Flower Rot Disease On Longan And Lychee 23/08/2021

Ph.D. Nguyen Minh Tuyen

Longan, lychee is one of the agricultural crops with high economic value. However, in the production process, there are many types of pests that significantly affect the yield, quality of longan and lychee. One of the dangerous pests that often appear in the season of longan and lychee while growing flower buds and young fruits are flower bud rot disease

* Symptoms and harms:

The disease damages the longan ,lychee are budding and flowering. The disease causes flower buds, or bunch of flower buds to turn brown, then gradually turn black, then rot, dry and fall off, seriously affecting the yield of longan and lychee. The disease also often attacks on young parts such as leaves, branches and young fruits. The disease also slows down the growth of longan and lychee gardens at the basic construction stage, if not prevented in time.

 

* Harmful agents and growing conditions:

Flower bud rot is caused by the Colletotrichum sp fungus. The disease damages longan and lychee trees from the basic construction garden to the business garden. The disease often causes severe damage in the longan, lychee stage begins to produce buds, flower buds and young fruits, especially when the environment is cool, humid, drizzly and foggy.

* A number of preventive measures have been applied with high efficiency:

- Prune and clean the gardens of longan and lychee before the crop to keep the garden well ventilated, light enough and reduce humidity.

- Balanced and reasonable fertilization. Pay attention to increase the amount of potassium fertilizer. Use fertilizer TANO-601 to provide necessary microelements to increase plant resistance, increase yield and quality, as well as beautify fruit designs.

- Visit the garden regularly during the period of buds, flower buds and young fruits to make appropriate and timely prevention decisions.

- Through the people is many years of experience in preventing dry rot, it is necessary to pay attention to preventive spraying at the right time, especially in the gardens with high risk of infection, or the gardens of longan and lychee that were seriously infected in the previous year, easily leave many disease remnants on the tree. Carry out preventive spraying during  longan, lychee  at budding, flowering and young fruiting. When the garden just gets diseased, spray 2-3 times / wave, each time is about 5-7 days apart. The effective and popular product that farmers often use today is HAT VANG 250SC, or CLEARNER 75WP, or PYLACOL 700WP.

- When spraying product for longan and lychee, it is necessary to use a sufficient amount of spray water and to have a spray device to finely spray to the top of the tree to be effective.

- Mobilize surrounding gardens to prevent diseases to reduce disease sources and avoid spreading one another.

 

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