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As part of a study dealing with the influence of some environmental conditions on plant growth, water withdrawal patterns of Red Cabbage (Brassica oleracea L., c.v. Rode Herfst) grown on a sticky clay soil are analyzed. An analysis of the transport resistance for liquid flow in the plant as well as an investigation on the geometry factor of the root system for red cabbage is presented. The variation of these factors with depth is described, and root extraction rates at different depths are calculated and compared with data obtained from water balance studies. The plant resistance data are in reasonable agreement with existing literature. Because of a non-homogeneous and poor root development in the early stages of growth, the geometry data of the initial growing stages differ a factor ten from data found in literature. With root development increasing with depth, geometry data decrease to values also reported for other crops. From calculations it is shown that at increasing drying out of the soil the geometry factor is slightly affected, but the plant resistance increases considerably. The latter resistance, however, decreases when the evaporation flux from the plant increases. This phenomenon is mainly caused by the root distribution in the soil with depth, resulting in a relatively higher water uptake from the top layers, as compared with the deeper layers, when the evaporation flux increases. The obtained results may at least partly explain the apparent non-Darcian behaviour of the flux of water through the plants, sometimes reported in literature.

The relative resistance to insect attack of 43 varieties of Cruciferae representing 11 different Brassica crops, including 16 green and 5 red varieties of cabbage, were studied in field experiments conducted at Kenosha, Wisconsin, in 1960. Evaluations were made of the relative insect resistance of the various varieties to the cabbage maggot, Hylemya brassicae (Bouche); the imported cabbageworm, Pieris rapae (L.); the diamondback moth, Plutella maculipennis (Curtis); and the cabbage looper, Trichoplusia ni (Hubner). In the varieties screened, a considerable range of relative resistance was observed for each of the insect species studied. With few exceptions the relative level of resistance was found to be primarily a characteristic of the crop species and secondarily one of variety. The relative resistance of the different varieties to each of the insects was independent of the level of resitance to any other species; the mechanisms of resistance being different for each insect considered. Host selection could not be correlated with plant size for any of the insect pecies studies. In the cabbage varieties host selection by the imported cabbageworm was found to be related to foliage color; the red cabbage varieties being less susceptible to oviposition than any of the green varieties. Larval survival of this species was, however, favored on the red cabbage varieties, the larva/egg ratios being higher on these varieties than on the green cabbages.

Research has been carried out on clubroot resistant white cabbage received from Germany and the U.S.A. In the Netherlands, too, a number of plants of both origins were not affected. The European material proved more resistant than the American. In various respects these varieties do not come up to the requirements of growers in different parts of the world. The resistance will have to be bred into the established commercial varieties by repeated backcrosses. Resistance was found in some varieties of kale and Savoy cabbage, not in red cabbage, cauliflower, green sprouting broccoli and Brussels sprouts.

Throughout the 1961 growing season at Kenosha, Wis., frequent evaluations were made of the relative resistance of 8 commercial cabbage varieties to oviposition and larval attack by the imported cabbageworm, Pieris rapae (L.), and the cabbage looper, Trichoplusia ni (Hubner) ; to larvae of the diamondback moth, Plutella maculipennis (Curtis) ; and to injury by the cabbage aphid, Brevicoryne brassicae (L.); Seasonal shifts were observed in the relative resistance of the varieties to the imported cabbageworm, the diamondback moth, and the cabbage aphid, but no significant shifts were found in relative resistance to the cabbage looper, which does not occur in appreciable numbers until the latter part of the season. The red cabbage varieties proved least susceptible to early-season oviposition by the imported cabbageworm and to host selection by the alate cabbage aphid, but their susceptibility to both these species increased as the season progressed; the red varieties apparently are more favorable hosts for both these insects than are the green varieties. The varieties least injured by first-generation populations of the imported cabbageworm tended to be relatively more susceptible to second-generation oviposition. Diamondback moth populations always were low, but varietal preferences became more pronounced as the season advanced. Two green varieties showed significant shifts in resistance to this species.

