How to effectively prevent and control chicken-claw disease in Huangguan pears

Huangguan pear chicken-claw disease, also known as “fruit surface brown spot” or “fruit surface mottling”, generally occurs in July and August when the fruit is near maturity. Irregular brown patterns appear on the fruit surface, shaped like chicken claws, seriously affecting the appearance quality of the fruit and causing great losses to fruit growers. So what should be done when Huangguan pears get chicken-claw disease? How can it be prevented and controlled effectively?

First, let us look at the causes of Huangguan pears developing chicken-claw disease:

1. Lack of trace elements. During the formation of fruit epidermal cells, the demand for the three elements boron, zinc and calcium is the greatest, and these elements are precisely the ones most lacking in the soil of this region. The soil supply is far from meeting the needs of the tree and fruit, resulting in “chicken-claw disease”.

2. Low organic matter content. Heavy application of chemical fertilizers while neglecting bacterial fertilizers and farmyard manure reduces soil organic matter and beneficial microbial communities, causing soil compaction and low fertilizer use efficiency.

3. The influence of adverse climate. Low temperature, cloudy days, insufficient light and other climatic conditions during the fruit enlargement period are triggers for the occurrence of “chicken-claw disease”.

4. Other factors. Poor pollination, poor permeability of fruit bags, fruit bags containing toxic substances and other reasons can also easily cause “chicken-claw disease”.

Now that we have found the causes, let us look at the prevention and control measures.

Chicken-claw disease can only be prevented comprehensively; once it appears, no method will have a very good effect. The comprehensive prevention measures are as follows:

1. Supplement zinc, boron, calcium, iron and other nutrient elements.

It can be mixed in with autumn fertilization: 200 g per mu of Youli boron-zinc fertilizer produced by the US Borax group, plus 3-5 g per tree of Ruilu produced by the Swiss Ciba company; spray twice with Ciba Ruipei boron 1500 times solution 2-3 days before flowering and at full bloom; spray twice with Antaisheng 800 times after flower drop and before bagging; and spray with Ruipei calcium 2000-3000 times solution before bagging and one month before picking. This can effectively supplement the boron, zinc, calcium and other elements urgently needed for fruit growth and prevent the occurrence of “chicken-claw disease”.

2. Apply Jiayuan Yiwei microbial inoculant to increase the number of beneficial microbes in the soil, improve fertilizer use efficiency, and enhance water and fertilizer retention capacity.

Apply 500 g per mu during autumn fertilization and the fruit enlargement period, combined with two sprays of Yiwei microbial inoculant 2000 times during the growing season; this can prevent and control various diseases and play a role in promoting yield and improving quality.

3. Do a good job of pollination.

Appropriately delay the bagging time to promote peel development and aging, and enhance the peel's ability to adapt to adverse environments. When choosing pear bags, use fruit bags with good ventilation.