In almond: Symptoms include early flowering, stunted growth, leaf rosetting (a disease symptom characterized by short, bunchy growth habit due to shortened internodes and reduction in leaf size), dieback, off-season growth, proliferation of slender shoots, witches"-broom, and smaller pale green leaves (Abou-Jawdah et al., 2002). Witches"-broom symptoms arise mainly from the trunk or roots (Abou-Jawdah et al., 2002). The phytoplasma has also been detected in symptomless almond hosts (Abou-Jawdah et al., 2002).
Some almond cultivars are more susceptible to "Ca. P. phoenicium" than other cultivars. In Lebanon, the Alwani and Awja cultivars are highly susceptible and developed severe symptoms, and the Kachabi cultivar is less severely affected (Verdin et al., 2003). The susceptibility of almond cultivars grown in the United States is not currently known.
In peach/nectarine: Symptoms early in the growing season include premature flowering followed by the early development of buds (Molino-Lova et al., 2011). Symptoms later in the growing season include: shoot proliferation, smaller leaves with a pale green color, abnormal flowers (phyllody), and witches"-broom symptoms in rare cases (Abou-Jawdah et al., 2010). Most infected trees do not set any fruit, but some trees bore a limited number of deformed fruits (Abou-Jawdah et al., 2010).