Cracked Stem In Celery: Borax Cure Proves Effective

Bay of Plenty Beacon, Volume 13, Issue 71, 30 March 1949, Page 7

Cracked Stem In Celery: Borax Cure Proves Effective

Celery growers of New Zealand have sometimes experienced losses as high as 80 per cent on particular pieces of ground because of stem cracking of the plants. It has been found that losses may vary widely from season to season, but where the damage has been heavy some growers have been forced to abandon celery growing because it has proved uneconomic, says a bulletin from the Department of Scientific and Industrial Research.

The presence of the disease is first noticeable when the crop is about half-grown, the stems become more brittle than normal and small transverse breaks appear in the epidermis immediately above the ribs of the tallest stems. As the plant develops, the growth is stunted roughly in proportion to the number of breaks, and where few breaks 'occur, narrow strips of tissue curl back from the sides of the fractures. Root systems of affected plants are coloured light brown instead of clean white, and scattered sparsely over the larger roots are small orange-coloured patches of tissue that flake away readily. Investigations made by the Plant Diseases Division of the Department of Scientific and Industrial Research showed that cracked-stem in celery is due to a deficiency of borax, and that by making good the deficiency the amount of injury was reduced from 87 per cent to 1 per cent.

In about six weeks after planting, untreated plots showed an average of/33 per cent of plants slightly cracked and 54.3 per cent plants severely cracked. The plots dressed with borax showed no severely cracked plants, and the average of slightly cracked plants was 1.3 per cent for plots dressed with 401 b of powdered borax to the acre, and 0.8 per cent for plots sprayed with 201 b of borax to the acre dissolved in water. No sign of plant injury attributable to borax was seep at any stage of growth. An attempt was made to determine the effect of borax on yield, but unfortunately extensive , weed growth throughout the area made it impossible because of irregular development of the celery. One portion of the block, however, remained comparatively free from weeds, and here the treated plants were. visibly larger than adjacent untreated plants. On a grading to local market standards all the sticks from a treated plot (401 b per acre) were first grade, and from an adjoining untreated plot there were 41 per cent first grade, 35 per cent second grade, and 24 per cent valueless.