No abstract

Most bell peppers (Capsicum annuum L.) produced and consumed are green. However, yellow, red, orange, white, black, and purple bell peppers are also available. While bell pepper consumption in the United States has been increasing in the past 10 years, limited information is available on how their color, retail price, and vitamin C content influence consumer preferences. A conjoint analysis of 435 consumer responses showed that, for the total sample, color was about three times more important than retail price in shaping consumers' purchase decisions, while vitamin C content was nearly irrelevant. Six distinct consumer segments were identified through cluster analysis. Four segments favored green peppers, while one segment favored yellow and one favored brown. Demographic variables generally were not good predictors of segment membership, but several behavioral variables, such as past bell pepper purchases, were significantly related to segment membership. While green is generally the preferred color, market segments exist for orange, red, yellow, and even brown peppers. Applications to marketing strategies suggested that price sensitivity could explain why green peppers were priced individually, but those of other colors were priced by weight, and that promotion of increased vitamin C content would be most effective if associated specifically with yellow and orange peppers.

Integrating hydroponic and aquaculture systems (aquaponics) requires balanced pH for plants, fish, and nitrifying bacteria. Nitrification prevents accumulation of fish waste ammonia by converting it to NO3 –-N. The difference in optimum pH for hydroponic cucumber (Cucumis sativa) (5.5 to 6.0) and nitrification (7.5 to 9.0) requires reconciliation to improve systems integration and sustainability. The purpose of this investigation was to: 1) determine the ammonia biofiltration rate of a perlite trickling biofilter/root growth medium in an aquaponic system, 2) predict the relative contribution of nitrifiers and plants to ammonia biofiltration, and 3) establish the reconciling pH for ammonia biofiltration and cucumber yield in recirculating aquaponics. The biofiltration rate of total ammonia nitrogen (TAN) removal was 19, 31, and 80 g·m−3·d−1 for aquaponic systems [cucumber, tilapia (Oreochromis niloticus), and nitrifying bacteria (Nitrosomonas sp. + Nitrobacter sp.)] with operating pH at 6.0, 7.0, and 8.0, respectively. With the existing aquaponic design (four plants/20 L perlite biofilter/100 L tank water), the aquaponic biofilter (with plants and nitrifiers) was three times more effective at removing TAN compared with plant uptake alone at pH 6.0. Most probable number of Nitrosomonas sp. bacteria cells sampled from biofilter cores indicated that the aquaculture control (pH 7.0) had a significantly higher (0.01% level) bacteria cell number compared with treatments containing plants in the biofilter (pH 6.0, 7.0, or 8.0). However, the highest TAN removal was with aquaponic production at pH 8.0. Thus, operating pH was more important than nitrifying bacteria population in determining the rate of ammonia biofiltration. Early marketable cucumber fruit yield decreased linearly from 1.5 to 0.7 kg/plant as pH increased from 6.0 to 8.0, but total marketable yield was not different. The reconciling pH for this system was pH 8.0, except during production for early-season cucumber market windows in which pH 7.0 would be recommended.

No abstract

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.