QUANTITATIVE TRAIT LOCI FOR AGRONOMIC AND END-USE QUALITY PERFORMANCE AND THE EFFECT OF SOILBORNE WHEAT MOSAIC VIRUS IN A HARD WINTER WHEAT POPULATION IN NEBRASKA

To better understand agronomic and end-use quality in wheat (Triticum aestivum L.) we developed a population containing 154 F6:8 recombinant inbred lines (RILs) from the cross TAM107-R7/Arlin. The parental lines and RILs were phenotyped at six environments in Nebraska and differed for resistance to Wheat soilborne mosaic virus (WSBMV), morphological, agronomic, and end-use quality traits. Additionally, a 2300 cM genome-wide linkage map was created for quantitative trait loci (QTL) analysis. Based on our results across multiple environments, the best RILs could be used for cultivar improvement. The population and marker data are publicly available for interested researchers for future research. The population was used to determine the effect of WSBMV on agronomic and end-use quality and for the mapping of a resistance locus. Results from two infected environments showed that all but two agronomic traits were significantly affected by the disease. Specifically, the disease reduced grain yield by 30% of susceptible RILs and they flowered 5 d later and were 11 cm shorter. End-use quality traits were not negatively affected but flour protein content was increased in susceptible RILs. The resistance locus SbmTmr1 mapped to 27.1 cM near marker wPt-5870 on chromosome 5DL using ELISA data. Finally, we investigated how WSBMV affected QTL detection in the population. QTLs were mapped at two WSBMV infected environments, four uninfected environments, and in the resistant and susceptible RIL subpopulations in the infected environments. Fifty-two significant (LOD≥3) QTLs were mapped in RILs at uninfected environments. Many of the QTLs were pleiotropic or closely linked at 6 chromosomal regions. Forty-seven QTLs were mapped in RILs at WSBMV infected environments. Comparisons between uninfected and infected environments identified 20 common QTLs and 21 environmentally specific QTLs. Finally, 24 QTLs were determined to be affected by WSBMV by comparing the subpopulations in QTL analyses within the same environment. The comparisons were statistically validated using marker by disease interactions. These results showed that QTLs can be affected by WSBMV and careful interpretation of QTL results is needed where biotic stresses are present. Finally, beneficial QTLs not affected by WSBMV or the environment are candidates for marker-assisted selection.

RP92-217 #2 Producer Marketing Mangement: Deferred Pricing Alternatives for Grain

Grain producers must make marketing decisions every day. First they must decide whether to price or hold grain. If they decide to price grain, they must then choose the most appropriate method of pricing: cash sale, forward contract, or hedging. If they decide to hold grain (not to price), they must choose the most appropriate method of retaining ownership. This fact sheet presents some guidelines to help producers choose the least costly method of owning grain or speculating on price level changes.

RP92-217 No. 19 Cost of Grain Storage

Grain marketing decisions are among the toughest the farm owner/operator or manager must make. Grain producers store grain to speculate on receiving higher prices, earn a return above storage costs, or to take advantage of government programs. Prices must increase enough to cover the additional costs, or forward contract prices must exceed current prices by more than the cost of storage in order to justify forward pricing. The gain in prices received can come from both changes in price level and changes in basis. This research publication discusses all the areas of the cost of grain storage.

Grain Storage Costs and Rental Rates

Trends in Grain Storage - Commercial grain storage eliminates the need to monitor grain conditions and, hence, offers the peace of mind that unsold grain will remain in condition. There may be a cost trade-off between this reduced storage risk and the cost of on-farm storage.