Acholeplasmosis

Causative agent and disease type
Acholeplasma laidlawii is a microorganism belonging to the class Mollicutes. Lacking a cell wall, this pathogen is classified within the phytoplasma group, which are specialized bacteria that inhabit the sieve elements of the plant phloem. It induces systemic infection, fundamentally altering the plant's metabolic pathways and hindering the translocation of assimilates throughout the organism.

Host range
This pathogen has a wide host range, affecting various botanical families. It primarily targets economically important crops such as potatoes, tomatoes, sunflowers, and forage grasses. Furthermore, it often persists in asymptomatic wild weeds, which serve as essential reservoirs for the pathogen, facilitating its survival in the environment during the off-season.

Symptoms and signs of infection
The manifestation of the disease is typically characterized by stunted growth, chlorosis, and leaf deformation. A common symptom is the development of "witches' brooms," where the plant exhibits excessive branching and shortened internodes. Infected plants often show poor flower development, sterility, or the production of malformed fruits, leading to significant physiological decline.

Development and economic impact
The dissemination of Acholeplasma laidlawii is largely dependent on sap-sucking insect vectors, primarily leafhoppers and aphids. These insects acquire the pathogen from infected plants and transmit it to healthy ones during feeding. The disease causes severe economic loss by reducing both the yield and the quality of the harvest, frequently rendering infected plants non-productive.

Prevention and control measures

• Rigorous control of weeds to eliminate environmental reservoirs.
• Insecticide applications to suppress populations of insect vectors.
• Use of healthy, certified propagation material to prevent initial entry.
• Implementation of crop rotation and maintaining spatial distance between fields.
• Prompt roguing of symptomatic plants to minimize the spread of the pathogen.