Potassium Sulfate Produces a 

 Higher Quality Potato Than Potass- 

 ium Chloride. The average consum- 

 er of potatoes in New England pre- 

 fers a "mealy" or high-starch potato. 

 The New Hampshire Agricultural Ex- 

 periment Station has been studying 

 the source of potassium as a factor 

 influencing the specific gravity of po- 

 tatoes ( Specific gravity and starch 

 content are closely associated.) As a 

 result of work conducted in the field 

 at Northwood Ridge and Colebrook 

 as well as greenhouse tests at Dur- 

 ham, no other conclusion can be 

 drawn but that if the potassium in 

 the fertilizer mixture is supplied in 

 the form of potassium sulfate the 

 potatoes are of superior quality as 

 compared to those fertilized with a 

 mixture in which the potassium is 

 supplied as potassium chloride. It 

 appears that the differences are suffi- 

 ciently great so that some of the new- 

 er disease-resistant varieties of only 

 fair cooking quality, by fertilization 

 with potassium sulfate, may be im- 

 proved sufficiently in quality to per- 

 mit its adoption by the commercial 

 grower without sacrificing quality. 



F. S. Prince, P. T. Blood, 



L. T. Kardos 



Ontario and Essex are Proving to 

 be Excellent Potato Varieties for New 

 Hampshire. Although some 23 var- 

 ieties of potatoes are being tested, 

 many of them either need further 

 study or are definitely unsuited to 

 our conditions. We are seeking a 

 variety with the eating quality of a 

 Green Mountain and which yields 

 well and has disease-resistance. The 

 Ontario approaches this ideal more 

 closely than any other variety that 

 has been tested at this Station. It 

 is highly resistant to potato scab, 

 has some resistance to late blight, 

 yields well, and is of good quality, 

 being definitely superior to such 



varieties as Katahdin, Sebago, and 

 Chippewa in the last respect. 



Another variety that should have 

 an important place among the var- 

 ieties is the Essex. This is one of 

 the blight-resistant varieties devel- 

 oped at Cornell University. It is a 

 consistent high yielder having ranked 

 among the top three varieties ever 

 since it was first introduced into our 

 plots. It is a nice appearing, white- 

 fleshed potato. Its only drawback is 

 that it is low in specific gravity and 

 hence does not have the good baking 

 quality that is so much desired. On 

 the other hand, the fact that it yields 

 high, whether or not the season is 

 cool or warm, wet, or dry, is a strong 

 point in its favor. 



P. T. Blood 



Sprout Inhibitor Lengthens the 

 Marketing Period for Potatoes. 

 About 200 bushels of Kathadin pota- 

 toes were treated with a sprout in- 

 hibitor (a methylester of naphthaline- 

 acetic acid ) at the end of the rest 

 period during the last week in March. 

 The inhibitor was used according to 

 the manufacturer's directions, one 

 pound of 2.2 per cent dust to 11 

 bushels of potatoes. These potatoes 

 remained in storage until the latter 

 part of July and were still in a sala- 

 ble condition. None of the sprouts 

 had developed to such an extent as to 

 require their removal. The loss in 

 weight during this period averaged 

 only 3.17 per cent. 



This method of dusting potatoes 

 offers excellent possibilities to those 

 who wish to market potatoes during 

 the entire 12 months. The late fall 

 crop can be left until the early po- 

 tatoes are ready for harvest the next 

 year. Those interested can contact 

 their Agricultural County Agent in 

 regard to where the sprout inhibitor 

 may be purchased. 



P. T. Blood and L. T. Kardos 



10 



