Effects of eyespot on the yield of winter wheat

Abstract

SUMMARYFor 4 successive years, cultivars of winter wheat differing in resistance to eyespot (Cercosporella herpotrichoides) and to lodging were grown in plots in which different levels of eyespot were induced by inoculating at different times. Lodging was either allowed, or prevented by growing the plants through nets. Yield losses were greatest in the most severely infected plots in which lodging was allowed; losses were reduced where infection was less severe or where lodging was prevented. In the year in which eyespot was most severe, there was a significant regression of yield on disease severity, even for the plots in which lodging was prevented; where lodging was allowed, regression lines were steeper for the lodging susceptible cultivars, but did not differ for the lodging resistant cultivars. Eyespot reduced the number of tillers, measured in spring, but later there was partial compensation for these losses. Grain number per ear and 1000 grain weight of individual tillers were reduced by severe eyespot infection; moderate infection reduced only 1000 grain weight; slight infection caused no reduction. Tillers without severe infection produced extra grains in severely diseased plots, so that there was no overall effect of eyespot on grain number per ear. The results are discussed in relation to the breeding of dwarf cultivars, which may be highly resistant to lodging but can nevertheless suffer severe losses from eyespot.

Impact of increasing temperature on the fitness of Fusarium pseudograminearum causing crown rot in wheat

“…Similar to other crop diseases such as eyespot caused by Cercosporella herpotrichoides on wheat (Scott & Hollins, 1974), increasing disease severity of crown rot was associated with a reduction in GW in this study. This is in agreement with the literature where it has been well reported that crown rot significantly reduces crop yields , Smiley et al, 2005.…”

“…Similar With respect to TN, at each of the four temperatures there was no statistical difference between the control and inoculated treatments indicating that disease did not influence this measure. Interestingly, TN has previously been reported to be reduced by a range of diseases, including in the presence of crown rot (Plummer et al, 1990, Scott & Hollins, 1974, Serafin & Simpfendorfer, 2010. Similar to the control plants however, the number of tillers produced for the inoculated samples tended to increase with warming.…”

How do eyespot resistance genes transferred into winter wheat breeding lines affect their yield?

“…Eyespot causes the reduction of nutrient transport at the stem base and lodging, which consequently, can lead to a significant yield reduction (Lucas et al 2000), even up to 50% (Murray 2010). Yield losses are due to the reduced number of tillers, premature wilting or death of stems, and smaller kernels (Scott and Hollins 1974;Murray and Bruehl 1986).…”

Using markers and field evaluation to identify the source of eyespot resistance genePch1in the collection of wheat breeding lines

“…Severe eyespot lesions can weaken stem bases and cause them to bend or break, which could result in yield losses of up to 50% (Fitt et al 1988;Janczewska 1991;Murray 2010). Eyespot also results in reduced tiller number, kernel number per head, and 1000-kernel weight (Scott and Hollins 1974;Murray and Bruehl 1983). Moreover, it is hypothesized that eyespot reduced yield of winter wheat in two ways: direct losses caused by eyespot lesions that interfered with movement of water and nutrients through the stems and indirect losses caused by lodging that interfered with harvest (Glynne 1944).…”