Citrus Greening is one of the most serious citrus plant diseases in the world. It is also known as Huanglongbing (HLB) or yellow dragon disease and is without a cure.A recent study carried out on the Lisbon lemon and Washington Navel orange trees to check the effects of the HLB disease . This study focussed on the root systems of these two citrus varieties using a combined metabolomics and microbiome approach. The study revealed when plants were exposed to HLB, they reduce their root sugars and amino acid intake. Moreover, the concentration of malic acid and quinic acid which are responsible for immunization differs in navel roots and lemon roots. Scientists believe that more research needs to be carried out on the different responses to HLB which may help to develop variety-specific precautionary measures.