Foliar-applied boron （B） to prevent B-deficiency in red bayberry（Myrica rubra）

Key words: 
• horticulture /
• red bayberry（Myrica rubra） /
• boron deficiency /
• foliar application /
• boron spray concentration /
• boron spray timing /
• boron application method

Abstract: Red bayberry（Myrica rubra），a fruit tree，is very sensitive to boron （B）-deficiency. Three trials were conducted in Zhejiang Province to study the response of red bayberry to foliar B application and to determine the optimum period of application. Treatments included application to：soil + foliar B，foliar B，and soil；foliar-applied：1） B and B plus：2） urea，or 3），urea and KH2PO4；and timing of the spray：autumn（5 August of 2002），before blossoming（5 March of 2003）or full flowering day（20 April of 2003）. Each treatment had four replications. After treatment，fruit setting rate，fruit weight，length of branch sprouted in spring，concentration of N，P，K，and B in leaf were determined. Results showed that foliar-applied B not only significantly（P＜0.05）improved sprouting of spring and summer shoots，but also significantly（P＜0.05） increased fruit yield and improved fruit quality. Different B applications on fruit yield and quality of red bayberry showed：soil application + foliar B application ＞ foliar B application ＞ soil application. Urea or urea + KH2PO4 added to a foliar B application not only significantly（P＜0.05）increased tree uptake of B，but also significantly（P＜0.05） increased yield. Overall，foliar-applied B was found to be an effective method to correct B-deficiency of fruit trees with the optimum growth stage（before blossoming or full flowering days） for application being at full bloom.［Ch，5 tab. 18 ref.］