Study on the damage by pine wood nematode in black pine trees

Abstract

The distribution and form of pine wood nematode (PWN) were investigated in Jinju-si and Sacheon-si areas, where infested with pine wilt disease (PWD). The average PWN population per g of the tubulation part in the wilted Japanese balck pine were 381.2 and 341 in Jinju-si and Sacheon-si, respectively. The PWN population per g of affected Japanese black pine with wilt rate below 60% were 556 and 518 in Jinju-si and Sacheon-si, respectively. The ratios of PWN and other plant-parasitic nematode in the wilted Japanse black pines were 48% vs. 52% in Jinju-si and 53% vs. 47% in Sacheon-si after exposure to PWD for 1 year. The survivorship of pine wood nematode in the sampled trees after 1 year was 0-10% in the Jinju-si area and 5-20% detected in the Sacheon-si area. In the forest areas affected by PWN, the highest survival rates were 37.2% and 39.8% at 25 cm diameter at breast height (DBH) in Jinju-si and Sacehon-si, respectively, while the highest wilt rates were 30.5% and 28.3% at 30 cm DBH in Jinju-si and Sacehon-si, respectively. ? 2017 Czech Academy of Agricultural Sciences. All rights reserved.