When the weather is cold, people will wear more clothes to resist the cold. The same is true of fruit trees. It is also necessary to prevent freezing when it is cold. However, the anti-freezing of fruit trees is not as simple as putting on clothes, and it is necessary to start from the roots to improve their anti-stress ability in order to reduce the freezing injury of fruit trees, especially young trees.

Increasing the stress resistance of navel orange saplings mainly starts with plant growth regulators. Plant growth regulators can directly and effectively supplement tree nutrients and change endogenous hormone levels, thus enhancing plant vitality.

Here are some common plant growth regulators.

I. Paclobutrazol

The main function of paclobutrazol is to inhibit the synthesis of gibberellin in plants, slow down the growth rate of plants, promote the differentiation of tillers and flower buds, increase the stress resistance of plants and increase the yield.

In addition, paclobutrazol can also alleviate water loss and enhance the drought resistance of plants.

Navel orange with paclobutrazol will have darker leaves, higher photosynthetic pigment content, higher nucleic acid content and higher protein content, thus making the plant more vigorous.

When paclobutrazol is used in navel orange, the content of abscisic acid, a stress hormone, will be increased in plants, thus reducing the damage of low temperature environment to leaf cell membrane, which is the antifreeze principle of paclobutrazol.

Second, brassin.

Brassica is an efficient, broad-spectrum and non-toxic plant growth regulator, which can effectively increase chlorophyll content, protect flowers and fruits, increase yield and improve crops' cold resistance and drought resistance. It can be said that he is an all-round plant protection expert.

Brassica can enlarge fruit by dividing plant cells. Promoting lateral bud germination, increasing flower quantity and improving pollen pregnancy rate can improve yield.

Three. monopotassium phosphate

Potassium dihydrogen phosphate is called universal fertilizer, which can not only promote flowering and fruiting, but also increase leaf thickness, enhance plant photosynthesis, increase fruit setting rate and improve fruit quality.

Rapeseed and potassium dihydrogen phosphate used together can effectively prevent frostbite, which is "prevention". If frostbite has been caused, spraying it again will have no effect.

Potassium dihydrogen phosphate can decompose phosphorus and potassium in soil and improve the absorption and utilization rate of phosphorus and potassium.

These are the three most commonly used plant growth regulators for citrus fruit trees, and you can use them reasonably according to the actual situation.

If the tree is too strong, paclobutrazol can be used to inhibit growth; Brassica and potassium dihydrogen phosphate can be used to prevent freezing and promote flower bud differentiation of young trees; Brassica can be used to protect flowers and fruits and increase yield; Potassium dihydrogen phosphate can be used to improve quality.

In short, before we use the product, we should have a general understanding of its functions in order to make the best use of it.