Selection of Acid-tolerant Rootstocks and Grafting Combinations of Olea europaea Cultivars

Experiments were conducted on acid tolerance and rooting capacity of 15 cultivars of Olea europaea, such as O. europaea ‘Arbequina’, O. europaea ‘Chenggu 32’, etc. in Hangzhou, Zhejiang province. The result demonstrated that O. europaea ‘Zhengyun’ and O. europaea ‘Zhonglan’ showed better root growth (hydroponics), high survival rate, seedling growth rate (pot culture) and rooting rate under acid stress. Using ‘Zhengyun’ and ‘Zhonglan’ as rootstocks, six other cultivars were grafted respectively. The test showed that ‘Fecciaro’ and ‘Arbequina’ with ‘Zhengyun’ as rootstock, ‘Taggiasca’, ‘Frantoio selezione’ and ‘Nichiskii Ⅰ’ using ‘Zhonglan’ as rootstock, ‘Frantoio’ using ‘Zhenyun’ or ‘Zhonglan’ had higher survival rate. Further experiments showed that after grafted with ‘Zhengyun’ and/or ‘Zhonglan’ as rootstocks, the scion height, leaf size and internodal length were lower, especially grafting combination with ‘Zhonglan’ as rootstock. ‘Frantoio selezione’/‘Zhonglan’, ‘Arbequina’/‘Zhonglan’ and ‘Nichiskii Ⅰ’/‘Zhonglan’ had reduced stomatal conductance and transpiration rate, and increased water use efficiency.