EFFECT OF ALAR AND NITROGEN FERTILIZER TREATMENTS ON GROWTH, YIELD AND QUALITY OF STRAWBERRY
There was early flowering and higher yield by using 1 g N per plant and no alar, and a considerable delay of flowering and yield reduction by giving the plants 2 g N due to the excessive foliage burning following application. This treatment when coupled with 2000 ppm alar resulted in good fruit set but heavy botrytis infection and so the lowest marketable yield. Plants treated with no alar gave significantly more fruit number, more fresh fruit yield and more fruit dry weight as g/plant than either of the other alar treatments, but 2000 ppm gave significantly higher percent fruit dry weight. The higher nitrogen fertilizer rate increased the percent of fruit dry weight particularly in the late season sampling. With the exception of this treatment the percent was highest in the mid-season sampling for all treatments. Vegetative runners tended to increase gradually with the increase of nitrogen and alar. Total soluble solids of fruit juice was reduced by nitrogen fertilization and spray of 2000 ppm alar.
These results indicate that for highest yield the best treatment is 1 g N/plant and no alar, while for highest percent of fruit dry weight the best concentration of alar is 2000 ppm and that the mid-season harvest provides the best fruits.