Resistance of ten Indonesian cassava cultivars to the cassava lacebug, Vatiga illudens (Drake) (Hemiptera: Tingidae), a newly invasive exotic species in Asia

The cassava lacebug, Vatiga illudens (Drake) (Hemiptera: Tingidae), is a pest that feeds on cassava foliage, significantly reducing the yield of tuberous roots. Recently introduced to Asia, this invasive exotic pest has been reported only in Indonesia, where it poses a serious threat to cassava cultivation. This study aimed to determine the resistance levels of ten Indonesian cassava cultivars to V. illudens. The leaf nutritional profile (proximate content), as well as phenol and hydrogen cyanide (HCN) content, were analyzed as potential factors affecting the biological parameters of V. illudens. Results from the choice test revealed that V. illudens adults exhibited a clear preference for certain cultivars, with the highest numbers observed on Gajah (10.00 individuals), Adira 1 (5.60 individuals), and Mentega (5.20 individuals). In contrast, adult numbers on the remaining cultivars were lower, ranging from 2.40 to 3.60 individuals. In the no-choice antibiosis test, the nymphal developmental period (from first instar to adult) ranged from 11.70 to 20.40 days, while adult longevity varied from 9.05 to 16.30 days. Leaf HCN content was the only chemical property found to be associated with the degree of resistance in cassava cultivars, with low-HCN cultivars like Gajah (9.66 mg/g) and Mentega (11.26 mg/g) being more preferred by V. illudens. The insect also exhibited faster development and extended adult longevity on these cultivars, leading to increased population growth. These findings are expected to provide valuable information for the management of V. illudens.