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Wheat is a crop of historical significance, as it marks the turning point of human civilization 10,000 years ago with its domestication. Due to the rapid increase in population, wheat production needs to be increased by 50% by 2050 and this growth will be mainly based on yield increases, as there is strong competition for scarce productive arable land from other sectors. This increasing demand can be further achieved using sustainable approaches including integrated disease pest management, adaption to warmer climates, less use of water resources and increased frequency of abiotic stress tolerances. Out of 200 diseases of wheat, 50 cause economic losses and are widely distributed. Each year, about 20% of wheat is lost due to diseases. Some major wheat diseases are rusts, smut, tan spot, spot blotch, fusarium head blight, common root rot, septoria blotch, powdery mildew, blast, and several viral, nematode, and bacterial diseases. These diseases badly impact the yield and cause mortality of the plants. This review focuses on important diseases of the wheat present in the United States, with comprehensive information of causal organism, economic damage, symptoms and host range, favorable conditions, and disease management strategies. Furthermore, major genetic and breeding efforts to control and manage these diseases are discussed. A detailed description of all the QTLs, genes reported and cloned for these diseases are provided in this review. This study will be of utmost importance to wheat breeding programs throughout the world to breed for resistance under changing environmental conditions.

Fusarium head blight (FHB; caused by Fusarium graminearum) is a destructive disease of wheat (Triticum spp.), barley (Hordeum vulgare), rye (Secale cereale L.), and triticale (×Triticosecale Wittmack) not only reducing their yield but also contaminating the grain with mycotoxins such as deoxynivalenol (DON). Developing varieties with genetic resistance is integral to successfully manage FHB. Triticale acreage worldwide is steadily increasing. However, the genetic diversity of triticale for FHB resistance is not well characterized. In the present study, a sequential screening of a set of winter triticale accessions from a global collection was done for their type‐2 FHB resistance and DON accumulation. In the first‐year screening, 298 triticale accessions were tested for FHB in an artificially inoculated, misted‐field nursery with high inoculum density. Most of the triticale accessions were susceptible to FHB, and only 8% of the accessions showed resistance in the field nursery screening. Next, the 24 resistant accessions identified in the nursery screening were tested for 2 years in greenhouse and 17 accessions showed significantly lower FHB severity in Year 2 and/or Year 3. These 17 resistant accessions were further tested for their FHB severity and DON accumulation in Year 4 in greenhouse and for DON accumulation in Year 5 in the field FHB nursery. Eight accessions showed significantly lower FHB severity and nine accessions showed DON accumulation of less than 1 mg/kg in Year 4 greenhouse testing. Eleven accessions had significantly lower DON concentration than the susceptible check in the Year 5 field screening. The resistant accessions common across all years identified in the study can be used for enhancing FHB resistance and reducing DON accumulation in triticale breeding programs. Core Ideas: A set of 298 triticale accessions was sequentially tested for FHB severity and DON content over multiple years.Only 2% of the accessions were found to be resistant and with low DON content across all the years.The robustly characterized accessions with low FHB severity and DON content can be used as sources of resistance. [ABSTRACT FROM AUTHOR]

Feeding the world's ever‐increasing population requires continuous development of high‐yielding and disease‐resistant cultivars of food crops such as wheat (Triticum aestivum L.). Speed breeding, which utilizes longer photoperiod times and higher temperatures, is a technique that accelerates plant development and is rapidly being adopted by wheat breeders across the globe to fast‐track cultivar development. Plant diseases are a major threat to crop production, and breeding for disease resistance is a major goal of crop breeders. Fusarium head blight (FHB), caused by Fusarium graminearum, is a major disease of small grain cereals, affecting their yield and quality. The aim of present work was to assess if speed breeding conditions can be used to accelerate reliable assessment of FHB severity and mycotoxin deoxynivalenol (DON) accumulation in wheat varieties. We screened a set of six spring wheat genotypes with different levels of genetic resistance (two moderately susceptible, two highly susceptible, one moderately resistant, and one resistant) for their response to FHB at 14 days after inoculation (dai) and 21 dai and DON accumulation under normal versus speed breeding conditions. FHB severity and DON accumulation were found to be highly correlated at all time points under normal and speed breeding conditions. Robust differentiation between resistant and susceptible genotypes could be achieved at 14 dai rather than the normal period of 21 dai, saving at least a week in phenotyping. Combined with the accelerated growth, flowering, and maturity under these conditions, efficient FHB screening and DON evaluation under speed breeding conditions will fast‐track development of resistant wheat varieties. Core Ideas: Speed breeding is increasingly being adopted by crop breeding programs.We evaluated spring wheat genotypes with different levels of genetic resistance for Fusarium head blight (FHB) and deoxynivalenol (DON) levels under speed breeding versus regular conditions.Reliable distinction could be made in FHB severity at 14 days after inoculation (dai) under speed breeding as compared to 21 dai under normal growth conditions.Growing and testing the plants under speed breeding conditions saved a total of 21–23 days as compared to regular conditions. [ABSTRACT FROM AUTHOR]