Beginning in 2006, the Pine Wilt Disease (PWD) international conference has been held three times every three years so far, in such venues as Lisbon (2006), Portugal and China (2009), and in Germany (2013), making remarkable progress with each conference in both PWD research activities and cooperation within member countries. And this year, it celebrates the fourth time. 

On behalf of the National Institute of Forest Science (NIFoS), we are very proud to host “the 2016 international conference of Pine Wilt Disease”, which takes places from August 29 to September 2, 2016, in Seoul, South Korea. As the PWD Working Party, IUFRO unit 7.02.10, we have tried to perform a variety of activities by collaborating with various research communities of PWD worldwide. In particular, the PWD international conference aims to provide the opportunity to bring together people interested in a thorough understanding of the pathogens and diseases in general, and in the development of new tools and approaches that may offer solutions for the integrated control of diseases in the ecosystems with the lowest impact on the forest environment, as well as in a fruitful academic accomplishment. 

PWD has been a serious problem since first noted in early 1990s in Japan, and now it is largely blamed for the massive loss of pines in many other countries worldwide, including East Asia and Europe. PWD is known to be caused by pine wood nematode (Bursaphelenchus xylophilus). The disease is transferred fast from infected trees to healthy trees by pine sawyer beetles (Monochamus spp.) carrying the nematode, as they feed on the bark and foliage of susceptible pines. The nematode and sawyer beetles may begin to emerge even from the dead, infected tree and move to a new host, can also survive even in stumps or firewood for a time, which makes the management and control of PWD somewhat complicating. In addition, incidence and severity of PWD symptoms may increase during times of drought and high temperatures during summer months. 

Though the scientific contributions of the conference have covered a variety of interdisciplinary topics, including the integrated management and control of PWD, global climate changes and its potential impact on PWD, strategies for disease resistance and so on, there is still a long way for us to go to successfully address such issues. In this sense, the conference is very timely and meaningful. Throughout the duration of this conference, we hope to create a favorable atmosphere where everyone, ranging from researchers, students, professionals and to decision makers, can share their experiences and lessons in their own field of expertise, and exchange ideas so as to facilitate establishing working partnerships. To achieve this, your presence to the 4th international PWD conference in Seoul, South Korea, will be very crucial and certainly contribute to making this conference successful. 

We would like to take this opportunity to thank all of participants, session organizers, secretary staff, committee members and so on, for their hard work and dedication to organizing this significant conference. We hope all of you will enjoy the 4th international PWD conference and your stay in Seoul!