Daikon Radish Research Articles

Influence of cover crops on soil aggregate stability, size distribution and related factors in a no-till field

Soil aggregation plays an essential role in maintaining soil structure. A three-year field experiment was undertaken to explore the effects of cover crops on soil aggregate stability indices (mean weight diameter, water-stable aggregates greater than 0.25 mm, and soil erodibility factor), size distribution and their correlations with nine soil physical and chemical properties (soil bulk density, pH, organic carbon, total nitrogen, C/N, calcium, phosphorus, potassium, and cation exchange capacity) at 0–5 and 5–10 cm depths in a Marietta silt loam soil in a no-till field, Northeastern Mississippi. The cover crop treatments included elbon rye (Secale cereale L.), daikon radish (Raphanus sativus ssp. acanthiformis), Austrian winter field peas (Lathyrus hirsutus), and their mixture. The samples were wet-sieved to five size classes of aggregates (> 2, 2–1, 1–0.5, 0.5–0.25, and < 0.25 mm). Results showed that the < 0.25 mm aggregates dominated (50.95–78.02 %) soil aggregate size distribution at 0–5 and 5–10 cm depths. The rye plot soil displayed the greatest values for mean weight diameter (0.58 mm) in the two soil depths. Soil water-stable aggregates greater than 0.25 mm value under peas was significantly higher by 68.61 % compared to the no cover crop treatment at 0–5 cm depth, while soil erodibility factor did not change significantly. Mean weight diameter, water-stable aggregates greater than 0.25 mm, soil erodibility factor, 1–0.5 mm aggregates, and < 0.25 mm aggregates were significantly correlated with soil organic carbon, pH, bulk density, phosphorus, and potassium. The dominant factors driving changes in three aggregate stability indices and size fractions (excluding 2–1 mm aggregates) were bulk density and pH. Furthermore, high pH restricted soil aggregate stability and size distribution. This study demonstrated the positive impact of cover crops, specifically peas and rye, on soil aggregate stability and size distribution. This study will provide valuable information for future research on soil stabilization in crop production management systems.

Evaluation of the nitrogen uptake efficacy of daikon radish under greenhouse conditions on sandy soils

AbstractCover crops can be a great addition to agricultural systems to improve soil health and nutrient cycling. One of the many qualities that cover crops possess is recovering residual nutrients. This study was established to estimate daikon radish (Raphanus sativus var. Longipinnatus) nitrogen (N) uptake, partitioning, and accumulation in a short time in Florida conditions. In greenhouse conditions, two Florida sandy soils were planted with daikon radish with three N rates (0, 50, and 101 kg N ha−1 as urea) following a randomized complete block with four replications. The treatments were organized in a two‐by‐three full factorial arrangement with the three N fertilizer rates. Biomass accumulation, N uptake, and partitioning into shoots and roots were estimated, and residual soil N was calculated. Increasing the amount of N applied to daikon radish plants did not increase biomass production or N accumulation in the shoots and roots of the plants. Daikon radish plants grown without N fertilization were able to produce a similar amount of biomass as those with N applications in their early growth stage. This suggests that daikon radish has the potential to adapt to the sandy soils of Florida and could efficiently utilize the residual soil N. This study shows the potential use of daikon radish as a cover crop in the row middles of citrus groves. The findings suggest that daikon radish plants could thrive in these unfertilized areas and offer promising benefits to the citrus orchards in terms of providing ground cover and additional advantages.

The Impact of Peach Rootstocks and Winter Cover Crops on Reproduction of Ring Nematode

