New Host Record of Formicococcus polysperes Williams (Hemiptera: Pseudococcidae): An Emerging Pest of Taro Colocasia esculenta (L.) Schott from India

The mealybug Formicococcus polysperes Williams (Hemiptera: Pseudococcidae) was reported for the first time attacking rhizomes of Colocasia esculenta (L.) Schott from Nagaland state, India. In initial infestation, the tender rhizomes were observed to be covered with whitish powdery mass of mealybugs. In severe infestation, the entire underground portions of the plant were covered with mealybugs along with the black sooty mould in patches on plant parts. The infected plants showed symptoms of yellowing and withering of leaves accompanied with underdeveloped rhizomes which eventually dried prematurely. Results on survey of fields and a nearby storage facility revealed up to 52% crop loss due to its infestation. Among the eighteen genotype screened against F. polysperes, none of the genotype was found to be tolerant as average number of mealybug population ranged between 310 and 588 per rhizome (30–40 g weight). In this paper, we describe the damage symptoms, results of host screening and the diagnostic morphological characteristics of F. polysperes to facilitate its quick and reliable identity in future.