Effect of Mother Stem Training on Spear Quality and Yield of Asparagus (Asparagus officinalis L.) in the Greenhouse

Abstract

This study examined the effects of mother stem training on spear quality and yield of asparagus (Asparagus officinalis L.) in the greenhouse. The training was performed with the “mother stem bending method” (Sakamoto et al., 2011). No significant differences were found in the diameter, soluble solid content, firmness, and index of spear tightness of asparagus spears between the untreated group and the mother stem training treatment group. However, the mother stem training method was effective in improving the spear color quality owing to the increase in incident light intensity. On the other hand, the mother stem training treatment resulted in a decrease in the fresh weight of the spear, marketable yield, and marketable yield ratio of the LL (over 33 g) spear size when compared to that of the untreated group. The cause of this decrease in summer yield in the treated group was hypothesized to be a failure in nutrient translocation and low light interception in close proximity to the other stems.