What is the small black insect inside the chrysanthemum
As a traditional famous flower in China, chrysanthemum often suffers from pest problems in courtyard cultivation and potted plant care. The dense small black spots that suddenly appear on the back of the leaves are actually the amazing繁殖力 of chrysanthemum aphid pests. These hemipteran pests hinder plant growth by刺吸汁液, and in severe cases, cause flower buds to deform and fall off. This article will systematically analyze the causes of pest damage and provide four scientific control solutions.
Chrysanthemum Aphid Characteristics and Harm Manifestations
Insect Morphology Identification
The adult chrysanthemum aphid is 1.5-2mm long, black-brown with luster, and聚集寄生 on tender shoots and sepals. The nymphs are yellow-green and can produce more than 80 offspring per female through thevirgin birth in just 7 days.
Symptom Judgment of Harm
Infested plants show symptoms such as curled leaves, honeydew contamination, and sootyc霉病 coinfection.侵害 during the flower bud stage can lead to a drop in flowering rate of over 60%, and intervention is required when the insect density reaches 5 heads/leaf.
Detailed Explanation of Four Chrysanthemum Aphid Control Solutions
Chemical Control Method
Use 10% imidacloprid wettable powder 1500 times liquid or 25% thiamethoxam water-dispersible granule 3000 times liquid, focusing on spraying the back of the leaves. Biological pesticides can include 1.5% pyrethrin aqueous emulsion, with a continuous application interval of 7-10 days.
Physical Fumigation Method
Hang electric mosquito repellent patches above the plants and cover them with a transparent plastic bag for 2 hours. Be cautious to avoid operating during the high-temperature noon hours and ventilate promptly after fumigation.
Plant-derived Control
Prepare an emulsion by diluting eucalyptus oil 1:400 with water and adding 0.1% neutral soap to enhance adhesion. Orange peel extract (fresh orange peel: water = 1:5 soaked for 24 hours) can damage the waxy layer of aphids.
Environmental Regulation Method
Keep a plant spacing of more than 30cm and regularly prune dense branches. Use drip irrigation technology to avoid leaf wetness and配合 hanging yellow sticky traps to monitor pest conditions.
Comprehensive use of physical removal and chemical control, combined with optimization of cultivation environment, can establish a long-term control mechanism for chrysanthemum aphids. It is recommended to carry out preventive spraying every early spring when the plants start to sprout and to check the back of the leaves for insect eggs daily to achieve source control of pest damage.