adoption of biological control by end users. Quality assessment of any biological control agent, whether it be a parasitoid, predator, or pathogen, is important; however, no government agency regulates the quality of commercially produced natural enemies
Erick X. Caamano, Raymond A. Cloyd, Leellen F. Solter, and Declan J. Fallon
Valtcho D. Zheljazkov, Charles L. Cantrell, M. Wayne Ebelhar, Christine Coker, and William B. Evans
Baikal skullcap (Scutellaria baicalensis) is an important medicinal plant with proven bioactivity. Commercially available products in the United States containing extracts or derivatives from this plant species have been shown to lack consistency of chemical composition and bioactivity. In the United States, these issues could be solved through domestic production of skullcap. The hypothesis of this study was that Baikal skullcap grown in the Mississippi climate would accumulate sufficient bioactive flavonoids, baicalin, and baicalein in the roots to justify domestic production, and that shoots of these plants might also contain the flavonoids of interest. A replicated field experiment was conducted at four locations in Mississippi (Beaumont, Crystal Springs, Stoneville, and Verona) to test the hypothesis. The concentration of the main flavonoid, baicalin, in the roots ranged from 8.1% to 15.6%, whereas the concentration of baicalein varied from 0.2% to 1.2%. The flavonoid concentrations in the roots were similar to that of commercially available skullcap roots, and to concentrations reported in the literature. Chrysin was detected in the roots from one location. Furthermore, the flavonoids apigenin, baicalein, baicalin, chrysin, and scutellarein were detected and quantified in the skullcap shoots. Overall, yields of dry roots tended to increase from southern to northern locations. This is the first report on flavonoid accumulation in Baikal skullcap roots and shoots grown in the United States. The results from this study are promising and suggest that 1) Baikal skullcap grown in Mississippi accumulates similar amounts of baicalein and baicalin to skullcap grown in other regions and can provide up to 128 kg·ha − 1 of baicalin and up to 2.32 kg·ha− 1 of baicalein; 2) flavonoid concentration in Baikal skullcap roots and shoots, yields, and mineral concentration of roots might depend on climatic and growing conditions; and 3) Baikal skullcap could be developed as a high-value crop for Mississippi and possibly other regions of the United States. Further research is needed on skullcap production methods and economic feasibility.
Angeline M. Peters and Aart van Amerongen
In this pilot study, we investigated the relationship between levels of bitter sesquiterpene lactones and sensory evaluation of chicory (Cichorium intybus L.). The levels of two bitter sesquiterpene lactones—lactucopicrin and lactucin-like sesquiterpene lactones—were measured by ELISA in raw and cooked chicory samples from several cultivars. Data were compared with the results of a sensory evaluation on the flavor attributes bitterness, typical chicory flavor, and total flavor intensity of identical chicory samples. Linear regression analysis demonstrated that the levels of lactucin-like sesquiterpene lactones were significantly related to bitterness (P = 0.006) and total flavor intensity (P = 0.03) attributes in raw chicory samples. When cooked chicory samples were evaluated, the levels of lactucin-like sesquiterpene lactones were significantly related to bitterness (P = 0.002), typical chicory flavor (P < 0.001), and total flavor intensity (P = 0.009) attributes, while lactucopicrin levels were related to bitterness (P = 0.002) only. These results show that the ELISA can be useful to predict flavor attributes in chicory.
Annette Wszelaki and Matthew D. Kleinhenz
This is the second of two related reports dealing with the effects of cultivar × environment interactions on cabbage (Brassica oleracea L., Capitata Group) crop traits. This study examined planting date and cultivar effects on physical head traits of processing cabbage and compared these findings to those from a similar study of fresh market cabbage. Six cultivars of processing cabbage were planted in May and June-July of 1999 and 2000 at the OARDC Vegetable Crops Research Branch in Fremont, Ohio. Marketable yield for each crop was determined, and measurements were taken of head weight, diameter, density, and volume, and core length, base width, and volume on more than 450 individual heads. Head and core volume and head density were calculated from these direct measures. Year, planting date, and cultivar significantly affected the majority of head traits. May planting led to higher marketable yield and heavier heads with larger diameters than June-July planting. The most variable trait across cultivars was head volume, which was affected by planting date in all cultivars. Differences between processing and fresh market cabbage were found. Average head polar/equatorial diameter values were affected by planting date in the fresh market but not the processing study. In contrast, head density and core volume as a percent of head volume were affected by planting date in the processing but not the fresh market study.
Zachary Stansell, Thomas Björkman, Sandra Branham, David Couillard, and Mark W. Farnham
high validity. Because horticultural quality assessments of broccoli heads are partially subjective, we also wanted to determine if a useful evaluation index based on greater human consensus could be constructed. In addition, it was recognized early
undergraduates to scientific methodology. Rather, the purpose was to give students an overview of pollen quality assessment, give students an idea of how real-world scientists test for this, show how to conduct a preliminary experiment, and to increase student
Penelope F. Measham, Audrey G. Quentin, and Nicholas MacNair
the laboratory for quality assessment: weight, diameter, color, and fruit flesh firmness. A subsample of 25 blemish-free fruit was assessed from each replicate tree. Fruit diameter at the widest point and fruit height were measured using digital
Monika Schreiner, Angelika Krumbein, Ilona Schonhof, Stefanie Widell, and Susanne Huyskens-Keil
A new approach for nondestructive quality assessment based on color measurement was developed for red radishes (Raphanus sativus L.). Postharvest changes in hue angle corresponded with changes in soluble and insoluble pectic substances linked to textural characteristics in `Nevadar' radishes. Changes in glucosinolates were related to changes in chroma and were associated with radish flavor. However, monosaccharides were not related to root color during the 4 days of postharvest period. Nevertheless, the data suggest that root color may be used as a rapid, inexpensive and reliable indicator of quality during the postharvest distribution of radish.
Mary Lamberts, Stephen K. O'Hair, Juan Carranza, George Hochmuth, and Edward Hanlon
Trials to determine crop nutrients for four vegetable crops grown on the limestone soils of Dade County, Fla., have been conducted in growers' fields to duplicate commercial growing conditions. This has increased grower participation in the experimental process. The four vegetable crops are snap beans, Irish potatoes, sweet corn, and malanga (a.k.a. yautia or tannia, Xanthosoma sagittifolium Schott). The discussion will focus on grower participation in various critical decision-making activities: a) location of plots in a commercial field, b) placement of fertilizers, c) possible problems with Restricted Entry Intervals, d) harvest determinations, and e) grading criteria and quality assessment.
Molla Md. Nuruddin, Chandra A. Madramootoo, and Georges T. Dodds
, professor of Vegetable Crops, Cornell Univ. We acknowledge the financial support of the International Council for Canadian Studies to M. Nuruddin. We thank R. Smith, greenhouse manager and E. Noroozi for help with fruit quality assessments.