Summary The reaction with O 8 O 4 was used to localize anthocyanins by means of the electron microscope. Precipitates were observed within the vacuoles of anthocyanin-containing cortical cells of red cabbage hypocotyl. No evidence was found for the existence of organelles in these vacuoles. Only large, strongly osmiophilic globules free of surrounding membranes and internal structures were observed inside the vacuoles. The nature of these inclusions is still unknown.

Eight anthocyanins were isolated from illuminated red cabbage seedlings. They were identified as: cyanidin-3-sophoroside-5-glucoside, cyanidin-3-malonyl-sophoroside-5-glucoside, cyanidin-3-p-coumaryl-sophoroside-5-glucoside, cyanidin-3-(di-p-coumaryl)sophoroside-5-glucoside, cyanidin-3-ferulyl-sophoroside-5-glucoside, cyanidin-3-(diferulyl)sophoroside-5-glucoside, cyanidin-3-sinapylsophoroside-5-glucoside, and cyanidin-3-(disinapyl)-sophoroside-5-glucoside.

In experiments in which spectrophotometric reflectance patterns of real leaves were mimicked with mixtures of artists' pigments, leaf color was shown to be a character used by cabbage root flies, before landing on leaves, to discriminate among the host plant cultivars radish, green cabbage, and red cabbage. It may be possible to take advantage of factors that affect leaf color, such as epicuticular bloom, pubescence, and masking of chlorophyll by other pigments, to decrease the attraction of certain pest insects to plants.

The promotion of anthocyanin synthesis in red-cabbage seedlings by 5 min exposure to R light is inhibited by subsequent application of CaCl 2 . The stimulation of dark synthesis of anthocyanin by n -PrOH and by kinetin is also reduced by Ca 2+ and by cholesterol, both of which are well known to stabilize cell membranes. By contrast, EDTA, which chelates Ca 2+ , promotes dark synthesis of anthocyanin. Assay of native Ca 2+ extractable from seedlings immersed in EDTA demonstrates that R light exposure promotes a highly significant increase in extractable Ca 2+ . It is suggested that the molecular configuration of the phytochrome molecule affects the ability of a membrane to bind Ca 2+ and that this in turn affects the permeability to substrates which are required for anthocyanin biosynthesis.

A study of the ultrastructure of anthocyanoplasts from the seedling hypocotyl and leaves from the heart of red-cabbage plants has been made. Evidence is presented that the anthocyanoplast does not represent a hydrophobic droplet but is bounded by a single tripartite membrane approximately 10 nm in thickness. The results provide further support for the view that the anthocyanoplast is an intracellular compartment containing at least the later enzymes of anthocyanin biosynthesis, which are thereby separated from the hostile acidic environment of the vacuolar sap.

The soluble sugar contents of 17 raw and cooked vegetables were determined by TLC and HPLC. In general, the soluble carbohydrate content of vegetables is low. For raw materials the highest content was found in carrot, red cabbage, egg plant, green bean and leek. Upon cooking the glucose, fructose and total sugar contents decrease and this diminution is more drastic in the case of frying. The amount of sucrose, except in the case of carrot, egg plant and green bean, increases with cooking. The maltose content of the broad bean increases in the culinary process.

In confirmation of Maximov's earlier results, non-penetrating (sucrose) and penetrating (dimethylsulfoxide) substances lowered the frost killing temperature from -6°C in the control to -11° to -24°C, depending on the concentration. In contrast to his results, neither glycerol nor CaCl2 provided as good or as consistent protection. The addition of 0.05 M mercaptoethanol overcame this protective effect either completely (low concentrations of protectant) or partially (high concentrations). The effect of the mercaptoethanol occurs during freezing and not during thawing. Since ethanol, without the mercapto-(SH) group, does not counteract the protective effect, such protection must be related in some way to the sulfhydryl group — perhaps by an effect on the disulfide and sulfhydryl groups of the proteins.

