Rutabaga Research Articles

SeqSNP-Based Targeted GBS Provides Insight into the Genetic Relationships among Global Collections of Brassica rapa ssp. oleifera (Turnip Rape).

Turnip rape is a multi-purpose crop cultivated in temperate regions. Due to its ability to fit into crop rotation systems and its role as a food and feed source, spring-type turnip rape cultivation is on the rise. To improve the crop's productivity and nutritional value, it is essential to understand its genetic diversity. In this study, 188 spring-type accessions were genotyped using SeqSNP, a targeted genotyping-by-sequencing method to determine genetic relationships between various groups and assess the potential effects of mutations within genes regulating major desirable traits. Single nucleotide polymorphism (SNP) alleles at six loci were predicted to have high effects on their corresponding genes' functions, whereas nine loci had country/region-specific alleles. A neighbor-joining cluster analysis revealed three major clusters (I to III). About 72% of cluster-I accessions were of Asian origin, whereas 88.5% of European accessions and all North American accessions were placed in cluster-II or cluster-III. A principal coordinate analysis explained 65.3% of the total genetic variation. An analysis of molecular variance revealed significant differentiation among different groups of accessions. Compared to Asian cultivars, European and North American cultivars share more genetic similarities. Hence, crossbreeding Asian and European cultivars may result in improved cultivars due to desirable allele recombination. Compared to landraces and wild populations, the cultivars had more genetic variation, indicating that breeding had not caused genetic erosion. There were no significant differences between Swedish turnip rape cultivars and the NordGen collection. Hence, crossbreeding with genetically distinct cultivars could enhance the gene pool's genetic diversity and facilitate superior cultivar development.

Characterization of the electropermeabilization induced by pulsed electric field (PEF) technology and its effect on the ultrasonic-assisted drying of yellow turnip

Obtaining snacks from the drying of surplus vegetables is an alternative to reduce waste. A combination of pulsed electric field (PEF) pretreatments and ultrasonic-assisted (US) drying could significantly enhance the process, as this is the aim of this study. PEF pretreatments of yellow turnip significantly affected the cell disintegration index (CDI) and the water holding capacity (WHC): the more intense the PEF treatment, the greater the CDI and the lower the WHC. Both parameters, CDI and WHC, showed a high degree of correlation which indicated that WHC can be an alternative index to CDI to assess PEF effects on food matrices. Regarding yellow turnip drying (40 °C), PEF pretreatments (CDI 0.25 and 0.75) and US application (20.5 kW/m3) significantly accelerated the operation, but it was the combination of both technologies that provided the shortest process (CDI 0.75). PEF could generate changes in the food matrix which enhance the US effects on mass transfer.

Оценка активности пероксидаз, содержащихся в различных растительных источниках

In this study, the decolorization reaction of aqueous solution bromophenol blue dye was carried out in the presence of hydrogen peroxide and peroxidase contained in the roots of horseradish (Armoracia rusticana), radish (Raphanus sativus var. radicula), yellow turnip (Brassica napobrassica), daikon (Raphanus sativus), black radish (Raphanus sativus ‘Niger’), green radish (Raphanus) or stalk of white cabbage (Brassica capitata). The reaction was carried out at an initial dye content of 25,1 μM, a hydrogen peroxide concentration of 0,4 mM, at t = 24 °C and pH 4,01, the peel of various vegetables was used as a source of peroxidase; it was inserted into the reaction without enzyme primary extraction. When using horseradish waste, black radish, white cabbage, turnips, it is possible to get the degree of decolorization of the dye in its aqueous solution by 95%. The maximum rate and Michaelis constants of the enzymatic reaction are calculated by the linearization method in the Linuiver – Burke coordinates. It is shown that the activity of peroxidase contained in the peel of black radish persists with an increase in temperature from 23 to 40 °С.

