Spatial Distribution and Abundance of the Mealybug, Phenacoccus solenopsis (Hemiptera: Pseudococcidae) Infesting Okra Plants

Document Type : Original Article

Authors

1 Department of Scale Insects and Mealybugs Research, Plant Protection Research Institute, Agricultural Research Centre A.R.C., 12511 Giza, Egypt

2 Zoology Department, Faculty of Science, South Valley University, 83523 Qena, Egypt.

Abstract

Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae), poses a significant threat to newly targeted okra plants. This pernicious pest can be found on all plant parts, leading to desiccation and ultimate demise. Our study aimed to examine the spatial distribution pattern of P. solenopsis infestation in okra plants, specifically focusing on the Balady cultivar, over two consecutive seasons (2021-2022) in the Luxor region of Egypt. We employed insect counts and determined the percentage of infested plants to characterize the insect population. Our findings revealed that P. solenopsis infestation on okra plants emerged five weeks after planting (WAP) and persisted until harvest in every season. During each season, we observed three distinct peaks in population numbers and infestation rates of P. solenopsis. Notably, the initial season exhibited higher overall quantities of P. solenopsis compared to the subsequent season. At 20 WAP, we observed the most suitable time for population estimates to increase, while at 5 WAP, it was the least favorable for activity during both seasons. Statistical analysis of variance demonstrated significant variations in P. solenopsis population estimates and infestation percentages across different inspection periods. Additionally, through nonlinear regression analysis, we elucidated the relationship between P. solenopsis numbers and phenological development. Data were evaluated using dispersion measures, and all P. solenopsis dispersal indices had substantial aggregated behavior and were strongly related to the host's phenological evolution during each season. Based on the available data, we can develop effective strategies for monitoring and controlling mealybugs in okra plants.

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