Some of the information given in the section of this report [cf. R.A.M., 34, p. 628] dealing with new or noteworthy diseases (pp. ii-v) [also given in French] has already been noticed [see preceding abstract]. The susceptibility of wheat varieties grown in western Canada to the prevailing races of leaf and stem rust (Puccinia triticina and P. graminis) [loc. cit.] is emphasized, as increasing losses are being suffered, especially in durum wheats. In Ontario several of the winter wheat areas were affected by dwarf bunt (Tilletia controversa) [loc. cit.], while eye spot (Cercosporella herpotrichoides[Pseudocercosporella herpotrichoides]) [30, p. 307] was found in several fields. A viras disease of wheat, oats, and barley in Alberta may be caused by the cereal yellow dwarf virus [33, p. 74].
The replacement of Grimm lucerne in southern Alberta by Ladak, partially resistant to bacterial wilt (Corynebacterium insidiosum) [see preceding abstract], lessened the destructiveness of the disease. The occurrence of G loeosporium spadiceum on red clover in Quebec constituted a new record for eastern Canada. Downy mildew of sunflower (Plasmopara halstedii) [loc. cit.] was more severe during the period under review.
Phytophthora megasperma caused a new field rot of carrots [cf. 32, p. 413] in British Columbia.
The incidence of bacterial ring rot (Corynebacterium sepedonicum) on potato [see preceding abstract] depended upon the control measures taken by various provincial authorities. Blight (Phytophthora infestans) [loc. cit.] was present on potato in every province for the third year in succession. The new European latent virus disease, caused by potato virus S [cf. 34, p. 807], was detected sero-logically in Green Mountain potato plants at Fredericton, New Brunswick.
During 1953 pear blast (Pseudomonas syringae) [34, p. 793] was epidemic in the Saanich peninsula, British Columbia, but was less prevalent in 1954. Strawberry red stele (Phytophthora fragariae) [see preceding abstract] was found for the first time in the Niagara peninsula.
Among new records of interest on trees and shrubs were the leaf-spotting fungi Marssonina betulae on birch (Betula papyrifera), a new record for North America, and Actinopelte dryina on oak (Quercus borealis[Quercus rubra]), a new Canadian record.
In a greenhouse at Regina, Saskatchewan, chrysanthemum topple (non-parasitic) was severe. New Canadian records on ornamental plants included Xanthomonas oryzae var. dianthi on carnation [33, p. 724], Septoria lythrina on the Lythrum variety Morden Pink, and Cryptosporium minimum on rose [cf. I4, p. 171].