Biochemical analysis of radish and beet species

The study investigated the biochemical composition and enzyme activities of various radish and beet species, revealing significant variations across different parameters. Reducing sugars, crucial for blood sugar regulation and weight management, showed diverse levels among species, with higher concentrations observed in yellow turnip and white radish. Likewise, fiber content varied, with Raphanus sativus L. var. niger J. Kern exhibiting the highest fiber content. Moisture and mineral content also differed across species, with sugar beet displaying the highest mineral content. Regarding vitamin C content, our findings indicated lower levels compared to previous studies, suggesting potential influences of environmental conditions on vitamin accumulation. Flavonoid content, known for its antioxidant properties, was notably high in black radish compared to other species, highlighting the potential health benefits of flavonoid-rich varieties. Enzyme activities, including catalase, peroxidase, and polyphenol oxidase, varied among species, with white radish and beetroot exhibiting higher catalase activity. These findings highlight biochemical variations among radish and beet species, underscoring their potential health benefits and applications.

Transcriptomic analysis of succulent stem development of Chinese kale (Brassica oleracea var. alboglabra Bailey) and its synthetic allotetraploid via RNA sequencing.

Chinese kale (Brassica oleracea var. alboglabra Bailey, CC) is a succulent stem vegetable in the Brassica family. Its allotetraploid (AACC) vegetable germplasm, which was synthesized via distant hybridization with the colloquially named 'yellow turnip' (B. rapa L. ssp. rapifera Matzg., AA), has a swelling stem similar to CC. To address the molecular mechanism of stem development for CC and AACC, RNA sequencing (RNA-seq) was used to investigate transcriptional regulation of their stem development at three key stages including 28 days, 42 days and the bolting stage (BS) after sowing. As a result, 32,642, 32,665, 33,816, 32,147, 32,293 and 32,275 genes were identified in six corresponding cDNA libraries. Among them, 25,459 genes were co-expressed, while 7,183, 7,206, 8,357, 6,688, 6,834 and 6,814 genes were specifically expressed. Additionally, a total of 29,222 differentially expressed genes (DEGs) were found for functional enrichment as well as many genes involved in plant hormones including gibberellin (GA), abscisic acid (ABA), cytokinin (CTK) and auxin (AUX). Based on gene expression consistency between CC and AACC, the gene families including DELLA, GID, PYR/PYL, PP2C, A-ARR and AUX/IAA might be related to stem development. Among these, eight genes including Bo00834s040, Bo5g093140, Bo6g086770, Bo9g070200, Bo7g116570, Bo3g054410, Bo7g093470 and Bo5g136600 may play important roles in stem development based on their remarkable expression levels as confirmed by qRT-PCR. These findings provide a new theoretical basis for understanding the molecular mechanism of stem development in Brassica vegetable stem breeding.

Transcriptomics Integrated with Metabolomics Unveil Carotenoids Accumulation and Correlated Gene Regulation in White and Yellow-Fleshed Turnip (Brassica rapa ssp. rapa).

Turnip (Brassica rapa ssp. rapa) is considered to be a highly nutritious and health-promoting vegetable crop, whose flesh color can be divided into yellow and white. It is widely accepted that yellow-fleshed turnips have higher nutritional value. However, reports about flesh color formation is lacking. Here, the white-fleshed inbred line, W21, and yellow-fleshed inbred line, W25, were profiled from the swollen root of the turnip at three developmental periods to elucidate the yellow color formation. Transcriptomics integrated with metabolomics analysis showed that the PSY gene was the key gene affecting the carotenoids formation in W25. The coding sequence of BrrPSY-W25 was 1278 bp and that of BrrPSY-W21 was 1275 bp, and BrrPSY was more highly expressed in swollen roots in W25 than in W21. Transient transgenic tobacco leaf over-expressing BrrPSY-W and BrrPSY-Y showed higher transcript levels and carotenoids contents. Results revealed that yellow turnip formation is due to high expression of the PSY gene rather than mutations in the PSY gene, indicating that a post-transcriptional regulatory mechanism may affect carotenoids formation. Results obtained in this study will be helpful for explaining the carotenoids accumulation of turnips.

Microbial Communities and Physiochemical Properties of Four Distinctive Traditionally Fermented Vegetables from North China and Their Influence on Quality and Safety.

