In the mid2000s, Brazil has reported the disease citrus greening or huanglongbing (HLB), considered one of the most destructive diseases in plants by its complexity. As an agent associated with HLB, we have bacteria: "Candidatus Liberibacter americanus", "Ca. Liberibacter asiaticus "," Ca. Liberibacter africanus". Symptoms of greening may be masked by other symptoms generated from some diseases, besides such symptoms are similar to those caused by various mineral deficiencies. The objective of this study was to verify if the HLB affects the accumulation of nutrients in citrus flowers. The experiment was in Valencia oranges trees (C. sinensis) on Rangpur lime (C. limonia) with 12 years of age. Treatments consisted of: 1) symptomatic branches of flowers (PCR+), 2) asymptomatic branches of flowers (PCR+) and 3) flowers of healthy plants (PCR-). The levels of macronutrients and micronutrients were measured  in December of 2011. The results showed lower levels of N, P, K, Ca, Mg, B, Fe, Mn in the flowers of diseased plants (asymptomatic and symptomatic) compared with the levels of certain nutrients in healthy plants. The reduction in nutrient concentration mobile (N, P and K) as not mobile in the phloem (Ca and B) shows that the absorption and distribution of nutrients were reduced in young tissues and justifies the diversity of symptoms found. The nutrients are involved in the activation / inactivation of enzymes related to metabolism and biosynthesis of plant hormone, auxin, gibberellins and cytokinins, which regulate the abortion of plant organs.

Plants infected with HLB have obstructions that affect the phloem transport of carbohydrates for developing organs such as fruit and other organs as the cambial region and roots. Some nutrients may be affected and it is usual the observation of foliar symptoms characteristic for the deficiency of minerals such as Mg and Zn. As the root system can also be harmed it is possible that the deficiency symptoms are also caused by decreased absorption and not only by lack of redistribution through phloem. The objective of this study was to investigate throughout the year concentrations of different nutrients in young leaves, mature leaves, young branches and the cambial region of Valencia Orange trees (C.sinensis), 12 years old, grafted on Rangpur lime (Citrus limonia) . 1) symptomatic branches of flowers (PCR+), 2) asymptomatic branches of flowers (PCR+) and 3) flowers of healthy plants (PCR -). Healthy plants showed higher levels of nitrogen, calcium, magnesium, zinc and copper. There were variations in function of the analyzed organs over time. The results are discussed according to the mobility of nutrients in plants.