Effect of time of closing and paclobutrazol (PP333) on seed yield of ‘Grasslands Puna’ chicory (Cichorium intybusL.)

Abstract

Defoliating ‘Grasslands Puna’ chicory (Cichorium intybus L.) after October severely reduced seed yields. In 1984–85 there were no significant differences in seed yield between closing (date of last defoliation) at the beginning of May, August, September, or October. The highest seed yield, 282 kg/ha, was from a September closing. In 1985–86 the May closing produced the highest seed yield, 228 kg/ha. In general stem populations appeared to be the most important component of seed yield, particularly in the early closed crops. Stem populations tended to decrease with the age of the crop. Earlier closing gave a more concentrated flowering and made harvesting easier to judge. The plant growth regulator paclobutrazol had no effect on seed yields. From October onwards Puna chicory accumulated herbage very rapidly, over 200 kg dry matter/ha per day.