According to UNODC, diseases of opium poppy are a normal occurrence in Afghanistan. Farmers report various degrees of damage to their crops in practically all years and regions since UNODC began systematic yield surveys (UNODC 2010d). In the spring of 2010, a fungal disease was speculated to be the possible cause of an opium-poppy blight in Afghanistan. The poppy plants exhibited wilting and other disease symptoms that appeared to be consistent with a fungal infection. Tests of diseased tissues identified two Fusarium species, but they were probably secondary colonizers of the decaying tissue rather than the cause of the disease. C. papaveracea/B. papaveris, which has been linked with past diseases of opium poppy in Afghanistan, was not detected (personal communication, Justice Tetty, UNODC, November 19, 2010), but it was noted that the tissue samples examined were of poor quality (personal communication, Eric Boa, CABI, November 25, 2010).

The UN Afghanistan Opium Survey of 2010 reported that opium production was 48% lower than in 2009 (UNODC 2010d) although the overall area under poppy cultivation remained the same. Disease was considered a major contributor to the reduction in opium yield, but farmers also reported losses due to frost, drought, and pests, such as aphids, other insects, and worms. Poppy capsules were fewer and smaller than in previous years. It is important to note that diseases in major growing areas affected opium poppy plants at the late stage of plant development. The diseased plants were described as exhibiting wilt symptoms with yellowing of leaves, drooping, and finally desiccating completely, all of which are indicative of a collar (stem-root interface) or upper root rot. Those symptoms are consistent with the ones observed previously in the region in connection with fungal infections (UNODC 2010d) but are inconsistent with the typical symptoms of infection by C. papaveracea/B. papaveris. The southern region was the most affected: about 42% of the area under opium cultivation was damaged. The western region was also affected by diseases but to a much smaller degree. In the west, a combination of factors, including frost, played a role, according to farmer reports (UNODC 2010d).

On the basis of the foregoing account, the cause of the reduction in opium production in 2010 in Afghanistan is unknown. Diseases, drought, frost, and pests might have contributed to it. Adverse weather conditions (such as frost and drought) might have predisposed the 2010 crop in different parts of Afghanistan to diseases. Without conclusive evidence based on positive identification of the pathogen, C. papaveracea/B. papaveris could not be implicated in the 2010 Afghan poppy blight epidemic. Therefore, it is not possible to gain any insight from this epidemic to guide the use of C. papaveracea/B. papaveris as a mycoherbicide.

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