In the practice of agricultural production, we often encounter situations where fruit trees bear too much or too little fruit.
When the fruit trees bear too little fruit, we must take effective measures to effectively "protect the fruit" of the fruit trees, so as to ensure the abundant and stable yield of the fruit trees and obtain the maximum planting benefits. When the fruit trees bear too much fruit, we should effectively "thinn the fruit" of the fruit trees to ensure the "upgrading" and sustainable development of the fruit quality.
Picture 01~02): Plum high-quality fruit
As one of the common fruit trees, when the amount of fruit exceeds the carrying capacity of the tree, it will not only affect the quality of the fruit, but also may cause the tree to weaken, and even affect the yield of the following year. Therefore, proper fruit thinning is an indispensable part of plum tree cultivation and management.
In this issue of pictures and texts, Qingjiang Crane will focus on and chat with all the teachers about how to carry out chemical fruit thinning when the fruit tree "plum" bears too much fruit, aiming to discuss how to choose ethephon, paclobutrazol, naphthalene acetic acid and stone sulfur mixture for chemical fruit thinning to replace artificial fruit thinning when the plum tree bears too much fruit, and when to use these agents "chemical fruit thinning" The effect is better, and points out the problems that need to be paid attention to in the operation process. I hope you like and actively participate in the interaction, forward and share the pictures and texts of this issue.
Picture 03~04): The rate of high-quality fruit increases after chemical fruit thinning
Application of plant conditioner ethephon in chemical fruit thinning of plum trees:
As a plant growth regulator, ethephon can regulate the physiological processes of fruit trees and can effectively promote fruit ripening and coloration. In the case of excessive fruiting of plum trees, the appropriate use of ethephon can effectively reduce the number of fruit sets and improve the quality of the remaining fruits.
The use of ethephon is usually before the rapid expansion of the fruit (generally within 15~18 days after plum flowering), when the fruit has not been completely set, and the burden on the tree body is less after fruit thinning, and it is also conducive to improving the size and color of the fruit.
Picture 05~06): Effect of chemical fruit thinning
For example, after two-thirds of the plum blossoms, spraying plums with ethephon 200ml/L within 2 to 3 weeks can achieve the purpose of effective chemical fruit thinning, but has no adverse effect on plum trees.
However, the main ethephon agent sold in the agricultural materials market is 40% ethephon liquid, and the concentration can be determined according to the actual situation.
Promoting effect of phyto-adjusting agent paclobutrazol on chemical fruit thinning of plum trees:
Paclobutrazol is a triazole plant growth regulator that has the effect of inhibiting the growth of fruit trees, so that more nutrients are distributed to fruits by reducing the extraction of new shoots and the expansion of leaves.
Picture 07~08): Ethephon can thin the fruit
In the year when the plum tree bears too much fruit, the use of paclobutrazol can effectively control the tree momentum and reduce the growth of ineffective branches and leaves, so as to indirectly achieve the purpose of fruit thinning.
The best time to use paclobutrazol is usually before the fruit hard core stage (June), when the nutrient requirements of the tree are relatively low and the effect of the agent is more obvious.
The whole plant can be sprayed with paclobutrazol 1000~2000mg/L solution, which can play a good role in "thinning fruits", so that the volume and weight of fruit-setting plums increase.
The paclobutrazol sold in the agricultural market mainly includes 10% paclobutrazol wettable powder, 15% paclobutrazol wettable powder, and 25% paclobutrazol suspension. Due to the different dosage forms and contents, the concentration should be used according to the recommended standard of the outer packaging bag, and the concentration should not be increased or decreased without authorization.
Picture 09~10): Chemical fruit thinning can be carried out with stone sulfur mixture
Application skills of plant conditioning agent naphthalene acetic acid in chemical fruit thinning of plum trees:
Naphthalene acetic acid, as a "flower and fruit thinning agent" in fruit trees, can promote fruit shedding, but its effect is relatively mild, and does not cause fruit shedding as quickly as ethephon.
