T20 Kills 99% of Aphids on a Peach Orchard
June 25, 2021
AGRAS T16
A peach orchard in Jingshen Village, Taigu District, Shanxi province suffered devastating aphid swarms this year due to insufficient pest control and unfavorable weather, which would have resulted in severe yield decreases if not controlled. The DJI Agriculture T20 aerial application drones were used to spray pesticides to control the pests in the orchard.
This operation was carried out in Jingshen Village, Taigu District, Shanxi province on June 3, 2020. The peach trees were 10-15 years old and 2 meters high with a crown diameter of 3 meters, and in the shape of open-top heart.
Overview of Pests
A large number of aphids were found on leaves, trunks and branches of the peach-bearing trees, particularly on the tender treetops, with up to 800-1,000 aphids on the back of a single leaf. As a result, the leaves curled, withered and turned black.
Aphids cause severe damage
Operation Parameters
Interpretation of Parameters
Speed (2m/s): Given the severe damage caused by the aphids, the operation speed was set to 2m/s to ensure a sufficient dosage was kept for the back of leaves.
Operation spacing (4m): The peach trees are in the shape of an open-top heart, with thin crowns, and a width of up to 4m.
Water consumption per hectare (75L): Water consumption was increased to 75L/hectare given the massive number of aphids on the backs of leaves.
Flight height (2m): Testing data indicated that 2m was high enough for the spray to penetrate the crown canopy, given the large weight of T20 and the strong wind.
T20 in operation
Pesticide Information
Note: The pesticide consumption was increased as a result of the severe damage caused by aphids resulting from poor management. Besides, proper adjustments are needed depending on the severity of the damage caused by the pests and the density of the crown canopies. Other pesticides may be used as alternatives in the future to avoid pesticide resistance with the aphids.
Pesticides
In this case, acetamiprid and avermectins-imidacloprid were used.
1. Acetamiprid
This product is a nitromethylene heterocyclic pesticide, which kills pests on contact and causes stomach poisoning. The pesticide is highly penetrative and can effectively control aphids and other pests. It targets the nicotinic acetylcholine receptor at the synapse of the insect’s nervous system to interfere with the conduction of stimulus and blocks the pathway of the nervous system, resulting in a buildup of acetylcholine at the synapse, and paralyzing and eventually killing the insects.
The product is toxic to bees and silkworms and should be handled with caution during florescence. Do not use it together with any alkali substances.
2. Avermectins-imidacloprid
This product is a compound of avermectins and imidacloprid.
(1) Avermectins
The product is a macrolide disaccharide pesticide, which kills pests on contact and causes stomach poisoning and has slight fumigation effect. It kills imagos but not eggs. It interferes with the insect’s nervous physiological activities.
The product is toxic to bees and silkworms and should be used with caution during florescence. Do not use it together with any alkali substances.
(2) Imidacloprid
The product is a nitromethylene pesticide, which kills pests on contact and causes stomach poisoning as well as systemic effects. It can control aphids effectively. Upon reception of this pesticide, the normal conduction of the central nervous system of the pest is blocked, resulting the paralysis and death.
The product is toxic to bees and silkworms and should be used with caution during florescence. Do not use it together with any alkali substances.
Control effect
Follow-up 72 hours after application: Evaluation conditions: under normal weather conditions, without rain, and within 72 hours after application. According to the on-site evaluation by the Plant Protective Station of the Agriculture Bureau of Taigu District, Jinzhong City, Shanxi Province, the control effects are as follows:
For treetops with severe insect damage, the death rate of aphids on the front of leaves was greater than 99%, while on the back of leaves greater than 95%, and on the trunk greater than 99%. The results met expectations.
Effect after application
Aphids on treetops with minor pest damage were essentially eliminated, and the health of leaves was obviously improved.
More than 95% of the aphids on the surface of bearing leaves were killed.
All aphids on the trunks were eliminated.
Summary of Experience
(1) The aerial application drones used for this operation are suitable for peach trees. The pesticide was properly selected, and the dosage met the requirements given the pest damage. The flight parameters and the flight plan were appropriate. In addition, the meteorological conditions were also satisfactory. Therefore, the pest control was very successful.
(2) Wind scale: During this operation, the wind scale was 0, which had no impact on spraying. In case of stronger wind, it is advised to lower the flight height as needed. When the wind exceeds gentle breeze, stop spraying.
(3) The temperature (30°C) and the relative humidity (80%) had little impact on the deposition and evaporation of the mist. In case of high temperature or low relative humidity, increase the water amount as needed, or stop spraying.
(4) Flight parameters: With a broad wind field, the T20 drone covered the whole crown canopy. It is suggested that various speeds and operation spacings should be tested in the future to ensure higher efficiency of T20 for operation on peach trees.
About Our Team
This pesticide application effect test is a field test for the project “Standard Operation Code for Plant Protection Machinery in Orchards”, which is jointly implemented by DJI Agriculture and the Center for Chemicals Application of China Agricultural University.
The test was supervised by Professor Wu Zhiming from Shanxi Agricultural University. A group of experts determined the flight parameters, plan, and pesticide technology. No repeated spray and missing spray were found during the field operation, and the pesticides were evenly applied, indicating that the Fruit Tree mode of T20 drones has satisfactory effect.