A newly published pictorial guide assists California citrus growers in distinguishing the damage caused by early-season pests on different citrus varieties. The guide, titled "Comparing the Fruit Rind Scarring That Three Early-Season Pests Cause in Mandarin Species and Sweet Orange," was released by the University of California Agriculture and Natural Resources.
Early-season pests such as katydids, earwigs, and citrus thrips can inflict rind scarring on developing fruit, which may result in downgrading at packinghouses and economic losses. Effective management of these pests is essential for growers.
While several resources like the "Photographic Guide to Citrus Fruit Scarring" from 2003 exist, they primarily focus on sweet oranges. The increase in mandarin acreage in California highlighted the need for specific identification of rind scarring on these varieties.
Research led by Postdoctoral Scholar Bodil Cass from the University of California Davis, in collaboration with the Lindcove Research and Extension Center, evaluated grower data and conducted experiments. This work culminated in a photographic guide detailing how early-season pests affect mandarin species compared to sweet oranges.
The research found that the damage caused by pests varies between mandarin types, such as Tango and clementine. Notably, katydids do not cause feeding damage on Tango or Afourer mandarins. However, katydid damage on clementines resembles worm damage on sweet oranges, potentially leading to fruit splitting and dropping.
Source: Citrus Industry