Two peach rootstocks (‘Guardian’ and ‘MP-29’) and ten winter cover crops (rye, wheat, barley, triticale, oat, Austrian winter pea, crimson clover, balansa clover, hairy vetch, and daikon radish) were evaluated in a greenhouse environment to determine their suitability to host ring nematode, Mesocriconema xenoplax. Each crop was inoculated with 500 ring nematodes, and the experiments were terminated 60 days after inoculation. The reproduction factor (ratio of final and initial nematode population) ranged from 0 to 13.8, indicating the crops greatly varied in their host suitability to ring nematode. ‘Guardian’ has been known to tolerate ring nematode; however, results from the current study suggest the tolerance statement is anecdotal. Another peach rootstock, ‘MP-29’, was also a good host for ring nematode, suggesting an urgency to develop ring nematode-resistant peach rootstocks. Wheat supported the least to no nematode reproduction while pea supported the greatest reproduction. The rest of the cover crops were poor to good hosts to ring nematodes. Although planting cover crops in peach orchards is not common, employing non or poor host crops can help suppress nematodes in addition to having soil health benefits. Furthermore, peach breeding programs should focus on finding and introgressing ring nematode resistance in commercial rootstocks.

Antioxidant and antimicrobial activities of mango peel and radish peel-a comparative investigation

The present study investigated the antioxidant and antimicrobial activities of Bao mango and daikon radish peel (Thai variety) ethanolic extracts. The percentage extraction yield of radish peel was higher compared to the mango peel (p &amp;lt; 0.05). However, Mango peel extract (MPE) contained higher total phenolic content (TPC) than radish peel extract (RPE) (p &amp;lt; 0.05). Similar to the TPC value, antioxidant activities including DPPH radical scavenging activity, reducing power, and peroxidation inhibition were higher in the MPE, compared to the RPE, except for metal chelating activity. The antimicrobial analyses suggested that the MPE showed lower minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values compared to the RPE (p &amp;lt; 0.05) against Gram-positive and Gram-negative bacteria. High-performance liquid chromatography (HPLC) revealed that mangiferin was the major phenolic compound present in MPE, followed by 3, 4 dihydroxybenzoic acid. Therefore, MP could be used as a promising natural antioxidant and antimicrobial agent for food applications.

Cover crop impacts on nitrogen losses and environmental damage cost

There is a need to explore management practices that reduce nitrate (NO3-) leaching and aid in meeting current greenhouse gas reduction goals. Tile drainage involves using perforated pipes to remove excess subsurface water from agricultural fields, also removing nutrients. The inclusion of cover crops in tile-drained systems in the Midwest has been shown to reduce NO3- losses and is potentially a strategy to mitigate soil nitrous oxide (N2O) emissions. The objectives of this research were to 1) evaluate cumulative soil NO3- and soil N2O losses with and without the inclusion of cover crops in a corn-soybean rotation on a tile-drained landscape and; 2) assess the environmental damage cost (EDC) of N losses with and without the inclusion of cover crops in a corn-soybean rotation on a tile-drained landscape. Corn (Zea mays L.) was grown in 2017, and soybean (Glycine max L.) in 2018. The cover crop used in this experiment was a 92% cereal rye (Secale cereal L.) and 8% daikon radish (Raphanus sativus L.) blend. Treatments included cover crop inclusion, no cover crop inclusion, and a zero control, which did not include cover crops or receive N fertilization. Each treatment was replicated three times in individually tile-drained plots established in Lexington, IL during the 2017 and 2018 growing seasons. In 2017, cover crop inclusion led to a reduction in NO3– losses of over 50% when compared to the no cover and zero control. In 2018, total N losses were identical; however, there was an increase in soil N2O emissions across all treatments compared to 2017. Despite the apparent tradeoff between N loss pathways in 2018, the overall EDC was reduced primarily because of the reduction in NO3- loss in the presence of cover crops. The results of this study indicated that the inclusion of a cover crop resulted in a sizeable reduction in N loss during the corn year that equated to a 64% reduction in EDC across a two-year crop rotation.

Comparative analysis of isothiocyanates in eight cruciferous vegetables and evaluation of the hepatoprotective effects of 4-(methylsulfinyl)-3-butenyl isothiocyanate (sulforaphene) from daikon radish (Raphanus sativus L.) sprouts.

