LEMON STEM ROT.

Auckland Star, Volume LXIV, Issue 253, 26 October 1933, Page 22

LEMON STEM ROT.

During the canvass for lemons for the advertising scheme last month, in company with Mr. Peters, of the New Zealand Fruit Growers' Federation staff, a number of lemons were noticed affected with lemon stem rot. To ascertain definitely the cause and the treatment, samples were forwarded to Dr. G. H. Cunningham, mycologist, Department of Agriculture, plant research station, Palmerston North. Under date of October 13 Dr. Cunningham reported as follows: "Cultures have been made from the lemon fruits forwarded by you on the 25th instant. From these we have secured a fungus which has been identified as phompsis citri, the cause 6f the stem rot in California and elsewhere. The fungus appears to, enter through the stem end- Its control consists of (a) removing all dead laterals from the tree; (b) spraying with the usual 3 —4—50 bordeaux sprays at spring and autumn; (c) keeping fruits at temperatures as low as possible, 40-50 decrees F., as the fungus thrives in a humid, warm atmosphere; (d) discarding at the time of picking all fruits showing stem injury." As I have noticed that stem rot is in evidence in many places, I have thought that this information from Dr. G-. H. Cunningham may prove of considerable value to lemon growers. GEO. A. GREEN.