Abstract
Even though the optimum sampling methods for invasive pests are very important in newly invaded areas, the standard sampling unit of Ricania shantungensis is still undeveloped in persimmons. Among all developmental stages of R. shantungensis, the egg has close relationship between its density and subsequent tree damage. Thus, this study was conducted to suggest an optimum sampling unit for R. shantungensis eggs in persimmons based on characteristics of its within-tree distribution pattern. The within-tree distribution pattern was characterized with 60 persimmon trees by cutting 12 branches at three vertical levels (low, middle, and high) in four horizontal criteria (east, west, south, and north) per tree. The sampling units were determined based on coefficient of variation (CV) and coefficient of determination (r2) calculated from egg mass numbers per 10 cm from the tip within a branch. In numbers of R. shantungensis egg masses, there was no significant difference (P > 0.05) horizontally, but significant (P < 0.05) difference vertically. More R. shantungensis eggs were found on terminal branches of each trunk. The 60 cm from the tip of branches in the terminal positions of each trunk was selected as the optimum sampling unit for R. shantungensis in persimmons because this unit has the lowest CV value and more than 0.9 of r2 value. Even though the optimum sample number per tree should be determined field-specifically, it would be acceptable to sample two or three branches by considering this pests’ recognizable damage level. This small sampling unit could make the sampling of R. shantungensis become more economical, precise, and consistent in persimmon fields.
Highlights
After the first report in 2010 of outbreak for an invasive species, Ricania shantungensis (Hemiptera: Ricaniidae), this pest became an economically important pest in Korea [1]
Sampling unit of Ricania shantungensis in persimmons terminal branches than basal and middle ones. This result indicates that any living terminal branches regardless of horizontal directions within a tree would be suitable for sampling of R. shantungensis eggs in persimmon fields
60 cm from the tip of branches in the terminal positions of each trunk within a tree should be used as the sampling unit for R. shantungensis eggs in persimmon fields
Summary
After the first report in 2010 of outbreak for an invasive species, Ricania shantungensis (Hemiptera: Ricaniidae), this pest became an economically important pest in Korea [1]. Serious economic damage has been reported mainly in fruits trees because R. shantungensis can lay eggs only in arboreal plants and its oviposition mainly causes damage by blocking the currency of plant saps in newly developed branches [2]. This pest is known to have host plants of 138 species in 62 families including economically important fruits crops. Sampling unit of Ricania shantungensis in persimmons such as persimmon, chestnut, peach, apple and so on [3] This broad host range with limited natural enemies might allow R. shantungensis to quickly establish populations in new areas [1]. The biggest persimmon cultivation areas in Korea are already neighboring the outbreak areas of this pest [1]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