The contributions of cruciferous vegetables to human health are widely recognised, particularly at the molecular level, where their isothiocyanates play a significant role. However, compared to the well-studied isothiocyanate 4-(methylsulfinyl)butyl isothiocyanate (sulforaphane) produced from broccoli sprouts, less is known about the pharmacological effects of other isothiocyanates and the stage of vegetables preferable to obtain their benefits. We analysed the quantity and quality of isothiocyanates produced in both the sprouts and mature stages of eight cruciferous vegetables using gas chromatography-mass spectrometry (GC-MS). Additionally, we investigated the hepatoprotective effects of isothiocyanates in a mouse model of acute hepatitis induced by carbon tetrachloride (CCl4). Furthermore, we explored the detoxification enzyme-inducing activities of crude sprout extracts in normal rats. Among the eight cruciferous vegetables, daikon radish (Raphanus sativus L.) sprouts produced the highest amount of isothiocyanates, with 4-(methylsulfinyl)-3-butenyl isothiocyanate (sulforaphene) being the dominant compound. The amount of sulforaphene in daikon radish sprouts was approximately 30 times that of sulforaphane in broccoli sprouts. Sulforaphene demonstrated hepatoprotective effects similar to sulforaphane in ameliorating CCl4-induced hepatic injury in mice. A crude extract of 3-day-old daikon radish sprouts upregulated the detoxifying enzyme glutathione S-transferase (GST) in the liver, whereas the crude extract of broccoli sprouts showed limited upregulation. This study highlights that daikon radish sprouts and sulforaphene have the potential to serve as functional food materials with hepatoprotective effects. Furthermore, daikon radish sprouts may exhibit more potent hepatoprotective effects compared to broccoli sprouts.

Cover crop-mediated soil carbon storage and soil health in semi-arid irrigated cropping systems

Cover cropping is considered a climate-smart strategy to regenerate low-fertility soils in arid and semi-arid regions. However, the mechanisms of soil organic carbon (SOC) storage and soil health improvement in semi-arid irrigated cropping systems are poorly understood. The main goal of this study was to evaluate cover crop effects on various physical, chemical, and biological indicators of soil health in an irrigated silage corn (Zea mays L.)–sorghum [Sorghum bicolor (L.) Moench] rotation and understanding how changes in soil health contribute to SOC storage. We evaluated various SOC and nitrogen (N) pools, and microbial community structure under cover crop mixture of grasses, brassicas, and legumes (GBL), grasses and brassicas (GB), grasses and legumes (GL), and no cover crops (NCC) control for four years. Grasses included annual ryegrass (Lolium multiflorum Lam.) and winter triticale (× Triticosecale Wittmack), brassicas included turnip (Brassica rapa subsp. rapa L.) and daikon radish (Raphanus sativus var. Longipinnatus Bailey), and legumes included pea (Pisum sativum subsp. arvense L.) and berseem clover (Trifolium alexandrinum L.). Soil C pools: SOC, potentially mineralizable C, microbial biomass C, mineral-associated organic C (MAOC), and particulate organic C (POC) were greater with cover crops than without, but the effects were not consistent in all study years. Soil organic N was also greater under cover crops than under NCC. Soil C-to-N (C:N) ratio increased over the years but was similar among treatments. Cover crops used N and soil water to grow, significantly reducing soil inorganic N content and water-filled pore spaces in the first two years. However, fungal and bacterial communities grew better under cover crops with a high fungi-to-bacteria ratio than under NCC. The soil MAOC content was related to microbial community and enzyme activity while POC was affected by soil physicochemical conditions, specifically soil pH and mineral N availability, highlighting two major pathways of SOC sequestration in semi-arid cropping systems. This study showed how cover crops enhance SOC storage and soil health in semi-arid cropping systems.