The bacterial communities and physicochemical characteristics of four types of extremely distinctive traditionally fermented vegetables (pickled pepper (PP), pickled Brassica napobrassica (PBN), salted flowers of wild chives (SFWC), and pickled cucumber (PC)) were identified and compared from north China. Lactobacillus was the main bacterial genus in PP and PBN samples, with Oceanobacillus only being observed in PBN. The predominant genus in SFWC was Weissella, while in PC they were were Carnimonas and Salinivibrio. At the species level, Companilactobacillus ginsenosidimutans, Fructilactobacillus fructivorans, and Arcobacter marinus were abundant in PP and PBN. Levilactobacillus brevis and Companilactobacillus alimentarius were enriched in PP, and L. acetotolerans, Ligilactobacillus acidipiscis and Pediococcus parvulus were observed in PBN. Weissella cibaria and Kosakonia cowanii were abundant in SFWC. Moreover, tartaric acid was the most physicochemical factor influencing microbial composition, followed by malic acid, titratable acidity (TA), and lactic acid. Furthermore, functional analysis demonstrated that the most genes of the bacterial profiles correlated with carbohydrate metabolism. However, some foodborne pathogens were existed, such as Staphylococcus and Arcobacter marinus. The results of this study provide detailed insight into the relationship between the bacterial communities and physicochemical indices of fermented vegetables, and may improve the quality and safety of traditional Chinese fermented vegetables.

Plant Viruses Can Alter Aphid-Triggered Calcium Elevations in Infected Leaves.

Alighting aphids probe a new host plant by intracellular test punctures for suitability. These induce immediate calcium signals that emanate from the punctured sites and might be the first step in plant recognition of aphid feeding and the subsequent elicitation of plant defence responses. Calcium is also involved in the transmission of non-persistent plant viruses that are acquired by aphids during test punctures. Therefore, we wanted to determine whether viral infection alters calcium signalling. For this, calcium signals triggered by aphids were imaged on transgenic Arabidopsis plants expressing the cytosolic FRET-based calcium reporter YC3.6-NES and infected with the non-persistent viruses cauliflower mosaic (CaMV) and turnip mosaic (TuMV), or the persistent virus, turnip yellows (TuYV). Aphids were placed on infected leaves and calcium elevations were recorded by time-lapse fluorescence microscopy. Calcium signal velocities were significantly slower in plants infected with CaMV or TuMV and signal areas were smaller in CaMV-infected plants. Transmission tests using CaMV-infected Arabidopsis mutants impaired in pathogen perception or in the generation of calcium signals revealed no differences in transmission efficiency. A transcriptomic meta-analysis indicated significant changes in expression of receptor-like kinases in the BAK1 pathway as well as of calcium channels in CaMV- and TuMV-infected plants. Taken together, infection with CaMV and TuMV, but not with TuYV, impacts aphid-induced calcium signalling. This suggests that viruses can modify plant responses to aphids from the very first vector/host contact.

Dissolved Organic Carbon Concentration and Denitrification Capacity of a New Zealand Hill Country Soil After Forage Crop Establishment

Conversion from perennial pasture to forage cropping to increase animal feed production is widely adopted on steep pastoral hill country landscapes in New Zealand. However, the effect of this conversion on the leaching and availability of dissolved organic carbon (DOC) and soil denitrification is unknown. This study examined the effect of a forage crop (swede—Brassica napobrassica Mill.) establishment on the DOC concentration and denitrification capacity of a hill country soil (Typic Eutrudept) in the lower North Island of New Zealand. Pasture was cleared using selected agrochemicals and sown to swede via a unique surface sowing technique (no cultivation). Soil was sampled once before and multiple times after crop establishment. The sampled soils were compared to soils from adjacent pasture plots. The results suggest that DOC concentration in the subsoil (> 30 cm) and denitrification capacity of the soil profile (100 cm) were generally not affected by the establishment of the forage crop within a 1-year period, without animal grazing. However, forage crop establishment resulted in an initial increase (by > 55%) in the nitrate concentration of the surface 20 cm soil depth on the sixth month after crop establishment. However, the subsoil (> 20 cm) nitrate concentrations in the cropped system were similar to the pasture system. This suggests that the establishment of the brassica forage crop, using the surface sowing technique, did not pose a risk of increased nitrate leaching from this pastoral hill country soil.

