Naphthaleneacetic acid is best known for its excellent ripening effect. It’s no secret that many farmers and fruit and vegetable vendors have used it.
Because fruit is often not fully ripe when picked, ripening is essential to ensure a product that is marketable. Harvesting before it’s fully ripe is primarily for easier transportation. For example, fully ripe bananas are simply unsuitable for transport. Ripening with naphthaleneacetic acid is just one of its benefits, which we’ll discuss later.
What is naphthaleneacetic acid?
Naphthaleneacetic acid also has a specific definition. It is a broad-spectrum, low-toxic plant growth regulator belonging to the auxin family, meaning it promotes growth. It’s a type of plant growth promoter, similar in function to brassinolide, gibberellic acid, and forchlorfenuron.
Naphthaleneacetic acid’s mechanism of action: It is also applied by spraying on plant leaves and stems. The naphthaleneacetic acid then enters the plant’s body through these areas, including the leaves, stems, and seeds, promoting growth. However, its use differs from other plant growth regulators, with its effects varying depending on its concentration. First, high-concentration naphthaleneacetic acid solutions primarily accelerate ripening. At high concentrations, they can trigger ethylene formation, acting as a ripening agent. Second, at low concentrations, they promote cell expansion and division, prevent fruit drop, increase fruit set, and alter the ratio of male and female flowers.
Which crops are suitable for naphthaleneacetic acid?
In agricultural production, naphthaleneacetic acid is commonly used on crops such as apples, cucumbers, grapes, peaches, strawberries, watermelons, pineapples, tomatoes, wheat, and cotton. Leafy green vegetables rarely use it. Below, I’ll briefly share some practical uses and the planting problems it solves, hoping to provide a new understanding of naphthaleneacetic acid.
How is naphthaleneacetic acid used, and what planting problems does it solve?
Function 1: Promoting the production of more female flowers in a row
For example, during the cucumber seedling stage, three true leaves are considered sufficient. During this period, spraying with a 10 ml/L naphthaleneacetic acid solution once or twice will increase the number of female cucumber flowers, thereby increasing cucumber yield.
Function 2: Preventing Flower and Fruit Drop
Take greenhouse tomato cultivation as an example. Due to the high temperature and humidity inherent in greenhouse cultivation during winter, flower and fruit drop are common. To reduce flower and fruit drop, dipping flowers with a 20 mg/L naphthaleneacetic acid solution during the flowering period can prevent this problem and produce seedless fruit.
Function 3: Promoting Seed Germination
Take wheat seeds as an example. Before sowing, soaking wheat seeds in a naphthaleneacetic acid solution can increase germination rates, promote robust growth, and significantly improve cold tolerance. This involves the concentration of the naphthaleneacetic acid solution used for soaking the seeds. A naphthaleneacetic acid concentration of 20-60 mg/L is sufficient, and the soaking time should be approximately 5-8 hours. After soaking, allow the seeds to dry before sowing.
Precautions for using naphthaleneacetic acid
Key Point 1: Naphthaleneacetic acid is difficult to dissolve in cold water. It is generally best to dissolve it in a small amount of alcohol first, then dilute it with an appropriate amount of water.
Key Point 2: Naphthaleneacetic acid can be mixed with most non-alkaline substances.
Key Point 3: The dilution concentration of naphthaleneacetic acid must be strictly followed according to the instructions. Do not dilute it at will. Increased concentrations are particularly prone to phytotoxicity.
In summary: The primary purpose of using naphthaleneacetic acid is to achieve optimal yield and quality, and this requires strict adherence to the instructions. Never adjust the concentration without authorization, as this can lead to decreased yield and quality. Although it has low toxicity, excessive use is not recommended. It should be used away from farms, and protective measures must be taken when spraying naphthaleneacetic acid solutions to avoid irritation to the skin and mucous membranes.
