Development of Effective Screening Method for Efficacy Test of Trunk Injection Agents Against Pine Wood Nematode, Bersaphelenchus xylophilus in Japanese Black Pine, Pinus thunbergii

Abstract

Pine wood nematode (PWN), Bursaphelenchus xylophilus is one of the most serious pests of pine tree. Trunk injection of some nematicides in tree is well known as an effective control method. However there are some limitating factors which hindering the efficacy of trunk injection in field or potted tree. In this study we suggested easy and useful alternative screening methods of nematicides against PWN. Reproduction of PWN was influenced by tree twig moisture (high reproduction in high moisture trig) and paraffin coating was 78.6% reduced moisture loss in tested twig. There were no reproduction different in up and down site from infection site of twig at 1 month after inoculation of PWN and also distance (5 and 10 cm) from inoculation site of PWN did not influence the reproduction of PWN. Numbers of reproduced PWN were higher with decreasing diameter of twig. Numbers of reproduced PWN were similar to P. thunbergii and P. densiflora. However reproduction was increased depending on high inoculation density and longer propagation period. When inoculation of PWN on cut twig injected with emamectin benzoate 2.15% EC and morantel tartrate 8% SL in trunk of Pinus thunbergii in the field, PWN number were significantly reduced than untreated control. We suggest this screening method for PWN control agents.

Comparative Bioactivity of Emamectin Benzoate Formulations against the Pine Wood Nematode, Bursaphelenchus xylophilus

“…The second bioassay was conducted the same way as described above but, in pine tree twigs according to the method of Shin et al (2015) . Briefly, nematode populations were pre-exposed to the above-mentioned chemical concentration preparations for 24 h at 25°C, and were subsequently washed with sterilized water before being homogenized to the targeted nematode numbers.…”

“…Trunk injection with especially the naturally occurring broad-spectrum avermectins (abamectin and emamectin benzoate) offers a direct nematicidal effect on the target nematode and is relatively seen as an environmentally friendly approach than direct aerial applications practiced in control of insect vector. These chemicals are known to offer a persistent nematicidal effect over successive number of years (Kwon et al, 2011;Lee et al, 2009;Shin, 2008;Takai et al, 2000Takai et al, , 2004.…”

The Potency of Abamectin Formulations against the Pine Wood Nematode, Bursaphelenchus xylophilus

“…The second bioassay was conducted in a similar way as described above but, in pine tree twigs according to the method of Shin et al (2015) . Nematodes were pre-exposed to the selected varying concentrations as described above before being inoculated in pine twigs.…”

Nematicidal Activity of Eclipta prostrata Extract and Terthiophene against Pine Wood Nematode, Bursaphelenchus xylophilus

“…따라서 소나무재선충의 감염을 막기 위해서 는 현재까지는 살선충제의 나무주사가 가장 현실적인 방법 이다 (Shin et al, 2015). 소나무재선충병을 예방하기 위한 나무주사 약제로는 emamectin benzoate나 abamectin, morantel tartrate 같은 살선충 제들이 이용되고 있는데 (Takai et al, 2003;Lee et al, 2009) 환경에 대한 위해성이나 비용적인 측면 때문에 저비용으로 환경 위해성이 낮거나 없는 대체 방제제에 대한 요구도가 증가되고 있는 실정이다 (Park et al, 2007;Lee et al, 2015).…”