How to prevent and control grape sunburn? These measures you need to master

Grape sunburn is a physiological disease that mainly occurs during the young berry expansion stage, which is exactly the period of high temperature and strong light. When the grape clusters lack shade, strong light radiation mainly causes dehydration and sunburn on the berry skin. So how should grape sunburn be prevented and controlled? Let's take a look at the introduction of prevention and control measures.

1. Damage symptoms

It mainly occurs on the clusters. After being damaged, light brown patches appear on the surface of the berries, gradually spreading into sunken dry scars, and stop occurring before the fruit ripens. Sunburn generally occurs in the young berry stage and the berry expansion stage. At first, the berries show dehydration, sunken areas, and light brown patches. As the condition worsens, the lesions gradually expand until the surface tissue of the fruit dehydrates and the lesions dry up.

2. Causes

During periods of high temperature and strong light, clusters lacking shade from leaves will cause dehydration and sunburn on the parts of the fruit exposed to light, or it is caused by leaves and fruit competing for water. Poor vine vigor in grape plantings, poor root growth, small and few leaves, and uneven fertilization can also cause grape sunburn. In addition, the occurrence of sunburn is also closely related to the grape trellis system, vine vigor, cluster orientation and fruit load, and the timing of fruit bagging and the quality management of fruit bags. Clusters growing on the sunny side suffer more severe sunburn, late bagging also aggravates sunburn, and excessive fruit set also aggravates sunburn.

3. Prevention and control measures

Choose a reasonable planting density and adopt a trellis system so that the clusters grow in shaded places and avoid direct exposure to strong light. Apply appropriate topdressing during the growing period to strengthen vine vigor and improve the stress resistance of grape plants. During the rainy season, do a good job of drainage and humidity reduction to avoid waterlogging and root rot. Pay attention when fertilizing to avoid excessive fertilization or overly concentrated fertilizer causing root burn in grape plants. In high temperature weather, you can increase watering and spraying to lower the plant temperature. At the same time, you can also spray Guotiling plus Xin Gaozhi film to improve grape coloration and avoid sunburn. The timing of bagging must be appropriate to reduce sunburn damage to the fruit from strong light. In addition, the choice of bags must be waterproof, white, and highly breathable.

The above is an introduction to the prevention and control measures for grape sunburn. I hope it can help you. To learn more related knowledge, please stay tuned to us.