High-resolution melt and morphological analyses of mealybugs (Hemiptera: Pseudococcidae) from cacao: tools for the control of Cacao swollen shoot virus spread

作者：Wetten Andy^*; Campbell Colin; Allainguillaume Joel

来源：Pest Management Science, 2016, 72(3): 527-533.

DOI：10.1002/ps.4017

• mealybugs
• Pseudococcidae
• Theobroma cacao
• Cacao swollen shoot virus
• DNA barcoding
• high-resolution melt

BACKGROUNDMealybugs (Hemiptera: Coccoidea: Pseudococcidae) are key vectors of badnaviruses, including Cacao swollen shoot virus (CSSV), the most damaging virus affecting cacao (Theobroma cacao L.). The effectiveness of mealybugs as virus vectors is species dependent, and it is therefore vital that CSSV resistance breeding programmes in cacao incorporate accurate mealybug identification. In this work, the efficacy of a CO1-based DNA barcoding approach to species identification was evaluated by screening a range of mealybugs collected from cacao in seven countries.
RESULTSMorphologically similar adult females were characterised by scanning electron microscopy, and then, following DNA extraction, were screened with CO1 barcoding markers. A high degree of CO1 sequence homology was observed for all 11 individual haplotypes, including those accessions from distinct geographical regions. This has allowed the design of a high-resolution melt (HRM) assay capable of rapid identification of the commonly encountered mealybug pests of cacao.
CONCLUSIONSHRM analysis readily differentiated between mealybug pests of cacao that cannot necessarily be identified by conventional morphological analysis. This new approach, therefore, has potential to facilitate breeding for resistance to CSSV and other mealybug-transmitted diseases.

• 出版日期2016-3