White sweet corn (Zea mays L.) is widely grown in the southeastern United States. Although `Silver Queen' has been a popular variety in that region for over 20 years, many other varieties are now available. Selecting a variety for commercial or home production is a complex decision because varieties vary considerably with regard to field performance, ear characteristics, and eating quality. Because limited information is available on overall evaluation of sweet corn varieties, the objectives of this study were to 1) evaluate field performance, ear characteristics and eating quality of selected white sweet corn varieties, 2) globally compare varieties using an overall rank-sum index (ORSI), and 3) determine if `Silver Queen' is still the best variety or if it benefits from name recognition. Significant differences among varieties were found for most of the attributes evaluated. When a variety needs to be selected on the basis of a single group of attributes, our results suggest that the best varieties for field performance, ear characteristics and eating quality were `Even Sweeter' and `Treasure', `Silver Queen' and `Rising Star', and `Silverado', respectively. When ranks for all attributes were pooled together, the ORSI for all varieties fell within the 40 to 60 median range for ORSI. These results suggest that while marked differences between varieties can be found for a selected attribute, overall all selected varieties showed similar potential for commercial production. Panel response on sweet corn variety names and the rate of correct blind identification of `Silver Queen' suggested that while it is still among the best varieties, `Silver Queen' did benefit from name recognition.

Conidia produced on overwintered lesions on 1-year-old twigs constitute the only source of primary inoculum for the peach scab fungus, Fusicladium carpophilum; however, there is little quantitative information about the dynamics of sporulation throughout the season. Starting in late winter and continuing until midsummer over a 4-year period, twig segments were sampled every 1 to 2 weeks from peach trees untreated with fungicide from a total of 18 trials (site–cultivar–year combinations) in Georgia, Alabama, and South Carolina. Twig samples were incubated in a moist chamber in the laboratory for 48 h and washed on a wrist-action shaker, and conidial production potential was determined by microscopic counts in aliquots of the wash water. When plotted against calendar date (day of the year), there was considerable variation among cultivars, sites, and years in the temporal pattern of conidial numbers of F. carpophilum. For example, conidia first were detected on samples collected between mid-February and late March, and the highest peak in conidial numbers was observed between late March and mid-May. In contrast, when conidial numbers were expressed as cumulative totals in relation to phenological time (either days after full bloom or days after calyx-split), temporal progress was very similar among trials. Conidial production summarized in this manner generally commenced before bloom and reached 25 and 90% of the seasonal total by calyx-split and 10 weeks after bloom, respectively. A two-parameter sigmoidal function described the relationship between cumulative conidial production and phenological time very well (R2 = 0.9727 and 0.9790 for days after full bloom and days after calyx-split, respectively; P < 0.0001, n = 260). Expression of time in degree-days did not improve the relationship between cumulative conidial numbers and phenological time. Thus, knowledge of host tree phenology may be sufficient to derive strategic estimates of disease risk based on the predictable seasonal pattern of conidial production potential; this seasonal, inoculum-based risk estimate may be used to adjust daily infection risk estimates based on models that consider microclimatic conditions affecting pathogen growth and infection.

Effects of Tergitol-TMN-6 surfactant on blossom thinning (fruit set), fruit quality, and yield were studied in different cultivars of peach (Prunus persica [L.] Batsch) during 2003 to 2005, and in one cultivar of nectarine Prunus persica [L.] in one orchard and one cultivar of plum (Prunus domestica [L.]) in two orchards in 2004. In addition to Tergitol-TMN-6, effects of Crocker's fish oil (CFO) alone in three peach cultivars or in combination with lime sulfur in a nectarine cultivar were studied on fruit set, quality, and yield. Tergitol-TMN-6 at 5 mL·L–1 or higher rates, applied at about 75% to 85% bloom, reduced fruit set without russeting peach fruit. Peach fruit size was often increased by Tergitol-TMN-6 treatment. Applications of Tergitol at 20 mL·L–1 or 30 mL·L–1 excessively thinned peaches. Tergitol-TMN-6 at all rates burned foliage, but the symptoms disappeared after a few weeks without any adverse effects on tree productivity. Tergitol-TMN-6 at 7.5 mL·L–1 or 10 mL·L–1, applied either once at about 80% to 85% bloom or twice at 35% bloom and again at 80% to 85% bloom, reduced fruit set without any fruit russeting in nectarine. Tergitol-TMN-6 at 7.5 mL·L–1 to 12.5 mL·L–1 reduced fruit set in `Empress' plum. CFO at 30 mL·L–1 was effective in blossom thinning of some peach cultivars. A combination of lime sulfur and CFO was not effective in blossom thinning of nectarine. Considering results from several orchards in different locations in the Pacific Northwest over 3 years, Tergitol-TMN-6 is an excellent blossom thinner for peach, nectarine, and plum at rates of 7.5 to 12.5 mL·L–1, sprayed at a spray volume of 1870.8 L·ha–1 when about 75% to 85% blooms are open.

All the TIS programs evaluated provided effective control of PC and represent potential alternatives to the conventional weekly spray program in peaches with concomitant reduction in insecticide usage and associated costs. However, an additional spray may be necessary for effective control of PC and stink bugs in late-season peach varieties.

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