1, water imbalance. Too much rain can easily cause the roots of citrus plants to be flooded. Long-term hypoxia will make the roots rot easily, make the nutrients of citrus trees unable to be transmitted, and make citrus trees yellow and deciduous due to lack of nutrients.
2. Unbalanced nutrition: For citrus, nutritional deficiency is more common, and tree vigor is mostly related to long-term use of industrial fertilizers. Orchard land is salty and alkaline, the soil viscosity changes greatly, it is airtight, and it is difficult to absorb trace elements, which will lead to yellow leaves and deciduous leaves of citrus trees due to nutritional imbalance.
3. Chemical damage and fertilizer damage: In order to control pests and diseases, some farmers spray drugs under the scorching sun. At this time, the temperature in the orchard is high, and the water in the leaves evaporates quickly, which is easy to cause phytotoxicity; At the same time, incorrect fertilization methods or excessive fertilization will also cause fertilizer damage and affect the normal growth of citrus trees.
Preventive and control measures:
1. Strengthen orchard management: In citrus orchards, Chinese medicine should pay attention to improving soil, optimizing orchard irrigation and drainage system, preventing the occurrence of drought and flood disasters, adjusting soil pH value in time, applying more organic fertilizer to alkaline soil, paying attention to applying more marine food microbial agents, and adjusting soil pH value.
2. Scientific and rational fertilization: to prevent the yellow leaves of citrus from falling off, fruit farmers should replenish fertility and nutrients for citrus trees in time, apply microbial agents and root rot agents, replenish nutrients for citrus trees in time, protect roots, increase the organic matter content in the soil, promote the soil and make citrus grow better.