First report of Neopestalotiopsis clavispora causing leaf spot on macadamia (Macadamia integrifolia) in China.
Macadamia (Macadamia integrifolia) is an economically important plant around the world, especially in China, because of its nutritional properties. In March 2018, a severe leaf spot was observed in Yunnan, China. The disease severity was estimated at around 15%. The disease began to develop from the tip or from the margin of the leaf. Initial disease symptoms on leaves were circular to irregular, grayish white, dark brown around, which enlarged and coalesced, covering an extensive leaf area. Lesions showed abundant acervuli on the leaf surface. Twenty random symptomatic leaves were collected for pathogen identification. Based on morphological characteristics, molecular data (sequence analysis of the rDNA internal transcribed spacer, β-tubulin and TEF1-α loci) and pathogenicity tests, the causal agent was identified as N. clavispora. This pathogen has been reported on many other host plants in the world. It has been reported as the causal agent of leaf spot on Ligustrum lucidum in China and on M. integrifolia in Brazil. This is thought to be the first report of N. clavispora attacking macadamia in China.