Citrus scion/rootstock combinations show tolerance to huanglongbing

The citrus disease huanglongbing (HLB) is endemic in Florida, where it is estimated that more than 80% of citrus trees are currently infected. Largely as a result of this devastating disease, Florida citrus production in 2014-15 was the lowest recorded in the past 50 years. Sweet orange and grapefruit, which account for more than 95% of Florida citrus production, appear to be especially compromised by HLB. Understandably, there is an urgent need to identify citrus varieties that can resist the w