A Neural Device with Individually Addressable Microelectrode Array Suitable for Simultaneous Measurement of Catecholamines: Fabrication and Characterization

Investigation of catecholamines (dopamine: DA, norepinephrine: NE and epinephrine EP) has been of importance of the crucial roles that these molecules play in neurological function and related diseases. Due to the similar chemical structures and oxidation potentials of these compounds, it has been a challenge to use simple electrochemical techniques to differentiate them in mixtures.1 Redox cycling is known to have the capability to differentiate between species based on the propensity of the compounds to diffuse to and produce an electrochemical response at the neighboring electrode.2 The oxidized species generated at an electrode (generator) can diffuse to neighboring electrodes held at a reducing potential (collector) that will yield the original species. This process can occur multiple times and can produce an amplified signal. If the oxidized form of the species is electrochemically inactive or inactivated through following chemical reactions, selectivity can be achieved for the electroactive molecules arriving at the collector. This can be the basis of separating and detecting species using redox cycling.The ECC’ mechanism of catecholamines takes place at different rates, in the order of EP > NE > DA, and can lead to differentiation based on the spatial distribution that is probed by the electrode array undergoing redox cycling.4 The purpose of our research is to study the fundamental electrochemical redox cycling behavior of DA, NE and EP. By understanding this behavior, it can then be determined whether their simultaneous detection in more complex samples will be feasible. We will report on miniaturized probes designed to meet requirements of a redox cycling approach for in vivo measurements. These are: 1) mechanical robustness for insertion in the brain without breakage or bending, 2) suitable dimensions to minimize damage to brain tissue and 3) suitable number and design of electrodes for optimal electrochemical performance. The substrate of the fabricated probe is an 80 µm thick SU-8 polymer. The shank is 100 µm wide and 6 mm long to reach deep areas of the rat’s striatum. The probe has an array of nine parallel gold electrodes each of which are 4µm wide with a gap of 4 µm in between.We will report the process, results, and challenges for design, fabrication, and implementation of a probe, suitable for neural studies. The characterization of the probe with a model compound and the results from CA measurements using redox cycling will be shown. We will discuss the next steps to improve the design of electrodes and experiments to achieve desirable limits of detection and sensitivity for in vivo measurements. References Hawley, M. D.; Tatawawadi, S. V.; Piekarski, S.; Adams, R. N. Journal of the American Chemical Society 1967, 89, 447-450.Hu, Mengjia; Fritsch, Ingrid. Analytical Chemistry 2015, 87, 2029−2032.Ciolkowski, E. L.; Maness, K. M.; Cahill, P. S.; Wightman, R. M.; Evans, D. H.; Fosset, B.; Amatore, C. Analytical Chemistry 1994, 66, 3611-3617.Ciolkowski, E. L.; Cooper, B. R.; Jankowski, J. A.; Jorgenson, J. W.; Wightman, R. M. Journal of the American Chemical Society 1992, 114, 2815-2821.

Effect of particle size on functional properties of Brassica napobrassica leaves powder. Starch interactions and processing impact

The aim of this work was to determine the physicochemical and functional properties of a Brassica napobrassica leaves powder sieved at three particle sizes. Moreover, in order to understand the potential interactions between the Brassica napobrassica leaves powder and starch, the pasting properties were assessed and the effect of pH (4–9) and temperatures (70–90 °C) on the phenolic compounds and antiradical activities were also evaluated. Particle size had an effect on physicochemical and functional properties of the vegetable powder. Vegetable fractions affected the apparent viscosity of starch suspension along heating and cooling, with larger effect during heating. The effect of the processing conditions on the functional properties of starch suspensions was influenced by the powder particle sized and the type of starch used. Maize starch seemed to interact more with phenolic compounds than rice starch, which resulted in a protective effect against pH and temperature variations, leading to higher antiradical activities.