Therefore, when the plum tree bears too much fruit, the use of naphthalene acetic acid can gradually reduce the number of fruit sets without damaging the tree body, so as to reduce the load of the fruit tree, improve the quality of the branches and fruits, upgrade the file, and increase the added value of the commodity.
The use time of naphthalene acetic acid is generally selected in the fruit expansion period or full flowering period (to achieve the purpose of fruit thinning by thinning flowers), at this time, the sensitivity of the fruit to the agent is moderate, which can not only achieve the effect of fruit thinning, but also will not have much impact on the quality of the fruit.
Picture 11~12): Chemical fruit thinning can be performed with naphthalene acetic acid
In the full flowering period of plum, the flowers and plants of plum can be sprayed with naphthalene acetic acid 20mg/L~30mg/L, which can effectively thin the flowers, so as to achieve chemical fruit thinning.
At present, the naphthalene acetic acid sold in the agricultural market has a variety of naphthalene acetic acid with different content and dosage forms, pay attention to the difference and choose the appropriate naphthalene acetic acid according to their own production needs.
The main varieties of naphthalene acetic acid are 0.03% naphthalene acetic acid aqueous solution, 0.1% naphthalene acetic acid aqueous solution, 0.6% naphthalene acetic acid aqueous solution, 1% and 5% naphthalene acetic acid aqueous acid, and 20% naphthalene acetic acid wettable powder and 90% naphthalene acetic acid powder.
The auxiliary role of fungicides, insecticides, stone sulfur mixtures in chemical fruit thinning on plum trees:
As a broad-spectrum fungicide, insecticide, and acaricide, stone sulfur mixture plays an important role in the control of fruit tree diseases and pests.
Picture 13~14): Stone sulfur mixture and paclobutrazol
In the case of too much fruit of plum trees, the use of stone sulfur mixture can also effectively control the occurrence of pests and diseases, reduce fruit shedding and quality degradation caused by pests and diseases, and can also chemically thin the fruit.
At the same time, the use of stone sulfur mixture can also enhance the resistance of the tree and create favorable conditions for subsequent fruit thinning work.
Practice has proved that spraying 0.3~0.4 Baumé stone sulfur mixture solution in the full flowering period (1~2 days) of "Flavor Queen", "Dinosaur Egg", "Flavor Emperor", "Apricot Plum", "Victoria Plum" and "Ou Plum" can effectively "thin flowers" to achieve the purpose of "fruit thinning". It can also effectively increase the soluble solids content, sugar content, and acid content of the fruit. Improve the appearance of fruits, increase the added value of commodities and planting benefits.
Picture 15~16): The rate of high-quality fruit increases after chemical fruit thinning
Precautions for chemical fruit thinning with plant agents, insecticides, fungicides:
When thinning plum fruit with plant conditioners ethephon, paclobutrazole, naphthalene acetic acid and insecticides, fungicides, acaricides, and stone sulfur mixtures, the following points need to be noted:
First of all, it is necessary to strictly control the concentration and dosage of pesticides to avoid excessive use of damage to the tree (pesticide damage).
Secondly, it is necessary to choose the appropriate agent and use time according to the growth status of the tree and the development stage of the fruit (so that the effect of the agent reaches the extreme).
Finally, it is necessary to follow the safety regulations for the use of pesticides to protect the environment and human health. Ensure that pesticide residues have no negative impact on people, animals and the environment.
Picture 17~18): High-quality and high-yield cultivation of fruit trees
Words written at the end:
In summary, when plum trees bear too much fruit, the rational use of ethephon, paclobutrazol, naphthalene acetic acid and stone sulfur mixture and other agents for fruit thinning can effectively control the number of fruits, improve fruit quality, and lay a solid foundation for the healthy growth and efficient production of fruit trees. In actual operation, it is necessary to pay attention to the use of the agent and precautions to ensure the smooth progress of fruit thinning.
Picture 19~20): Plums in the field in a stable yield