Japanese scientists from the Ehime Research Centre in Japan visited New Zealand this week on a Zespri-hosted tour. They were interested in learning about Psa control practices, resistance testing and varietal assessment within breeding programmes, and welcomed the opportunity to build knowledge and strengthen relationships with researchers and Gold3 growers.

Technical Senior Researcher, Nobuki Miyata and Pathology Senior Researcher, Mitsuo Aono, met with KVH and members of the Zespri Innovation team to discuss research opportunities. Pollen cleaning and assessment of endophytes and other biological control methods for Psa were seen as possible areas for future collaboration.

Access to clean pollen is a challenge for Japanese growers. Around half of their orchards have no males and rely solely on artificial pollination.

Psa-V (biovar 3) was identified in Japan for the first time in 2014 and is now present in seven Japanese prefectures. Other Psa strains (biovar 1 and biovar 2) are also present in Japan and appear more virulent to Hayward varieties than Psa-V. They have also identified a new strain (biovar 5) which is of lower virulence to biovar 3, but still causes leaf spotting and flower infection.