Production and characterization of intergeneric hybrids by crossing radish with turnip and with Chinese kale

Distant hybridization can enrich the genetic background and diversity of crops by combining different species, and integrate the favorable parental traits or create heterosis. In the present study, intergeneric hybridization was performed between radish and turnip and between radish and Chinese kale by hand emasculation followed by tissue culture of putative hybrid seeds. A total of three and one hybrids were obtained from the cross of ‘Long yellow turnip’ and ‘Golden turnip’ with radish, respectively, but no hybrids were obtained in their reverse cross, indicating that the same cross combination has a large difference in the reciprocal crosses, and that the hybrid has certain unidirectionality. The majority of the hybrids of radish and turnip showed male sterility, white petals, and intermediate performance in most morphological traits when compared to their parents. Four true hybrids were obtained by the cross ‘Thin neck round radish’ × ‘Yellow flower kale’, while no hybrids were obtained by reverse cross combination. The hybrids looked more like their Chinese kale parents in having inflated stems. All putative intergeneric hybrids were confirmed by agronomic characteristics, chromosome counting, molecular markers, and pollen viability. Three kinds of hybrids were confirmed as genuine hybrids possessing 19, 19, and 18 chromosomes in their corresponding somatic cells by cytological observation. In addition, three kinds of allotetraploids were produced with 38, 38, and 36 chromosomes when chromosome doubling was achieved. In comparison with the diploid hybrid, the pollen viabilities of allotetraploids were significantly improved and a small number of seeds were produced. The improvements of these amphihaploids as useful genetic resources and the potential of intergeneric hybridization to enlarge the gene pool for radish, turnip, and Chinese kale breeding are discussed.

Effect of forage crop establishment on dissolved organic carbon dynamics and leaching in a hill country soil

AbstractIntensive agricultural activities could affect the dynamics and leaching of dissolved organic carbon (DOC) and nitrate from agricultural soils to receiving waters. This study investigated soil DOC dynamics immediately (0–12 days) after spraying a hill country perennial pasture with agrochemicals to establish a winter forage crop for supplementary feed production. Two treatments were examined—perennial pasture (without agrochemicals) and swede (Brassica napobrassica Mill.) cropping (after spraying with agrochemicals), both growing on a Typic Eutrudept. Soil samples were collected from various depths down to 1 m, before the application of agrochemicals (day 0) and 1, 6 and 12 days thereafter. Dissolved organic carbon concentration below the surface soil (<5 cm) was generally not altered by the agrochemicals. This was further proved by the isotopic monitoring of DOC leaching on this soil. Conversely, the agrochemicals significantly (p = 0.03) increased DOC concentration within the 0–5‐cm soil depth on day 1, due to the direct contribution of organic molecules and/or displacement of organic compounds at adsorption sites by the agrochemicals; and on day 6, due to root necromass decomposition. The increase of nitrate in soil solution at this depth (0–5 cm) on days 6 and 12 suggests that the agrochemicals may have also enhanced nitrogen (N) mineralization in the surface soil. However, the significantly (p = 0.04) higher DOC/nitrate (molar ratio) of the agrochemical treatment suggests that the agrochemicals used for clearing out pasture before forage crop establishment could lead to a short‐term increase in surface soil denitrification.

A profile of arsenic species in different vegetables growing in arsenic-contaminated soils

ABSTRACTSix different vegetables (black radish, black salsify, lettuce, parsnip, Savoy cabbage and Swede turnip) were cultivated in model pot experiments. The soils used in the experiments originated from two mining and smelting sites in the Czech Republic – Příbram and Kutná Hora, respectively. These soils showed differences in physicochemical properties and/or total contents of arsenic, reaching 36.0 ± 1.0 and 473 ± 10 mg As kg−1, respectively. The four most common anionic arsenic compounds (arsenite As(III), arsenate As(V), dimethylarsinate (DMA), methylarsonate (MA)) were determined by high-performance liquid chromatography coupled to an inductively coupled plasma mass spectrometer. The concentration of arsenic species determined in edible plant parts decreased in the following order: Higher proportions of both DMA and MA were found in the aboveground edible parts (leaves) compared to the underground parts (tubers). The results indicate that the distribution of arsenic compounds differed predominantly according to individual plant species whereas almost no effect was observed due to the different soil properties. However, a higher arsenic concentration in soils resulted in more arsenic in the plant independently of the aboveground biomass (leaves) or the underground plant parts (tubers).

