Some farmers have raised questions. Although their crops grow robustly, they bloom and bear fruit relatively slowly. What is the reason?
In fact, the problem of crops growing robustly but flowering and bearing fruit slowly is often due to the lack of a key signal substance in the body. This substance is vital to plants. It can promote plants to smoothly switch from vegetative growth to reproductive growth at the growth node. However, certain environmental or fertilizer and water factors may cause insufficient synthesis of this substance or delay the time.
To address this problem, we can take measures, such as artificially adding certain ingredients, to accelerate the synthesis of this signal substance. Today, I will introduce you to a plant growth regulator called phthalanillic acid. It can coordinate the balance between vegetative growth and reproductive growth, improve pollen maturity, and thus promote the healthy growth of crops.
Next, let's take a closer look at phthalanillic acid. As a plant growth regulator, phthalanillic acid has excellent systemicity. Through foliar spraying, it can quickly penetrate and transmit to the whole body of the plant, effectively regulate the transport of nutrients, and help crops transform smoothly.
Mechanism of action of Phthalanillic acid
Promote flower bud differentiation and fruit setting
Its effects are mainly reflected in the following aspects:
1. Promote flower formation: Phthalanillic acid can promote the formation of chlorophyll and anthocyanin, improve the photosynthesis efficiency of leaves, and thus accumulate more dry matter. It can also alleviate the problem of insufficient endogenous hormone secretion during the flowering period of plants, meet the demand for growth hormones for flower bud differentiation, and promote the concentration of nutrients to the growth point of flower buds.
Improve fruit quality and stress resistance
2. Preserve flowers and fruits: Phthalanillic acid can activate plant cells, ensure the normal division of ovary and dense disk cells, and at the same time, the stigma is relatively elongated, which is conducive to pollination and fertilization. This effect directly increases the fruit setting rate and reduces the shedding of young fruits.
3. Improve quality: This substance can promote further expansion of fruits, thereby increasing yields. It can also increase the content of endogenous hormones, inhibit the action of abscisic acid, reduce the separation layer between fruit stalks, effectively prevent physiological and pre-harvest fruit drop, and even advance the natural maturity period by 5 to 7 days.
4. Enhance stress resistance: Phthalanillic acid has an excellent root-promoting effect, which can help crops resist premature aging and enhance resistance to adverse climates such as low temperature, frost, drought, rain, dry hot wind, etc.
Comparison between Phthalanillic acid and gibberellin
Action characteristics and concentration differences
The action characteristics of Phthalanillic acid are similar to those of gibberellin, but there are differences between the two. In terms of concentration, the concentration of phthalanillic acid is relatively high.
Superiority under adverse conditions
When using plant growth inhibitors such as chlormequat, mepiquat, paclobutrazol, etc., these inhibitors will inhibit the biosynthesis of gibberellin, but will not affect the effect of phthalanillic acid. Especially under adverse conditions, such as drought and low temperature, phthalanillic acid is significantly better than gibberellin in promoting flowering and fruiting. In addition, in the later stages of fruit growth, it can also effectively inhibit the premature shedding of fruits, which is also better than gibberellin.
Phthalanillic acid usage techniques and precautions
Application methods for different crops
When applied to soybeans, you can choose to use 20% phthalanillic acid soluble concentrate at the bud stage, early flowering stage or after flowering, dilute it at a ratio of 300-400 times, and evenly apply it by spraying. Note that in each growth cycle of soybeans, you can only apply the medicine twice at most.
For citrus trees, it is recommended to use 20% phthalanillic acid soluble concentrate at the young fruit stage, dilute it at a ratio of 1000-1500 times and spray it. It is also necessary to ensure the uniformity and thoroughness of the application. Apply the medicine at most once per season, and the safe interval is 30 days.
For field crops, phthalanillic acid can be used in both wheat and corn at key growth stages. For wheat, the medicine can be applied once at the jointing stage and the flowering stage; while corn is suitable for application at the 5-6 leaf stage and the 10-12 leaf stage. It should be noted that the safe interval for fresh corn is 21 days, while for mature corn it is 45 days. In addition, rapeseed can also be sprayed during the bolting and early flowering stages.
For mango, it is recommended to spray once before the mango flowers and once after the flowers wither. Use 20% phthalanillic acid soluble solution and spray it with 1500-2500 times the amount of the preparation according to about 2.5-4 kg of water per plant. Avoid spraying in windy weather or when rain is expected within 1 hour.
Phthalanillic acid compounding and synergistic effect
Phthalanillic acid can be compounded with macronutrient water-soluble fertilizers and sprayed on the leaves to provide plants with essential nutrients, adjust the carbon-nitrogen ratio, and thus promote reproductive growth and increase yield. Experiments have shown that when phthalanillic acid is used in combination with hypersensitive protein, the two can produce a synergistic effect, significantly advance the flowering time (5 to 7 days), increase the number of flowers, improve the quality of flowers, thereby increasing the fruit setting rate and reducing physiological fruit drop, and ultimately increasing the yield by 20% to 30%. It should be noted that phthalanillic acid does not contain fertilizer components and cannot replace essential nutrients for plants. Therefore, after use, as the number of flowering and fruit setting increases, the supply of fertilizer and water should be increased accordingly to ensure the healthy growth of the plants.
Safe operation and precautions
When applying phthalanillic acid, spraying should be avoided under the scorching sun, and if it rains within 3 hours after application, it needs to be sprayed again. In addition, phthalanillic acid should not be directly mixed with strong acids, strong alkalis or other pesticides. Used pesticide packaging waste must not be discarded or disposed of at will, but should be returned to a special pesticide packaging waste recycling station. At the same time, it is prohibited to wash the application equipment in rivers and ponds and other water bodies, and the remaining liquid after application must not be dumped at will. Used containers should be properly handled to avoid other uses or random discarding.
