The discovery of gumming disease of sugarcane in Australia.

Sugarcane is one of Australia's major agricultural industries, with approximately 95% of the crop being grown in Queensland and the remainder in northern New South Wales. In the last decade of the nineteenth century, cane growers in northern New South Wales started to see a new disease that resulted not only in the death of plants but also in difficulties in the extraction of sugar. Theories about the cause abounded, but investigations by the New South Wales vegetable pathologist Nathan Cobb revealed that the disease, previously unknown to the world, was caused by a microbe in the creamy 'gum' that could be commonly found in the vascular tissues of affected stalks. He named the organism Bacillus vascularum (now known as Xanthomonas axonopodis pv. vasculorum). For some time after, the disease was known as 'Cobb's gumming disease of sugarcane'. The Australian bacteriologist Robert Greig-Smith was not convinced that Cobb had conclusively demonstrated that B. vascularum was the culprit, mainly because he did not satisfy Koch's Postulates. However, the American bacteriologist Erwin Frink Smith came to Cobb's rescue when he proved beyond doubt that B. vascularum was to blame. The disease is now known simply as 'gumming disease of sugarcane'. At the start of the decade of 1890, sugarcane growers in southern Queensland and northern New South Wales began to notice a serious disease affecting their crops. American-born Nathan Cobb, who was the New South Wales Government Vegetable Pathologist, discovered that a bacterium, now known as Xanthomonas axonopodis pv. vasculorum , was the cause of the disease. Although others were not convinced that Cobb had conclusively proved that the bacterium was the causal agent, it was for many years known as 'Cobb's gumming disease of cane'. [ABSTRACT FROM AUTHOR]