Redox Cycling Behavior of Catecholamines and Their Mixtures at Different Diffusion Distances: Steps Toward Quantitative Speciation

Investigation of catecholamines (dopamine: DA, norepinephrine: NE and epinephrine EP) has been of importance, because of the crucial roles that these molecules play in neurological function and related diseases. Due to the similar chemical structures and oxidation potentials of these compounds, it has been a challenge to use simple electrochemical techniques to differentiate them in mixtures.1 Redox cycling is known to have the capability to differentiate between species based on the propensity of the compounds to diffuse to and produce an electrochemical response at the neighboring electrode.2 The oxidized species generated at an electrode (generator) can diffuse to neighboring electrodes held at a reducing potential (collector) that will yield the original species. This process can occur multiple times and can produce an amplified signal. If the oxidized form of the species is electrochemically inactive, selectivity can be achieved for the electroactive molecules at the collector. Chemical reactions that can happen during the transfer between generator and collector can also convert the oxidized species to an electroinactive one and prevent a signal at the collector electrode, as well. This can be the basis of separating and detecting species using redox cycling. In their ECC’ mechanism, catecholamines undergo a two-electron oxidation (E) to yield the o-quinone.3 The o-quinone form can then go through an internal cyclization reaction (C) to yield the leucoaminochrome. The leucoaminochrome and o-quinone forms can react with each other (C’) to yield the original catecholamine and the aminochrome form. The internal cyclization reaction that is involved in the C part of the mechanism occurs at different rates for the different catecholamines. The apparent rate constants at pH=7.4 in phosphate buffer have been reported to be 0.13 ± 0.05 s-1, 0.98 ± 0.52 s-1 and 87 ± 10 s-1 for DA, NE and EP, respectively.4 Due to the difference in these rate constants, the species can be distinguished by spatial distribution based on the survival of the o-quinone from the following chemistry. Step C in the mechanism can also affect the number of times the species can go back and forth between the electrodes and therefore the amplification of the signal, depending on the species. The purpose of our research is to study the fundamental electrochemical redox cycling behavior of DA, NE and EP. By understanding this behavior, it can then be determined whether their simultaneous detection in more complex samples will be feasible. Recent developments from our laboratory will be discussed. We are using microfabricated chips with individually-addressable microelectrode arrays to activate various combinations of electrodes in the redox cycling experiments. By activating different electrodes on the array, greater distances between the collector and generator electrodes can be achieved leading to longer transit times for the molecules to move between electrodes. This study will lead to the generation of a calibration map for different gaps, ratios of catecholamines, and concentrations. There is a greater decrease in collector signal with increasing gap width (beyond the loss due to diffusion) for species with greater rate constants for step C. Epinephrine does not exhibit a reduction signal when the gap is set at 4-µm.2 Norepinephrine’s signal decreases as a function of increasing gap more sharply than dopamine’s. There is no observed collector signal for NE at the collector electrode, which is activated 28-µm away from the collector. The oxidation signal of the mixtures of catecholamines decreases even further due to the following chemistry producing the leucoaminochrome and increased concentrations of o-quinone and leucoaminochrome molecules. References Hawley, M. D.; Tatawawadi, S. V.; Piekarski, S.; Adams, R. N. Journal of the American Chemical Society 1967, 89, 447-450. Hu, Mengjia; Fritsch, Ingrid. Analytical Chemistry 2015, 87, 2029−2032.Ciolkowski, E. L.; Maness, K. M.; Cahill, P. S.; Wightman, R. M.; Evans, D. H.; Fosset, B.; Amatore, C. Analytical Chemistry 1994, 66, 3611-3617.Ciolkowski, E. L.; Cooper, B. R.; Jankowski, J. A.; Jorgenson, J. W.; Wightman, R. M. Journal of the American Chemical Society 1992, 114, 2815-2821.

