Breeding poplars for disease resistance. Thielges, Bart A. Food and Agriculture Organization of the United Nations. Poplar Poplar 634 FOO 1985 A053 Or. "This paper, prepared ... by Professor B.A. Thielges ... was presented as a background paper to the ad hoc Committee on Poplar Breeding during the 17th Session of the IPC at Ottawa, Canada, in October 1984"--P. iii. Rome : Food and Agriculture Organization of the United Nations, 1985. 1985. Text vi, 66 p. :