116 HATCH EXPERIMEXT STATION. [Jan. 



Potato Rot. 



( Phyloph th ova ii if est a ns , DBy . ) 



The fungus mentioned above was also responsible to a 

 large extent for damage to potatoes, causing them to rot, 

 especially those grown on moist land. During the early 

 part of the season potatoes as a Avhole were remarkably free 

 from blight, and not until the rainy and damp i)eriod came 

 in September did they display any alarming trouljles. In 

 some instances quite a large percentage was destroyed by 

 rot. The spraying of potatoes in this State has not met 

 with that degree of success that it has in other New Eng- 

 land States, one reason being that the early blight often 

 occurs here quite disastrously, and ol)tains a foothold early 

 in the season. 



Spraying for this trouble should commence early in June, 

 Avhen the plants are about one-fourth grown, and continue 

 until late in the season. Another factor underlying success- 

 ful spraying is pressure ; at least 50 pounds' pressure should 

 be maintained by the pump, to secure the best results. Ex- 

 periments at the college this 3^ear showed material gain in 

 the quantity of potatoes secured from sprayed crops, as 

 compared with those not sprayed. 



Cucumber and Melon Blight. 

 The dry sunnnt^r with its freedom from moisture proved 

 lavorable for cucumbers and melons, and these crops were 

 not severely affected, at least previous to September, with 

 cither the downy mildew or anthracnose. During the past 

 fall there has occurred considerable infection to greenhouse 

 crops, especially those started early. For the last six or 

 seven years the downy mildew {PJamnopara Cuhensis (B. 

 &, C.) Humphrey) has occurred generally ui)on greenhouse 

 cucumbers started early in the house, and occasionally the 

 anthracnose {^CoUelotriclinm Lcifienarimn (Pass.) Ell. & 

 Hals.) api)ears in the fall, but we know of no instances 

 where cither of these blights has wintered in greenhouses. 

 Both of these blights must therefore at y)resent be consid- 

 erc(l as left over from sununer. The anthracnose, however. 



