Search Results
Abstract
Correlation coefficients based on relative concentrations of 13 glucosinolates in the edible parts of 30 cultivars were determined. Brussels sprouts (Brassica oleracea L. gemmifera group), cauliflower (B. oleracea L. botrytis group), and either marrow-stem or smooth-leafed kale (B. oleracea L. acephala group) had similar glucosinolate patterns based on significant correlations (P < 0.01). The glucosinolates of ‘Morris Heading’ collards [(B. oleracea L. acephala group (var. sabellica)] were highly correlated with those of curly kale [B. oleracea L. acephala group (var. selensia)]. Mustard greens [B. juncea (L.) Czern. & Coss. var. rugosa Bailey] and the corresponding seeds were the most highly correlated of the 17 cultivars for which the edible parts and seeds were compared. Seed analyses indicated relationships among the cultivars somewhat similar to those seen for the edible portions.
Abstract
Fourteen cultivars of turnip [Brassica rapa, rapifera group, also B. campestris L. ssp. rapifera (Metzg.) Sinsk.] recommended for human consumption of either tops or tops and roots and five cultivars recommended for consumption of roots were selected to compare glucosinolate (GS) levels in tops and roots. Also, two cultivars used for animal feed were included. The study revealed significantly lower levels of 1-methylpropyl-GS and 2-hydroxy-3-butenyl-GS in tops and roots of cultivars grown for greens, compared to those used for animal feed. Contents of 1-methylpropyl-, 3-butenyl-, and 4-pentenyl-GSs were higher in turnip tops than in roots, while 2-hydroxy-3-butenyl-, 4-(methylthio)butyl-, 4-(methylsulfinyl)butyl-, 2-hydroxy-4-pentenyl-, 5-(methylthio)pentyl-, 2-phenylethyl-, 3-indolylmethyl-GSs and total GS were all higher in the roots. GS patterns for seeds tended to correlate with those of the tops.
Abstract
Seventy-nine cultivars and lines of cabbage Brassica oleracea L. (Capitata group) were analyzed for 11 glucosinolates to provide a data base of the levels of these potential toxicants. Aglucon hydrolytic products of glucosinolates from fresh cabbage (mean of 79 cultivars) include 24 ppm allyl isothiocyanate, 45 ppm 3-methylsulfinylpropyl isothiocyanate, 18 ppm SCN ion, 17 ppm 4-methylsulfinylbutyl isothiocyanate, and 4 ppm goitrin. Composition of the cultivars are summarized by type (red, white, savoy) and by end use (market, storage, kraut). Glucosinolates with a 3-carbon aglucon (excluding the sinolate carbon) predominate over 4-carbon glucosinolates in white and savoy types. Four-carbon glucosinolates (including goitrin precursor) predominate in red cabbages. Savoy cabbages are high in glucosinolates yielding SCN ion. Distinctions between market, storage, and kraut cultivars are less well defined. No differences could be seen between open pollinated and hybrid cultivars. Year-to-year variation for 12 cultivars is discussed.
High tunnels are becoming an increasingly important production tool for vegetable, small fruit, and cut flower growers in many parts of the United States. They provide a protected environment relative to the open field, allowing for earlier or later production of many crops, and they typically improve yield and quality as well as disease and pest management. Producers, ranging from small-scale market gardens to larger scale farms, are using high tunnels of various forms to produce for early markets, schedule production through extended seasons, grow specialty crops that require some environmental modification, and capture premium prices. The rapid ongoing adoption of high tunnels has resulted in numerous grower innovations and increased university research and extension programming to serve grower needs. An informal survey of extension specialists was conducted in 2007 to estimate numbers (area) of high tunnels and crops being grown in them by state, and to identify current research and extension efforts. Results of this survey provide an indication of the increasing importance of these structures for horticultural crop production across the country.
