Citrus oil blotch is a physiological disease that occurs only on mature or near mature fruits. It is due to the breakage of the oleosin of the pericarp and the infiltration of the peel skin after the oil of the orange peel is invaded. Occurrence of citrus oil spot disease is mainly caused by excessive rain during fruit ripening, severe winds, or severe day and night temperatures, resulting in the rupture of some of the pericarp oleaginous cells around the fruit pedicle, or it may be caused by rain or morning dew. Dry eager to harvest, or damage the skin in the harvest and disease. The incidence of citrus oil blotch is closely related to the variety. Generally, the varieties with fine and crisp skin structure have more incidence, and the rough and loose varieties have less incidence. Because oily spot occurs only in the oil skin of the outer layer of the tree orange peel, it will not cause pulp rot in the dry conditions, but oil spot disease will seriously affect the appearance of the fruit and reduce the commercial quality, at the same time, in the lesion It is prone to other germs that cause decay and deterioration of the fruit during storage. Citrus oil spot is a kind of physiological disease. At present, there is not a targeted drug plus control, but it can only be carefully controlled in production and harvesting. The main methods are as follows: 1. Try to avoid fruit picking when the rain and morning dew do not dry or immediately after the strong winds, and pick fruit after 2-3 sunny days after the rain. 2. As far as possible during harvesting, selection, packing, transportation and storage, it should be done lightly, lightly and lightly to avoid damage to the skin. 3, before the frost harvest fruit, or in the harvest 20 days before the application of lime on the fruit can also reduce the incidence of the disease. According to some tests, the correct use of 2,4-D preservatives in the process of preserving the fruit in the preservative process also has the effect of reducing the occurrence of oil spot disease, that is, 1 pack of Mandelity+2,4-D2 to 3 packs+Clearwater 8-10. Kg, do not arbitrarily increase the concentration of 2.4-D, while 2,4-D must first use warm water or a high concentration of shochu to fully dissolve and then mix thoroughly with Wanli De and Qing Shui and then dip the fruit to reduce the occurrence of oil-spot disease. , orange farmer friends do not imitate also try.