All You Need to Know About Asian Citrus Psyllid

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Asian Citrus Psyllid, or ACP for short, is a tiny insect that poses a significant threat to the citrus industry. In this post, we'll take a closer look at what ACP is, its characteristics and impact on citrus trees, prevention and control measures, and more.

What is Asian Citrus Psyllid (ACP)?

Asian Citrus Psyllid, also known as Diaphorina citri, is an insect about 3-4 millimeters long. The bug is brown and has white circles. It is capable of transmitting the bacterium Candidatus Liberibacter asiaticus (CLas), causing the disease called Citrus Greening, which can kill citrus trees.

History of ACP and Its Spread

The Asian Citrus Psyllid is native to Southeast Asia, but it has spread globally in recent years. The pest was first discovered in Florida's Broward County in 1998 and then found in other parts of the state. Since then, ACP has spread throughout the United States and into many countries worldwide.

Why is ACP a Threat to Citrus Industry?

As previously mentioned, the primary threat posed by Asian Citrus Psyllid is the disease it spreads caused by Candidatus Liberibacter asiaticus. Greening disease results in abnormal development of leaves, roots, and fruits of citrus, reducing yield and fruit quality, before ultimately killing the tree. The devastating disease can be transmitted to healthy trees by ACP nymphs or adults feeding on foliage and citrus fruits.

Asian Citrus Psyllid Facts and Characteristics

Physical Appearance

Asian Citrus Psyllids are tiny insects, with adults measuring between 3-4 millimeters long. They are brown and have white circles on their wings. Nymphs resemble scale insects and aphids, elongated and yellow-orange in color.

Life Cycle of ACP

Asian Citrus Psyllid undergoes a process called "gradual metamorphosis," wherein the immature nymphs resemble small wingless adults. The females lay their eggs on the new growth flushes of citrus trees, with one egg laid per leaf. Eggs hatch into tiny nymphs after 3 to 14 days. After passing through five developmental stages over two to four weeks, an adult psyllid emerges.

The Impact of ACP on Citrus Trees

The Asian Citrus Psyllid has had tremendous negative effects on the citrus industry worldwide due to the spread of the Greening disease. Citrus Greening (Huanglongbing) causes yellowing and blotching of leaves, a severe loss of yield fruits, bitter fruit taste, and ultimately death within years. In addition to this, the presence of ACP and its eggs can cause cosmetic damage to the fruit that reduces the market value of produce.

Prevention and Control Measures for ACP Infestation

Best Practices in ACP Management

There are multiple best practices in ACP management, which involve regular monitoring and removing infested trees, timely pruning, and blocking pests using plant covers, repelling agents such as neem and garlic extracts or biological treatments to interrupt the life cycle of the insect. Other preventive measures include planting non-susceptible plants, observing proper sanitation practices, and careful management of irrigation and fertilizer.

Use of Pesticides to Control ACP Infestation

The use of insecticides is the most common type of control measure deployed against Asian Citrus Psyllid. Insecticides are available for field, commercial, and home use. However, their impact on environmental health should be assessed, along with the pesticide's potential effect on non-target organisms, including other beneficial insects and mammals.

The Fight against ACP Continues

Asian Citrus Psyllid continues to be an ongoing problem worldwide for the citrus industry. Although extensive research has been conducted, there is no known cure for the Greening disease caused by Candidatus Liberibacter asiaticus - thus it's essential to prevent infestations.

Importance of Citrus Industry in the Global Economy

The massive role of the citrus industry in the global economy cannot be overemphasized. For instance, citrus fruits are one of the top fruits sold globally, while citrus crops generate significant income and jobs both in developed and developing countries. Thus, the economic significance of preventing the spread of ACP and Citrus Greening globally can not be overemphasized.

FAQ

• What is Asian Citrus Psyllid, and what does it do?

  Asian Citrus Psyllid is an insect that spreads the bacterium Candidatus Liberibacter asiaticus, causing a fatal disease called Citrus Greening in citrus trees, leading to production and overall tree loss.

• Why Is Asian Citrus Psyllid a threat to citrus trees and the industry?

  The primary reason being, the itty-bitty Asian Citrus Psyllid serves as a vector for the bacteria that causes Citrus Greening disease in citrus trees, which eventually kills them within a few years of contracting the disease.

• What are the common management practices against ACP infestation?

  Regular monitoring and removing infested trees, timely pruning, blocking pests through plant covers, repelling agents such as neem and garlic extracts or biological treatments to interrupt the life cycle of the insect. Other preventive measures include planting non-susceptible plants, observing proper sanitation practices, and careful management of irrigation and fertilizer.

• Can pesticides effectively control ACP populations?

  Yes, but their impact on environmental health should be assessed, along with the pesticide's potential effect on non-target organisms. Long term use of pesticides could also lead to the development of resistance and earlier toxicological effects.

• What can farmers and gardeners do to prevent ACP infestation?

  Farmers and gardeners alike may take multiple actions to prevent ACP infestations by following proper sanitation procedures, using varieties less susceptible to the psyllids spread of the CLas bacteria infection, ensuring proper care of orchards, immediate removal of infected plants and basic pest prevention measures.

• What's being done to contain the spread of ACP and Citrus Greening?

  There are numerous ongoing efforts, including developing resistant horticultural varieties, coordinating agricultural service response to quarantine produce, encouraging regular & widespread commercial citrus applications of preventative pesticide treatments, increasing awareness campaigns about biosecurity and disease vectors, amongst other top global collaborative programs.

• What's the role of government in ACP and Citrus Greening management?

  Governments worldwide have active collaborations with research communities and local stakeholders in managing Asian Citrus Psyllid; oversight inspections and quarantine regulations protect trade from further spreading Greening Disease.

• How does ACP affect the global economy?

  The woeful impact caused by the spread of disease on the citrus industry and the economy cannot be underestimated. Pest control measures drive up costs in affected regions, leading to decreased citrus supply and demand, chronic tree losses across markets, and significant regional economic distress.

• What can consumers do to support the citrus industry and prevent the spread of ACP and Citrus Greening?

  Buy disease-free citrus plants from trusted and certified nurseries in their areas. Plant them in well-drained soil when they are active growing, care for them properly by following recommended tree care guidelines, implement biosecurity measures that reduce the risk of introducing other plant pests and diseases to healthier areas gradually, and consume & advocate the consumption of more locally grown orchard produce to increase trust in the industry.

• Are there any known predators of Asian Citrus Psyllid that can help control its population?

  There are several beneficial insects known to prey on or parasitize ACPs, including Asian ladybugs, black lady beetles, lacewings, and spiders. However, the role of natural predators in managing population control is limited, and chemical intervention might be required for efficiency.