Treatment approved for seed potatoes

Press, Volume CXV, Issue 33883, 1 July 1975, Page 18

Treatment approved for seed potatoes

A fibreglass swimming pool, 12ft by 12ft, filled with a sodium hypochlorite solution, may be used to help the hard-pressed potato growers now facing a crisis to their livelihood.

The Ministry of Agrii culture has approved the sale of certified seed potatoes from properties affected provided they are submitted to a twohour soak in the solution.

A Ministry spokesman said the department was sure that potatoes so treated would be 100 per cent free of the pest. They will be subject to inspection and the issue of a certificate of health.

Approval of the use of this method of treating seed potatoes follows the finding of Dr F. Wood, of the Plant Diseases Division of the Department of Scientific and Industrial Research in Auckland, that the chemical,' which is an ingredient of a wellknown bleaching material, kills the pest in a soak treatment. Use of the treatment will allow seed growers to continue in their usual business, but subiect to some restrictions. These include the retirement of infested land from the growing of crops such as potatoes and tomatoes, and they will also have to comply with hygiene requirements. TO DO TREATMENT The Ministry will conduct the treatment and would like to see it in operation in three weeks. It appears as though the costs of the treatment will be between about $l2 and’sls per ton and this will be charged to growers. In addition, the treatment will involve the grower in some effort or cost in preparing the potatoes for treatment and he will also have to repack them afterwards. The Ministry spokesman said that there would be some practical problems involved in the treatment. The chemical can be obtained in bulk deliveries from New Zealand Forest Products at Kinleith. It is likely that it will be stored in a butyl pillow tank of at least 2000

gallons capacity and the chemical, which will be used at a 1 per cent concentration, will be carried on a motortruck or trailer to the treatment site in a smaller 200gallon butyl pillow tank, which will be filled by gravity. The effect of the sodium hypochlorite on the butyl is now being studied.

Tests on potatoes treated with the chemical have shown no adverse effects on generation to date. The Ministry is also studying the use of the soak treatment for table potatoes.

The nematode has now been found on three properties in the potato seed areas in the Halkett and Waddington districts.