Investment

Net Form of Net Blotch (NFNB; Pyrenophora teres f. teres) and Spot Form of Net Blotch (SFNB; Pyrenophora teres f. maculata) have a high capacity to adapt to host resistance genes. Therefore, new strains can emerge that can quickly become a significant industry problem. Continued national monitoring for new virulent strains of concern is a long-standing recommendation. Program 1 of the GRDC Barley Net Blotch Consortium (BNBC) will continue screening of Australian commercial cultivars and host differential sets against local and exotic net blotch pathotypes through collaborations with national and international disease nurseries. This will provide industry with knowledge on the susceptibility to, and improved preparation for, new emerging virulent pathotypes before significant crop losses occur. It will also feed valuable knowledge and resources into the other Programs of the GRDC BNBC.

Screening at the adult stage is most relevant to industry and allows identification of Adult Plant Resistance (APR; also known as 'quantitative resistance') genes, which tend to be more durable. Screening at the adult stage generally occurs in field nurseries inoculated by infected stubble. Thus, such traditional screens are low throughput as they occur only once per year, are prone to environmental variation, with inconsistent infection rates. This investment will develop robust protocols for screening NFNB and SFNB infections at adult stage within Controlled Environmental Rooms (CER). This will allow for season independent, multiple screens per year (i.e. accelerated throughput), in environments adjusted to be the most conducive to infection (i.e. consistent infection rates), using inoculum dispersed with a spray (i.e. more repeatable and informative). Additionally, running these screens in a contained room provides the advantage of being able to test non-regional virulent isolates (as opposed to only using local isolates in field nursery tests). Sharing of these protocols with researchers and industry across the country will increase national screening capacity and improve reproducibility in the data generated.

A 'Barley Net Blotch Industry Report' will summarise key findings during the course of the investment and be disseminated to the broader Australian barley community including growers and advisors.