EXPERIENCES WITH NEW PEAR ROOTSTOCKS

New pear rootstocks are being selected at the Fruit Research Station at Angers. These belong to the species Pyrus communis L. From the 80 clones set up in 1971, 16 are of interest because of the growth vigour and productivity they induce in pear cultivars. According to growth vigour five groups have been established. The average vigour of trees on rootstocks in these groups as a percentage of that on Quince A is:

Group	I	28
Group	II	42.5
Group	III	69
Group	IV	100
Group	V	122

Productivity on the most interesting clones is superior to that on Quince A by 40 to 90 %, and the least vigorous ones are likely to be of interest for high density plantings.