The Soil and Leaf Nutrients Status on Main Production Areas of Low Chilling Requirement New Pear Cultivar 'Taichung No. 2' in Chinese Taipei

摘要

Leaf and soil nutrients of 22 orchards were analyzed to clarify the relationship between nutrients and storage disorder (watercore) of 'Taichung No. 2' pear new cultivar. Soil P2O5 content in 77% orchards were over the recommended amount, and 86% orchards have CaO content below proper level. Only 5 and 14% orchards have proper CaO content in leaves on non-fruited horizontal shoots and fruited spurs respectively. Mg deficiency was found in leaves of all orchards, whereas soil P_2O_5 content of most orchards is much higher than optimum level. Consequently, Ca/K and Ca/Mg ratio of leaves were dramatically below optimum level in all orchards. The same situation was also found in soil of most orchards. Watercore symptom was found in a quarter to 3/8 of fruits after stored for 1 month, and was found in all fruits after stored for 3 months. Calcium deficiency and low Ca/K and Ca/Mg ratio in soil and leaves may have some relationship with watercore occurrence.