RELATION OF POTASH TO POTATO BLIGHT.

Colonist, Volume LIV, Issue 13411, 8 May 1912, Page 8

RELATION OF POTASH TO POTATO BLIGHT.

Tli© requirement of the potato crop for n liberal supply of available potash is well known, and is acted upon by the most successful growers. When large quantities of farmyard manure are given, it may not be necessary to apply chemical potash, but it is generally now reoogiuGied that the more} iprofitable. method of cultivation is to use more rnodoraio quantities of farmyard manure and to supplement it with artificials; in such easos liberal proportions of potash should ho included.

An-nthor advantage of potash may also be mentioned. It has been proved that it enables the tuber to resist the stacks of blight. This is shown by the following experiment.

The potatoes in an experimental field were carefully sprayed with Bordeaux mixture, tho dates of the successive applications being June 27, July 7, and August 10.

Early in August it was noticed that the leaves of al" the no-potash plants -.vere- beginning to be blighted whil« tho foliage on all the plots to which potash had boon applied still appeared to bo practically unaffected. Tho blight made rapid progress on each of the five no potash plots, while the foliage of the plants in^the potash plots for the most part ripened normally. Practically all tue loaves on the no-potash plots wore dead by the end of August, at which date there was considerable living foliago on the potash plots. The marked inferiority in yield cf the noVpotash plots was, no doubt, in considerable measur« due to the relatively early death of the foliage.

Other observers, among them Dr Goessmann and Professor Maynard, have also held that a liberal supply of potash exercised a marked influence in •enabling the foliage of fruits to resist fungous diseases.