A snapshot of Psa

Abstract

This collaborative project is evaluating the potential for beneficial microbes and elicitors to reduce damage to kiwifruit from Psa disease. The project includes foliar application of selected candidate micro-organisms and elicitors, root inoculation with Trichoderma endophytes, root treatment with elicitors and combination treatments. Assays have been developed using kiwifruit seedlings challenged with Psa by stab-wounding the stem or spraying. Systemic plant responses, wound protection, protectant activity of biological control agents (BCAs), elicitors and natural products against Psa are being assessed. Elicitor treatments, mixtures of BCAs spray-applied to the shoot, and several Trichoderma root endophytes have shown promise in reducing Psa in seedling assays and will be tested in Psa-infected orchards. Trichoderma root endophytes have reduced nursery and plantation diseases (by 25–60%) and have increased plant growth (by 5–15%) in New Zealand and South East Asia. The best root endophytic Trichoderma strains have become „standard operational practice‟ for sustainable plantation forestry in the Planted Forest Zone of Malaysian Borneo.