How to prevent and control grape berry cracking? A detailed guide to practical methods
Grape berry cracking is a real headache. It often affects the market value of the grapes and makes them prone to pests and diseases. A single cracked berry can cause the whole bunch to become infected, leading to huge losses. So how should grape berry cracking be prevented and controlled? Here is a detailed guide to the prevention and control methods for grape berry cracking. Let's take a look.
1. Variety selection
A large part of the cause of grape berry cracking comes from the variety. Each variety differs in how soft the flesh is, how thick or thin the skin is, and how tightly the skin and flesh are joined, and all of these are causes of berry cracking. When selecting varieties, choose according to the local climate and soil conditions. It is best to choose varieties that are not prone to cracking, such as Jingya and Kyoho.
2. Field management
Loose, fertile sandy loam with good drainage and good permeability is the most suitable. During the grape growing period, strengthen water and fertilizer management and keep soil moisture stable. Long periods of drought or long periods of waterlogging are not advisable, and neither is irrigating heavily after a drought, as these all affect the grape's ability to regulate water. Apply fertilizer rationally to provide the nutrients the plant needs to grow. When fertilizing, follow the principle of giving priority to base fertilizer and supplementing with topdressing. Base fertilizer should mainly be organic fertilizer, matched with an appropriate amount of compound fertilizer; topdressing should mainly use nitrogen, phosphorus and potassium fertilizers plus trace elements such as calcium and boron. Especially in the later stage, topdress with boron and calcium, which can reduce the occurrence of berry cracking.
3. Rational pruning
Prune rationally and pay attention to the ratio of fruit to leaves to prevent excessive pruning, which leaves too few leaves, reduces the plant's ability to synthesize nutrients and regulate water, and leads to berry cracking later on. Generally, each fruit cluster should be left with 1-2 leaves, while shoots grown for growth should retain more than 25 leaves to strengthen the plant's water regulation capacity. In addition, proper thinning of clusters and berries can make the grapes grow robustly and avoid berry cracking caused by too much fruit and insufficient nutrient supply from the plant, or by fruit growing too densely and being squeezed into cracking.
4. Rain-shelter cultivation
When planting, it is best to set up a shed for cultivation. This not only gives the vines a support point to grow on, but also provides shelter from rain and prevents berry cracking caused by pests and diseases triggered by the rainy season. For example, building a small shed over the grape trellis or laying plastic film on the ground has an excellent effect on preventing berry cracking.
5. Scientific use of chemicals
Most growers use various chemicals to prevent and control pests and diseases, speed up swelling and promote early ripening, and these chemicals can stimulate the grapes and make them prone to cracking later on. Therefore, chemicals should be used scientifically and rationally. When preventing and controlling pests and diseases, try to focus on prevention to reduce the possibility of outbreaks. When using swelling agents, use fruit-swelling agents produced by legitimate manufacturers and follow the instructions. For ripening, ethephon is generally used, and the concentration must be watched: a low concentration gives no obvious effect, while a high concentration can cause side effects such as berry cracking and leaf and fruit drop
. In response to this situation, spraying rare earth elements during the grape swelling and coloring stages can prevent berry cracking and fruit drop.
The above is the full content of the prevention and control methods for grape berry cracking. We hope it helps you. To learn more about grape growing, please stay tuned to us.