Characteristic of Oviposition and Effect of Density Suppression by Yellow-colored Sticky Trap on Ricania shantungensis (Hemiptera: Ricaniidae) in Blueberry

Abstract

This study was conducted to investigate the characteristics of oviposition and the effect of density suppression by yellow-colored sticky trap on Ricania shantungensis in blueberry. The occurrence of an egg mass of R. shantungensis in the upper, middle and lower region were 56.6~60.2%, 23.8~28.1% and 11.7~19.7%, respectively. The number of egg masses in the branch was investigated. Percentage of the branch with one egg mass was greatest (50.9%) than with two (20.5%), three (14.6%) and over four (14.0%). The effect of yellow-colored sticky trap to reduce the number of R. shantungensis egg masses in blueberry was also investigated. In a month after yellow sticky trap installation, 17.1 adults of R. shantungensis were attracted per trap. Moreover, the number of egg masses on a tree in yellow-colored sticky trap plot was much lower (0.4) than control (1.3). Consequently, this result shows that use of yellow-colored sticky trap may contribute to decrease ovipisotion rate of R. shantungensis in blueberry.

Determination of an optimum sampling unit of Ricania shantungensis (Hemiptera: Ricaniidae) eggs in persimmons

“…The reasons for this phenomenon were new branches were mainly developed in upper positions in blueberries and adult could better approach upper locations rather than middle or lower ones. The results of both studies [ 9 , 11 ] could be explained by an ecological characteristic of R . shantungensis that its adults have the high ovipositional preference for newly developed branches [ 9 , 15 , 16 ].…”

“…There were conflicting results [ 9 , 11 ] for within-tree distribution of R . shantungensis eggs, especially for vertical directions.…”

“…shantungensis adults could approach all vertical branches. However, Kim et al [ 11 ] found that R . shantungensis eggs were located more frequently in upper crowns of blueberries.…”

“…This study [9] also showed that the within-tree distribution of R. shantungensis eggs were not different vertically and horizontally. However, Kim et al [11] found the most R. shantungensis eggs on upper crown within a blueberry tree. This discrepancy indicates that within-distribution of R. shantungensis eggs would be different on persimmons compared to chestnuts.…”

“…shantungensis eggs were not different vertically and horizontally. However, Kim et al [ 11 ] found the most R . shantungensis eggs on upper crown within a blueberry tree.…”