116 PROTECTION OF PLANTS — 1923-24 



young worms could doubtless be destroyed by a thorough application of arse- 

 nate of lead, 23^ or 3 lbs. in 40 gals, of water or dilute lime sulphur solution. 



Sanders and Dustan (1) offer the following advice. The height of emergence 

 takes place when the blossoms are showing pink. Therefore, in serious outbreaks 

 the spray should be applied just before the blossoming period. The calyx spray 

 is also important and in both applications high velocity, drenching sprays 

 should be applied. Arsenate of lead 5 lbs. to 40 gals, of water or dilute lime 

 sulphur solution is the most satisfactory mixture. 



According to Sanders and Dustan, (2) "The most important natural 

 means of control are wind and rain which cause immense numbers of the 

 larvae to drop to the ground and perish during the first two weeks of their 

 existence". 



THE STRIPE OR STREAK DISEASE OF TOMATOES IN QUEBEC. 



T. C. Vanterpool, Depo;. of Botany, Macdonald College. 



Introduction. 



Early in the spring of 1923 the tomato crop in the commercial greenhouses 

 at Macdonald College became infested with a disease which was characterised 

 by a long spindling growth of the upper part of the plants, a spotting, curling 

 and shrivelling of the leaves, small irregular brown spots on the fruit, and brown, 

 oblong, sunken markings on the stem and petioles. 



On examining the literature it was found that the disease resembled most 

 closely one which has been reported on under a variety of names, and concern- 

 ing which investigators differ in their opinion as to the etiology. 



Previous Investigations. 



The first account of such a disease was given by Bailey (1), in 1892, when 

 he reported a blight of winter tomatoes which corresponds in many details 

 with the outbreak here in Quebec, except that he found no spotting on the fruit. 

 To this he ascribes the name "Winter Blight of Tomatoes". He was unable to 

 determine the specific cause of the malady. 



Five years later Selby (2), from Ohio, described a blight of forced tomatoes 

 with symptoms similar to those described by Bailey, but he reports a spotting 

 on the fruit. He was unable to find any organism associated with the diseased 

 tissue; whereas Bailey mentions that a micrococcus was found in the diseased 

 parts. 



In 1916, the disease was first reported from Canada by Howitt and Stone 

 (4). Repeated trials to isolate a causal organism from the diseased tissues 



1. — Sanders & Dustan, Loc. cit. p. 15. 

 2. — Sanders and Dustan, Loc. Cit. p. 16. 