Production of european pears (Pyrus communis L.) in the eastern United States is limited by a number of physiological and pathological problems. In an attempt to expand sustainable pear production in that region, a series of long-term field trials of asian pear [Pyrus pyrifolia (Burm. F) Nak. (syn. Pyrus serotina L.)] were established at two sites in Maryland. To compare precocity, productivity, and survival, nine asian pear cultivars and three European cultivars were planted in a replicated trial in 2010 at the Wye Research and Education Center (Wye REC). The asian pears were precocious and productive and many trees flowered and fruited in the second leaf. After the fourth leaf, survival of ‘Isi’iwasi’, ‘Shinsui’, ‘Kosui’, and ‘Olympic’ was good, while many ‘Hosui’ and ‘Ya Li’ (asian pear) trees as well as ‘Bartlett’ and ‘Golden Russett’ (european pear) trees had died at that point, following bloom infections of fire blight (Erwinia amylovora). At Keedysville (WMREC), 18 asian pear cultivars in two established plantings were evaluated for their field tolerance to fire blight following a severe hailstorm. The cultivars Shin Li, Daisu Li, Shinsui, and Olympic fared as well as Magness, a fire blight–tolerant european pear cultivar that served as a benchmark in that evaluation. Conversely, ‘Hosui’, ‘Choju’, ‘Kosui’, ‘Seigyoku’, ‘Ya Li’, and ‘Ts’e Li’ were severely damaged. Three consumer tastings were conducted using fruit from the Wye REC trial. ‘Yoinashi’, ‘Atago’, ‘Shinko’, and ‘Olympic’ were well received by consumers. After tasting asian pears, most people, even those less familiar with the crop, reported they would consider purchasing the fruit and requested the names of local producers. Based on our long-term research results, there appears to be a good opportunity for locally produced asian pear fruit. With the correct cultivar selection for fire blight management, local growers should be able to produce this alternative crop sustainably and market their fruit profitably.
Recently, claims have been made that the use of glyphosate and transgenic crop traits increases plant susceptibility to pathogens. Transgenic traits used widely for years in dent corn are now available in commercial sweet corn cultivars, specifically, the combination of glyphosate resistance (GR) and Lepidoptera control (Bt). The objective was to assess the interactions of the GR+Bt trait, glyphosate, and Goss’s wilt on sweet corn. Nine treatments were tested under weed-free conditions at two sites in 2013 and 2014. Treatments included two isogenic cultivars differing only in the presence or absence of GR+Bt, with and without postemergence application of glyphosate, and inoculation with the causal agent of Goss’s wilt (Clavibacter michiganensis ssp. nebraskensis) before glyphosate application, after glyphosate application, or no inoculation. Results failed to show glyphosate or the GR+Bt trait influenced sweet corn susceptibility to Goss’s wilt. The only factor affecting Goss’s wilt incidence was whether plants were inoculated with C. michiganensis ssp. nebraskensis. In the absence of glyphosate application, yet under weed-free conditions, several yield traits were higher in sweet corn with the GR+Bt trait. Results showed that the GR transgene confers the same level of tolerance to glyphosate in sweet corn as observed previously in dent corn. If true, recent claims about glyphosate and transgenic traits increasing plant disease would be of major concern in sweet corn; however, no relationships were found between the GR+Bt trait and/or glyphosate to Goss’s wilt incidence in sweet corn.
Abstract
‘Priam’ is a new fall red apple with resistance to apple scab caused by Venturia inaequalis (Cke.) Wint. ripening close to ‘Jonathan’ and about one week before ‘Delicious’ (Fig. 1).
With increased mobile device usage, mobile applications (apps) are emerging as an extension medium, well suited to “place-less” knowledge transfer. Conceptualizing, designing, and developing an app can be a daunting process. This article summarizes the considerations and steps that must be taken to successfully develop an app and is based on the authors’ experience developing two horticulture apps, IPMPro and IPMLite. These apps provide information for major pests and plant care tasks and prompt users to take action on time-sensitive tasks with push notifications scheduled specifically for their location. Topics such as selecting between a web app and a native app, choosing the platform(s) for native apps, and designing the user interface are covered. Whether to charge to download the app or have free access, and navigating the intra- and interinstitutional agreements and programming contract are also discussed. Lastly, the nonprogramming costs such as creating, editing, and uploading content, as well as ongoing app management and updates are discussed.
Mobile device applications (apps) have the potential to become a mainstream delivery method, providing services, information, and tools to extension clientele. Testing, promoting, and launching an app are key components supporting the successful development of this new technology. This article summarizes the considerations and steps that must be taken to successfully test, promote, and launch an app and is based on the authors’ experience developing two horticulture apps, IPMPro and IPMLite. These apps provide information for major pests and plant care tasks and prompt users to take action on time-sensitive tasks with push notifications scheduled specifically for their location. App testing and evaluation is a continual process. Effective tactics for app testing and evaluation include garnering focus group input throughout app development and postlaunch, in-house testing with simulators, beta testing and the advantages of services that enhance information gained during beta testing, and postlaunch evaluations. Differences in promotional and bulk purchasing options available among the two main device platforms, Android and iOS, are explored as are general preparations for marketing the launch of a new app. Finally, navigating the app submission process is discussed. Creating an app is an involved process, but one that can be rewarding and lead to a unique portal for extension clientele to access information, assistance, and tools.