Ground Cover Supplement : GC Supplement - New farm products and services
9 NEW FARM PRODUCTS & SERVICES GROUND COVER OBJECTIVE MEASUREMENT & QA Improved quality assurance for inoculants To keep pace with changes in the manufacture of rhizobial inoculants an enhanced quality assurance system is being developed to increase grower confidence in these products By Roz Deaker THE INOCULATION OF legumes with rhizobia to provide biologically 'fixed' nitrogen from the atmosphere is one of the great success stories of Australian agriculture. Each year approximately 2.5 million hectares are sown with inoculated legumes. A program of quality control and assurance for rhizobial products has operated for more than 50 years. However, recent developments within the inoculant industry and with rhizobial products have initiated the need for a more extensive quality assurance (QA) program. QA of rhizobial products is managed by the Australian Legume Inoculants Research Unit (ALIRU), based at the NSW Department of Primary Industries laboratories at Gosford. Currently manufacturers of rhizobial inoculants provide batch samples to ALIRU for quality testing on a voluntary basis. This system of QA is unique to Australia and differs from the situation in the US, where there is no regulation, and Canada, where rhizobial products are fully regulated. It has been identified that the current system has several constraints. Commercial batches of inoculant are tested and approved at the point of manufacture. Details of test results are commercial- in-confidence and little information is relayed to the grower. Further, new formulations are creating challenges to current QA practices and the current QA system relies on manufacturer cooperation. Until recently almost all rhizobial inoculants sold in Australia were peat-based inoculants. Following considerable research and development to produce formulations that offer improved ease of application and storage, granular, liquid, and freeze- dried inoculants have been introduced. Although retail surveys of inoculant quality are carried out, it has been proposed that the QA system based at the point of sale needs to be more comprehensive. Retail surveys indicate that the quality of inoculants can be variable in retail conditions and this information is of relevance to farmers. Generally the quality of peat-based inoculants is high, with more than 93 per cent of retail samples tested over the past three years meeting the ALIRU numerical standard of 109 viable rhizobia per gram. Quality of pre-inoculated legume seed on the other hand is generally low and the GRDC is currently supporting research to improve the quality of these and other newer inoculant formulations. The proposed new structure is based on maintaining industry self-regulation, but introducing the concept and the discipline of a trademark to replace the current ALIRU approval. The extended program would need guaranteed, independent funding. Such an independent QA system would test samples of all rhizobial inoculant types on sale in Australia, whether tested at the point of manufacture or not, and the results of these tests would be communicated to growers. It is proposed that a packet labelling system similar to the Heart Foundation's 'tick' of approval on food be initiated to indicate inoculant quality. PHOTO: ROZ DEAKER Microbiological techniques using a combination of specific antibodies and selective media, together with molecular techniques, are currently being tested for application in quality assurance of rhizobial and non-rhizobial inoculants. A NEW LABEL IS PROPOSED TO INDICATE INOCULANT QUALITY. QA would provide results on: the recommended rhizobial strain for each legume group; the number of viable rhizobia per gram or millilitre in a packet; the presence of any contaminating organisms; the optimal moisture potential for strain growth and survival in the carrier medium during storage; and the strain's capacity to 'fix' nitrogen with its intended host at that time.
GC Supplement - Agronomy
GC Supplement - Feedgrains