Rhizoctonia bare patch and root rot disease of wheat, caused by Rhizoctonia solani AG-8, develops as distinct patches of stunted plants and limits the yield of direct-seeded (no-till) wheat in the Pacific Northwest of the United States. At the site of a long-term cropping systems study near Ritzville, WA, a decline in Rhizoctonia patch disease was observed over an 11-year period. Bacterial communities from bulk and rhizosphere soil of plants from inside the patches, outside the patches, and recovered patches were analyzed by using pyrosequencing with primers designed for 16S rRNA. Taxa in the class Acidobacteria and the genus Gemmatimonas were found at higher frequencies in the rhizosphere of healthy plants outside the patches than in that of diseased plants from inside the patches. Dyella and Acidobacteria subgroup Gp7 were found at higher frequencies in recovered patches. Chitinophaga , Pedobacter , Oxalobacteriaceae ( Duganella and Massilia ), and Chyseobacterium were found at higher frequencies in the rhizosphere of diseased plants from inside the patches. For selected taxa, trends were validated by quantitative PCR (qPCR), and observed shifts of frequencies in the rhizosphere over time were duplicated in cycling experiments in the greenhouse that involved successive plantings of wheat in Rhizoctonia -inoculated soil. Chryseobacterium soldanellicola was isolated from the rhizosphere inside the patches and exhibited significant antagonism against R. solani AG-8 in vitro and in greenhouse tests. In conclusion, we identified novel bacterial taxa that respond to conditions affecting bare patch disease symptoms and that may be involved in suppression of Rhizoctonia root rot and bare batch disease.

This article is a history of dryland wheat (Triticum aestivum L.) farming in the low‐precipitation (<300 mm annual) region on the Columbia Plateau of the Inland Pacific Northwest (PNW) of the United States. Numerous technological advances, environmental problems, and sociological factors influenced wheat farming since its inception in 1880. The wheat‐based economy traces back to the pioneers who faced many challenges that included scarcity of water and wood, unprecedented wind erosion, drought, and minimal equipment. Throughout the years, major technological breakthroughs include: (i) horse (Equus caballus) farming to crude crawler tractors to the 350+ horse power tractors of today, (ii) transition from sacked grain to bulk grain handling, (iii) nitrogen fertilizer and herbicides, (iv) the rotary rodweeder, and (v) the deep furrow split‐packer drill to allow early planting of winter wheat into stored soil water. Cultural practices have evolved from repeated passes with high‐soil‐disturbance tillage implements to today's conservation tillage management. The 2‐yr winter wheat–summer fallow rotation continues as the dominant cropping system as it is less risky and more profitable than alternative systems tested so far. Improved wheat cultivars for deep furrow planting continue to be developed with good emergence, disease resistance, winter hardiness, grain quality, and other values. In the past 125 yr, average farm size has grown from 65 to 1400 ha and wheat grain yield increased from <1.0 to 3.4 Mg ha⁻¹. Since the 1930s, government farm programs have provided unwavering support that, in the last several decades, accounts for about 40% of gross farm income.