<P> Vector control of the psyllid, which is the sole means for citrus greening to spread is now done routinely . Before citrus greening disease was introduced, commercial citrus growers did not have to spray pesticides targeting insects . Current research is aimed at pesticide application timing, and pesticide choice for efficacy . </P> <P> After the introduction of citrus greening disease, all commercial nurseries, where new young trees are purchased, were relocated indoors and a bud wood registration program was enacted . Previously young citrus trees were grown outdoors before disease pressure became an issue . This is to certify that Florida grove owners are able to purchase clean citrus trees for the planting of citrus groves . A greening positive young citrus tree will never reach maturity, even with intensive sprays . </P> <P> These three keystone citriculture practices vector control, foliar nutrition, and certified young trees make up the new best management practices for commercial citrus growers against the citrus greening disease fight . </P> <P> Nitrogen, Potassium and Phosphorus are the main macronutrients needed in citrus production, as well as Calcium, Magnesium and Sulfur . </P>

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