Effect of Soil Moisture and Calcium Deficiency on Incidence of New Branch Necrosis and Tip-Burn in Jujube (Zizyphus jujuba Mill.)

Abstract

Jujube (Ziziphus jujuba Mill.) is the most important native species of Rhamnaceae, a large cosmopolitan family, and is one of the oldest cultivated fruit trees in the world. In recent years, consumption of fresh fruit and big fruit jujube has increased. The purpose of this study was to investigate the causes and its alleviation techniques of new branch necrosis and tip-burn, which occur in jujube during the new branch growth period. As a result of analyzing the inorganic component content of leaves, the calcium content was markedly 1.48% of abnormal samples compared to 1.90% of normal samples appeared low. Also, the calcium content in a necrotic new branch was also 0.14%, which was very low compared to 0.76% in the normal sample. In addition, the incidence rate of tip-burn at -30 kPa by soil at starting point of irrigation was 16.53%, higher than 7.22% at -10 kPa. The incidence of tip-burn by calcium foliar application was 0.6%, which was very low compared to control of 4.3%. Therefore, this study suggests that the symptoms of necrosis of new branch and tip-burn that occur during the new branch growth period of Jujube are related to the calcium content in the plant and lack of soil moisture and that calcium foliar application is effective in alleviating the occurrence of these abnormal symptoms.Alleviation effect of leaf tip-burn by Ca foliar application.