Ethylene control of anthocyanin formation functions only through light-initiated synthesis pathways of the rapid synthesis phase. Treatment with ethylene in the dark had no effect on dark anthocyanin synthesis in red cabbage (Brassica oleracea L.). Pretreatment of both red cabbage and sorghum (Sorghum vulgare L.) with ethylene for 24 hours in the dark did increase the rate of synthesis when the tissue was placed in the light. Light-initiated anthocyanin synthesis is inhibited by ethylene when the tissue is returned to the dark.

This report presents the results of the 1975 vegetable variety trials conducted. Cultivars evaluated included broccoli, brussels sprouts, cabbage, red cabbage, savoy cabbage, cauliflower, and processing peppers.

Both enantiomers of α-aminooxy-β-phenylpropionic acid (AOPP), potent inhibitors of L-phenylalanine ammonia-lyase, and their N-benzyloxycarbonyl (N-BOC) derivatives inhibit anthocyanin formation in developing flowers of Ipomoea tricolor Cav. and Catharanthus roseus Don. as well as in seedlings of Brassica oleracea var. caulo-rapa DC (kohlrabi) and B. oleracea var. capitata L. (red cabbage) with little interference with their normal development. Kohlrabi seedlings tolerate up to 0.3 mM L-AOPP and N-BOC-L-AOPP without a reduction of fresh weight or chlorophyll content, while anthocyanin is reduced to less than 20%.

Summary of the variety trials conducted at the Muck Research Station in 1976.

Microscopic observations made during preparation of protoplasts and vacuoles from red radish seedling hypocotyl (Raphanus sativus L.) show that anthocyanoplasts, the strongly pigmented bodies present in the pigmented cells of the hypodermis, begin as apparently membranous vesicles in the cytoplasm made visible by the deposition and accumulation of anthocyanins, but only rarely appear in the isolated vacuole. Isolation of protoplasts and vacuoles was also achieved from mung bean seedling hypocotyl (Vigna radiata L Wilczek), red cabbage leaf (Brassica oleracea L.) and Prunus x yedoensis Matsum callus. Anthocyanoplasts were usually in the vacuole, although sometimes in the cytoplasm, of the mung bean and cabbage, but were never seen in vacuoles of Prunus callus.

A total of 18 vegetables: bell pepper (red and green); pepper (red and green), sallow thorn (Hyppophae rhammnoides) celery (leaves and root), cabbage (white, red, curly and Bruxelles), broccoli, cauliflower, radish, dill (leaves), parsley (leaves and roots); carrots were analyzed for antioxidant activities using FRAP method, DPPH method, total polyphenols content by Folin Ciocalteu method and ascorbic acid content using 2,6-dichlorophenol indophenols. The highest TAC values was identified for sallow thorn (Hyppophae rhammnoides), red cabbage, red bell pepper and pepper.

Red cabbage (RC) and purple sweet potato (PSP) are naturally rich in acylated cyanidin glycosides that can bind metal ions and develop intramolecular π-stacking interactions between the cyanidin chromophore and the phenolic acyl residues. In this work, a large set of RC and PSP anthocyanins was investigated for its coloring properties in the presence of iron and aluminum ions. Although relatively modest, the structural differences between RC and PSP anthocyanins, i.e., the acylation site at the external glucose of the sophorosyl moiety (C2-OH for RC vs. C6-OH for PSP) and the presence of coordinating acyl groups (caffeoyl) in PSP anthocyanins only, made a large difference in the color expressed by their metal complexes. For instance, the Al3+-induced bathochromic shifts for RC anthocyanins reached ca. 50 nm at pH 6 and pH 7, vs. at best ca. 20 nm for PSP anthocyanins. With Fe2+ (quickly oxidized to Fe3+ in the complexes), the bathochromic shifts for RC anthocyanins were higher, i.e., up to ca. 90 nm at pH 7 and 110 nm at pH 5.7. A kinetic analysis at different metal/ligand molar ratios combined with an investigation by high-resolution mass spectrometry suggested the formation of metal–anthocyanin complexes of 1:1, 1:2, and 1:3 stoichiometries. Contrary to predictions based on steric hindrance, acylation by noncoordinating acyl residues favored metal binding and resulted in complexes having much higher molar absorption coefficients. Moreover, the competition between metal binding and water addition to the free ligands (leading to colorless forms) was less severe, although very dependent on the acylation site(s). Overall, anthocyanins from purple sweet potato, and even more from red cabbage, have a strong potential for development as food colorants expressing red to blue hues depending on pH and metal ion.

