VG01096 Poster – Trichoderma optimisation

Trichoderma atroviride isolate C52 has shown good antagonistic activity against Sclerotium cepivorum by nutrient competition.

Before this biocontrol agent is evaluated for control of onion white rot on bunching onions, it is important to determine its ability to survive in soils used for producing short-season onions at levels desirable for effective biocontrol.

This poster describes the determine the ability of T. atroviride C52 to colonise different soil types and the effect of soil amendments on biocontrol growth in sandy soil.

Summary :

• Two weeks after sowing, Trichoderma grew at levels considered necessary for effective biocontrol only in the black and clay soils.
• In general, Trichoderma growth was less than optimal in untreated sandy soils.

  This was probably due to the low content of organic matter.

• Incorporation of pellets containing humic acids or pelleted manure with Trichoderma prills at sowing enhanced the growth of Trichoderma in sandy soil.
• Amending sandy soil with 1-10% (w/w) of fresh composted chicken manure affected the growth of Trichoderma.
  
• Therefore nitrogenous materials (e.g. fertilisers, poultry manure) should not be applied close to Trichoderma applications.

Acknowlegements :

There were many people and organisations that provided assistance to make this research possible. They include:

• DPI personal Craig Murdoch and Slobovan Vujovic for assistance with technology transfer activities.
• Peta Easton for technical assistance and Dr. Liz Minchinton for collection of survey data in NSW and SA.
• John Hunt of Agrimm Technologies Ltd for his valuable advice on biocontrol trial preparation and Rob Stanic for arranging supply of Trichopel Ali52 and other products for field trials.
• Doug Wilson and Paul Geister (NuFarm) for advice with fungicides and Elliott Chemical and Serve- Ag Research for supplying DADS for field trials.
• Peter DalSanto (AgAware Consulting) for advice with fungicides and processing minor use permits for fungicide treatments.
• Soheir Salib, Department of Primary Industries, Knoxfield for assistance in establishing and harvesting field trials and reviewing this manuscript.
• The spring onion growers in Victoria who graciously allowed trials on their farms and provided assistance in their establishment, maintenance and harvest.
• Agrochemical companies for providing samples of fungicides and other companies for supplying biological products for laboratory, glasshouse and field work.

The authors thank the members of the Steering Committe, Rocky Lamattina, Tony Lamattina, Craig Arnott, Karl Riedel and others for their valuable advice to this project.

This project was commissioned by Horticulture Australia Limited with funds frrom the Vegetable R&D levy..

The Australian Government provides matched funding for all HAL’s R&D activities.