Forage Brassicas Stockpiled for Fall Grazing: Yield and Nutritive Value

Forage brassicas can potentially be used to extend the grazing season into the fall for beef cattle operations, thereby reducing input costs. Nine cultivars of forage brassicas were seeded on two planting dates, and their yield and nutritive value were measured for two fall harvest dates over 2 years in northern Colorado. Cultivars evaluated included three turnips (Brassica rapa L.; Purple Top, Barkant, and Appin); three rapes (Brassica napus L.; Winfred, Barnapoli, and Bonar); Groundhog radish (Raphanus sativus L.); Major Plus swede [Brassica napobrassica (L.) Mill.]; and Pasja hybrid (Chinese cabbage [Brassica rapa subsp. chinensis (L.) Hanelt] × turnip hybrid). Dry matter (DM) yield, crude protein (CP), neutral detergent fiber (aNDF), and in vitro true digestibility (IVTD) were evaluated using a three‐way factorial treatment structure. Planting date was the overriding factor impacting DM yield with an overall reduction of 3770 lb/acre by delaying planting until mid‐August. Additional forage was also obtained by delaying the harvest date until mid‐November, but the increase was minor compared with yields obtained with earlier planting. The rapes tended to yield the highest when seeded in mid‐ to late July, but there were only minor differences among cultivars seeded in mid‐August. Fiber content of forage brassicas was low (19.0–25.2%), and CP content (18.6–25.5%) and IVTD (85.5–92.9%) were above the requirements for all classes and stages of beef cattle. Forage brassicas had minor changes in nutritive value during the fall, which makes them suitable for stockpiling when combined with lower‐quality forages to dilute their high nutrient content and thereby minimize the potential for rumen upset.

Effect of freshwater sapropel on plants in respect to its growth-affecting activity and cultivable microorganism content

A positive effect of organic-rich sediments sapropels on plant growth has been suggested in general, but has not been proven on an experimental basis. The aim of the present investigation was to study biological activity of freshwater sapropel and its product including analyses of plant growth-affecting activity and cultivable microorganisms. Besides mineral nutrients, sapropel contained unspecified substances promoting plant growth in a seedling growth test with beetroot, Swedish turnip, carrot and tomato. Summed plant growth-affecting activity of sapropel and sapropel-containing substrate BioDeposit Agro had a relatively high growth-enhancing component together with an extremely low growth-inhibiting component. Substrate amendment with BioDeposit Agro resulted in a significant increase in dry matter accumulation only in lettuce plants but not in winter rye plants. High level of aerobic heterotrophic bacteria, high level of yeasts and variable level of filamentous fungi with a low diversity were found in all sapropel samples tested. Plant growth-stimulating activity negatively correlated with the number of colony forming units of both yeasts and fungi. There was no correlation between the number of bacteria and plant growth-stimulating activity.

Screening of Brassica germplasm for resistance to Plasmodiophora brassicae pathotypes prevalent in Canada for broadening diversity in clubroot resistance

Hasan, M. J., Strelkov, S. E., Howard, R. J. and Rahman, H. 2012. Screening ofBrassicagermplasm for resistance toPlasmodiophora brassicae pathotypes prevalent in Canada for broadening diversity in clubroot resistance. Can. J. Plant Sci. 92: 501–515. Clubroot disease of crucifers, caused by Plasmodiophora brassicae, poses a threat to the Canadian canola industry, and the development of resistant cultivars is urgently needed. Germplasm resistant to local pathotype(s) is the prime requirement for breeding clubroot-resistant cultivars. The objective of this study was to identify Brassica germplasm possessing resistance to P. brassicae pathotypes prevalent in Alberta. Pathotype-specific resistance was identified in the diploid species Brassica rapa (AA) and B. oleracea (CC), and in the amphidiploid B. napus (AACC). Among B. rapa genotypes, turnip was the most resistant, followed by winter type and spring type oilseed rape. The rutabaga group of B. napus, on the other hand, was homogeneous for resistance to Can...