A total of 132 Rhizoctonia isolates were recovered from red cabbage plants with root rot and wirestem symptoms in the province of Samsun (Turkey) between 2018 and 2019. Based on the sequence analysis of the internal transcribed spacer (ITS) region located between the 18S and 28S ribosomal RNA genes and including nuclear staining, these 124 isolates were assigned to multinucleate Rhizoctonia solani, and eight were binucleate Rhizoctonia. The most prevalent anastomosis group (AG) was AG 4 (84%), which was subdivided into AG 4 HG-I (81%) and AG 4 HG-III (3%), followed by AG 5 (10%) and AG-A (6%), respectively. The unweighted pair group method phylogenetic tree resulting from the data of 68 isolates with the inter-PBS amplification DNA profiling method based on interspersed retrotransposon element sequences confirmed the differentiation of AGs with a higher resolution. In the greenhouse experiment with representative isolates (n = 24) from AGs on red cabbage (cv. Rondale), the disease severity index was between 3.33 and 4.0 for multinucleate AG isolates and ranged from 2.5 to 3.17 for AG-A isolates. In the pathogenicity assay of six red cabbage cultivars, one isolate for each AG was tested using a similar method, and all cultivars were susceptible to AG 4 HG-I and AG 4 HG-III isolates. Redriver and Remale were moderately susceptible, while Rescue, Travero, Integro, and Rondale were susceptible to the AG 5 isolate. The results indicate that the most prevalent and aggressive AGs of Rhizoctonia are devastating pathogens to red cabbage, which means that rotation with nonhost-crops for these AGs may be the most effective control strategy. This is the first comprehensive study of Rhizoctonia isolates in red cabbage using a molecular approach to assess genetic diversity using iPBS-amplified DNA profiling.

SECONDARY products of plant metabolism, such as alkaloids, essential oils, anthocyanins, etc., have been generally looked upon as being definitely eliminated from any further metabolic processes in the plant. Investigations that are now being made with the view of ascertaining the genesis of anthocyanins have led to results that prove the contrary. If, for example, seeds of red radishes (Raphanus sativus), or red cabbage (Brassica oleracea capitata rubra), are left to germinate on sand, anthocyanins will show as early as the first few days following germination, at first in the cotyledons, and later on in the hypocotyls. Now, if those seedlings are subjected to etiolation, their anthocyanins, affected by the metabolic process of etiolation, will disappear. This will be seen with both cool (50° F.) and warm (95° F.) temperatures. The resorption of anthocyanins will take a few days only, at 95° F., whereas at 50° F. the resorption takes several weeks to be completed.

