo, 1960 



Roses: 



Summer buds, 5,000 to 10,000 r, Gelin and Gustafsson, unpublished 



Black currants: 



Dormant wood cuttings, 3,000 r, Bauer, 1957 

 Blackberries: 



Leaf bud cuttings, 4,000 to 6,000 r; dormant seeds of apomictic species, 10,000 to 20,000 

 r, Koch and Nybom, unpublished 

 Raspberries: 



Spring suckers, 10,000 to 12,000 r, Nybom, unpublished 

 Potato: 



Resting tubers, 3,000 to 4,000 r, Asseyeva, et al., 1935; Hagberg and Nybom, 1954; 

 Heiken, 1960; Howard, 1958 

 Sweet potato: 



Leaf cuttings, 3,000 to 4,000 r, Nishiyama, et al., 1959; root-tubers, 2,500 to 15,000 r, 

 Matsumura and Fujii, 1957 

 Tulips and Hyacinths: 



Dormant bulbs, summer or early fall, 800 r, X-rays, de Mol, 1944; 2,000 to 5,000 r, 

 gamma, semi-chronic, Carlsson, unpublished 

 Chrysanthemum : 



Stem cuttings, 1,000 to 2,000 r, Jank, 1957 

 Carnation: 



Stem cuttings, 5,000 r, Sagawa and Mehlquist, 1957 



Growing plants, 200 r/day, 105 days, Richter and Singleton, 1955 

 Camphor tree: 



Seedlings and cuttings, 2,000 to 6,000 r, Matsumura and Fujii, 1957 

 Coffee: 



Growing plants, 20 to 100 r/day, several months; seeds, 10,000 to 20,000 r, Moh and 

 Orbegoso, 1960 

 Saintpaulia: 



Leaf cuttings, 2,000 to 3,000 r, Sparrow and Konzak, 1958 

 Various Bulbs and Corms: 



5,200 r, Spencer, 1955 

 Alfalfa: 



Rooted cuttings, 3,000 to 4,000 r, Murray, 1956 

 Antirrhinum: 



Shoots, up to 250 r/day; Cuany, et al., 1958 

 Nicotiana: 



Rooted cuttings, 50 to 200 r/day, several months, Sand, et al., 1960 

 Poa pratensis: 



Apomictically produced seeds, 20,000 to 30,000 r, Julc'n, 1954 



In most cases slight modifications of the propagation methods 

 commonly used for the plants in question seem easily applied for 

 irradiation of the material. That large variations in the frequency 