Genetic and physiological determinants ofStreptomyces scabiespathogenicity

SUMMARY Common scab is a severe disease worldwide affecting tap root crops and potato tubers. It is caused by soil-borne filamentous bacteria belonging to the genus Streptomyces. Streptomycetes usually are saprophytic microorganisms, but a few species have acquired the ability to infect underground plant tissues. The predominant causal agent of potato scab worldwide is Streptomyces scabies. The production of phytotoxins called thaxtomins is essential for the virulence of common scab-causing agents. The genes involved in the biosynthetic pathway of thaxtomins and other virulence genes are clustered on a large pathogenicity island. The pathogenicity island can be mobilized and transferred to nonpathogenic relatives, leading to the emergence of new pathogenic streptomycetes. In most pathogenic Streptomyces species, thaxtomin A is the predominant form found. The regulation of thaxtomin A synthesis is complex. Although the plant-derived compound cellobiose is now recognized as the inducer of thaxtomin A synthesis at a genetic level, other molecules (including aromatic amino acids and some secondary metabolites) show inhibitory effects on the production of the toxin. This paper is an overview of common scab with a focus on S. scabies and its virulence mechanisms. Streptomyces scabies (Thaxt.) Lambert and Loria; Kingdom Bacteria; Phylum Actinobacteria; Class Actinomycetes; Order Actinomycetales; Family Streptomycetaceae; genus Streptomyces; species scabies or scabiei. Streptomyces scabies (syn. S. scabiei) has a broad host range comprising tuber vegetables and most tap root crops. Streptomyces scabies causes common scab on potato (Solanum tuberosum), beet (Beta vulgaris), carrot (Daucus carota), parsnip (Pastinaca sativa), radish (Raphanus sativus), rutabaga (Brassica napobrassica) and turnip (Brassica rapa). Disease symptoms: Common scab symptoms appear as randomly distributed shallow, raised or deep-pitted corky lesions. Their size and colour are quite variable, but lesions typically are brown with a diameter of a few millimetres. No above-ground symptoms disclose the presence of the disease as aerial tissues of scab-infected plants remain healthy. Streptomyces scabies also inhibits the growth of seedlings in monocot and dicot plants. http://www.sanger.ac.uk/Projects/S_scabies, http://www.potatodiseases.org/scab.html, http://www.uri.edu/ce/factsheets/sheets/potatoscab.html.

Effect of different cooking methods on the antioxidant activity of some vegetables from Pakistan

SummaryThe effects of different cooking methods (boiling, frying and microwave cooking) on the antioxidant activity of some selected vegetables (peas, carrot, spinach, cabbage, cauliflower, yellow turnip and white turnip) were assessed by measuring the total phenolic contents (TPC), reducing power and percentage inhibition in linoleic acid system. TPC (gallic acid equivalents g/100 g of dry weight) and reducing power of the methanolic extracts of raw‐, microwaved‐, boiled‐ and fried vegetables ranged 0.333–2.97, 0.52–2.68, 0.48–2.08, 1.00–2.02 and 0.391–2.24, 0.822–1.10, 0.547–1.16, 0.910–4.07, respectively. The level of inhibition of peroxidation ranged 71.4–89.0, 66.4–87.3, 73.2–89.2 and 77.4–91.3%, respectively. Antioxidant activity of the vegetables examined was appreciably affected because of varying cooking treatments. TPC of vegetables, generally, decreased by boiling, frying and microwave cooking. There was a significant (P < 0.05) increase in reducing power as a result of frying. However, boiling and microwave cooking did not affect reducing power. Inhibition of peroxidation increased by boiling and frying, whereas, in contrast it was decreased by microwave cooking. The results of the present investigation showed that all the cooking methods affected the antioxidant properties of the vegetables; however, microwave treatment exhibited more deleterious effects when compared with those of other treatments. Thus an appropriate method might be sought for the processing of such vegetables to retain their antioxidant components at maximum level.