There are several theories on photoaging and its etiology. At this time, however, the only defenses commonly believed to prevent photoaging are the use of sunscreens to reduce the amount of ultraviolet (UV) that reaches the skin, the use of retinoids to prevent production of collagenase and stimulate collagen production, and the use of antioxidants to reduce and neutralize free radicals. The Pinnell paper in this issue of the Journal of Investigative Dermatology that examines ferulic acid combined with vitamins C and E shows that this formulation seems to provide two of the above defenses: a sunscreen effect, and an antioxidant effect. Not all sunscreens confer an antioxidant effect and not all antioxidants yield a sunscreen effect (Pinnell et al, 2005b). For example, Kang et al (2003) showed that although genistein and Nacetyl cysteine exhibit antioxidant activity, they produced no effect on ultraviolet-induced erythema. UV exposure results in skin damage through several mechanisms including sunburn cell development, thymine dimer formation, collagenase production, and the provocation of an inflammatory response. Sunburn cells, or UV-induced apoptotic cells, have long been used to assess skin damage due to ultraviolet exposure. UV-induced apoptosis is mediated by caspase-3 (Lin et al, 2005). Activation occurs in a pathway that involves caspase-7 (Pinnell et al, 2005a). It is believed that capsase-3 levels are good indicators of the presence of cellular apotosis (Kang et al, 2003; Philips et al, 2003; Lin et al, 2005; Yao et al, 2005). Theoretically, the fewer sunburn cells present, less the ‘‘skin damage’’ from UV exposure. At this time, sun avoidance and use of sunscreens are the only defenses against sunburn cell formation. Sunscreens and sun avoidance can also protect against thymine dimer formation. Antioxidants protect the skin from free radicals through several mechanisms in the early stages of elucidation. Free radicals can act directly on growth factors and cytokine receptors in keratinocytes and dermal cells, leading to skin inflammation. Kang et al have shown that free radical activation of the mitogen-activated protein (MAP) kinase pathways results in production of collagenase, which leads to degradation of collagen (Saliou et al, 2001; Greul et al, 2002; Kang et al, 2003; Papucci et al, 2003; Passi et al, 2003; Middelkamp-Hup et al, 2004a, b; Sime and Reeve, 2004; Katiyar, 2005). Blocking these pathways with antioxidants is thought to prevent photoaging by preventing the production of collagenase. This theory has been buttressed by research on human skin performed by Kang et al. In this study, investigators showed that when human skin was pretreated with the antioxidants genistein and N-acetyl cysteine, the UV induction of the cJun-driven enzyme collagenase was inhibited. Many antioxidants are now available in oral and topical preparations. Studies such as the one by Pinnell suggest that combinations of various antioxidants may have synergistic effects, yielding formulations with greater efficacy than any of the individual antioxidant compounds used alone. Each antioxidant is endowed with various properties that distinguish it from other antioxidants. Some examples of popular antioxidants and their characteristics will be briefly discussed. Pycnogenol is a trademark name for a standardized extract of the bark of the French maritime pine plant, which is rich in procyanidins, also called proanthocyanidins. These potent free-radical scavengers can also be found in grape seed, grape skin, bilberry, cranberry, black currant, green tea, black tea, blueberry, blackberry, strawberry, black cherry, red wine, and red cabbage. In one study (Sime and Reeve, 2004), Pycnogenol concentrations of 0.05%– 0.2% were applied to the irradiated dorsal skin of Skh:hr hairless mice exposed daily to minimally inflammatory solarsimulated UV radiation. Mice pretreated with Pycnogenol demonstrated a concentration-dependent reduction of the inflammatory sunburn reaction (edema). In a study (Saliou et al, 2001) evaluating the capacity of pine bark extract to protect human skin against erythema induced by solar radiation, 21 volunteers received oral supplementation of Pycnogenol. During supplementation, the UVR level necessary to reach one minimal erythema dose (MED) was significantly elevated, suggesting that oral pine bark extract supplementation mitigates the effects of UV radiation on the skin, lowering erythema. The mechanism of action of Pycnogenol may transcend its free-radical scavenging activities, as suggested by its anti-inflammatory effects, which are partially ascribed to the fact that Pycnogenol inhibits IFN-g-induced expression of ICAM-1 (Bito et al, 2000). Silymarin is a naturally occurring polyphenolic flavonoid compound or flavonolignans antioxidant derived from the seeds of the milk thistle plant Silybum marianu. The beneficial effects of silymarin are primarily the result of its main active constituent silybin, which was shown to be bioavailable in the skin and other tissues following systemic administration (Zhao and Agarwal, 1999). Topical application of silybin before or immediately after UV irradiation has been found to impart strong protection against UV-induced damAbbreviations: CoQ10, coenzyme Q10; UV, ultraviolet

The demonstration profiled here has proven effective in bringing together concepts from acid-base chemistry and electrochemistry.