Bacterial wilt, caused by Curtobacterium flaccumfaciens pv. flaccumfaciens, was first recognized and described as a new dry bean disease near Redfield, SD after the 1921 growing season on the farm of the Office of Forage Investigations. Between the late 1930s and the early 1950s it became one of the more problematic bacterial diseases of dry beans. It became an endemic problem in dry bean production throughout western Nebraska and other areas of the central high plains during the 1960s and early 1970s. By the early 1980s, the disease had virtually disappeared with the implementation of cultural practices. The disease was rediscovered in two fields in Nebraska late in the 2003 season. It was assumed to be an isolated incident. However, the next season the pathogen was widespread throughout western Nebraska production fields. Our research suggests that the return of bean wilt throughout the central high plains over the last decade is not due to a single factor but a combination of new changes in cultural practices, environmental stresses, and unfamiliarity with the pathogen and its past history.

Dry bean (Phaseolus vulgaris L.) is highly susceptible to drought stress, and drought affects 60% of global bean production. We evaluated elite exotic dry bean germplasm derived from the Mesoamerican gene pool for drought tolerance, yield, and adaptation to western Nebraska during 2006 and 2007 at three research sites. Seven tropical lines were evaluated with two great northern cultivars (Matterhorn and Beryl‐R) and one pinto cultivar (Bill‐Z) serving as checks. Adjacent nonstressed (NS) and drought‐stressed (DS) blocks were evaluated. Within each block, the selected lines were assigned to experimental units using a randomized complete block design with four replications at each location. On average, yield was 60% less, 100‐seed weight was 19.2% lower, and maturity occurred 4 d earlier under DS than under NS conditions. Beryl‐R, SER 22, and Matterhorn had the greatest average yield under both NS (3564, 3347, and 3440 kg ha−1, respectively) and DS (1701, 1773, and 1584 kg ha−1, respectively). These genotypes were also the most drought tolerant based on the drought susceptibility index (0.9, 0.8, and 0.9, respectively) and geometric mean (2462, 2436, and 2335, respectively). Based on these results, Matterhorn, Beryl‐R, and SER 22 show the most promise for use in breeding for drought tolerance.

Field trials were conducted in 1999 and 2000 to determine the influence of weed size and the number of glyphosate or glufosinate applications on weed control and sugarbeet yield. Glyphosate at 840 g/ha or glufosinate at 390 g/ha was applied one, two, or three times, beginning when the average weed height was 3, 10, 15, or 25 cm. Two sequential applications of glyphosate applied to 10-cm weeds or three sequential applications of glufosinate applied to 3-cm weeds provided weed control comparable to three sequential applications of desmedipham plus phenmedipham plus triflusulfuron plus clopyralid. Weed control and sugarbeet root yield were optimal for two postemergence applications of glyphosate and for three applications of glufosinate. Glyphosate provided greater control of redroot pigweed and common lambsquarters than glufosinate. Sugarbeet sucrose yield with both glyphosate and glufosinate weed control programs was nearly 10,000 kg/ha. Compared with two sequential applications of glyphosate, sucrose yield of glyphosate-resistant sugarbeet was reduced 15% by three sequential applications of desmedipham plus phenmedipham plus triflusulfuron plus clopyralid. Sucrose yields were similar between three sequential applications of glufosinate and three applications of desmedipham plus phenmedipham plus triflusulfuron plus clopyralid.

Chicory (Cichorium intybus L.) is not extensively grown in the USA for fructan production, and there is limited information available on the effect of cultural practices on root yield. Three field experiments were conducted from 1995 through 2002 to determine the influence of planting and harvest date and cultivar on yield and carbohydrate composition of chicory roots. Different chicory cultivars were planted from the first of April through mid‐May and were monitored for plant stand, leaf area, and bolting during the growing season and for root yield in late summer, fall, and the following spring. Roots were characterized for carbohydrate composition with high performance anion exchange chromatography. Plant stands and root yields were similar when chicory was planted in early and mid‐April, but root yields declined 35% when planting date was delayed until mid‐May. Harvest date was closely associated with root yield and total sugar content. Root yields increased 84% from 1 September to 15 November. Total sugar content was 197 mg g−1 fresh weight when roots were harvested in early November. The degree of fructan polymerization (DP) was also influenced by harvest date. The percentage of longer chain‐length fructans increased until the first fall frost (−3°C). Forty‐five days following the first frost, the percentage of longer chain‐length fructans in the DP > 20 category declined from 23 to 13% of the total carbohydrate, and the percentage of shorter chain‐length fructans in the DP 3 to 10 category increased from 36 to 45% of the total carbohydrate. Chicory stand, leaf area, bolting percentage, root yield, total sugar content, and degree of fructan polymerization were influenced by cultivar selection. Results from 7 yr of research indicated that chicory could be successfully grown in western Nebraska.

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