Shoot Yield and Mineral Nutrient Concentrations of Six Microgreens in the Brassicaceae Family Affected by Fertigation Rate

Microgreens have become an important specialty crop valued by their varying texture, vibrant colors, and nutrient-dense features. As the number of species and cultivars rapidly increases for microgreen production, fertigation requirements in relation to shoot production and nutrient compositions remain unclear. This study aimed to investigate the shoot yield, visual quality, and mineral nutrient concentrations of six microgreens in the Brassicaceae family including the ‘Waltham’ broccoli, ‘Red Acre’ cabbage, Daikon radish, ‘Red Russian’ kale, pea, and Rambo radish in two experiments in December 2020 and January 2021. Each microgreen was fertigated with 120 mL of fertilizer solution daily for five consecutive days with a rate of 0, 70, 140, 210, or 280 mg·L−1 N from a general-purpose fertilizer. Broccoli, Daikon radish, and kale similarly produced the highest fresh shoot weights of 916.5 to 984 g·m−2 in December 2020, while pea produced the highest fresh shoot weight of 2471 g·m−2 in January 2021 among cultivars. The fertigation rates of 140, 210, and 280 mg·L−1 N resulted in similar fresh and dry shoot weights of selected microgreens, suggesting 140 mg·L−1 N should be sufficient for microgreen fertilization. Mineral nutrients in microgreens varied among cultivars: pea microgreens had the highest nitrogen (N) concentrations of 70.6 to 75.2 mg·g−1 in December 2020 and 72.1 to 75.4 mg·g−1 in January 2021; and cabbage microgreens were rich in calcium (Ca) in both experiments. The kale, pea, and Rambo radish microgreens contained the highest concentrations of iron (Fe) and manganese (Mn) in December 2020. The fertigation rate affected macronutrient concentrations but did not affect micronutrient concentrations including Fe, Mn, or zinc (Zn).

Line Spread Test (LST) Results for Commercially Available Universal Design Foods (UDF: Can be Crushed with the Tongue; “Daikon Radish with Minced Chicken Sauce” and “Sweet Potato and Bean Paste”) – Combination Results of Two Types of UDF and Eight Types of Thickeners

Line Spread Test (LST) Results for Commercially Available Universal Design Foods (UDF: Can be Crushed with the Tongue; “Daikon Radish with Minced Chicken Sauce” and “Sweet Potato and Bean Paste”) – Combination Results of Two Types of UDF and Eight Types of Thickeners

Impact of Cover Crops and Nitrogen Management on Soil Bacterial Alpha Diversity

ABSTRACT Corn (Zea mays L.) nitrogen (N) strategies that account for fertilizer timing and source may differentially affect soil bacterial communities and require further validation when preceded by cover crops (CC). Field studies were conducted (2014–2016) evaluating the effects of daikon radish [Raphanus sativus (L.)], forage oat [Avena sativa (L.)], and no CC combined with multiple N management strategies on soil bacterial alpha diversity metrics. Nitrogen strategies consisted of 179 kg N ha−1 applied pre-plant incorporated (PPI), poultry litter (PL) (61 kg N ha−1) applied PPI plus sidedress (SD) N at V11 (11 leaf collars), starter N (45 kg N ha−1) applied 5 cm beside and below the furrow followed by SD at V4 (4 leaf collars), V11, or 50:50 (split) V4 and V11, and a zero N control. In 1 of 2 years, radish reduced diversity 47–53% during active growth compared to remaining treatments. Inverse relationships regarding diversity of in-row (IR) soils at R1 (silking) and grain yield indicated that increased bacterial diversity did not correspond to increased grain production. Relative to PL and the zero-N control, starter N strategies reduced R1 rhizosphere bacterial diversity, evenness, and richness. Combining organic with soluble N sources may stabilize changes to soil alpha diversity metrics at corn silking.

Direct ammonium recovery from the permeate of a pilot-scale anaerobic MBR by biochar to advance low-carbon municipal wastewater reclamation and urban agriculture

The rapidly evolving global climate change has an unprecedented impact sustainable water supply, but also challenges and water shortage global food security. In such a dynamic situation, this study explored direct recovery of ammonium from the effluent of a pilot-scale anaerobic membrane bioreactor (AnMBR) treating actual municipal wastewater via biochar adsorption, while the use of produced ammonium-loaded biochar for urban agriculture was also demonstrated. Results showed that modified biochar could remove almost all ammonium in the pilot AnMBR permeate at an empty bed contact time of 30 mins. Results showed that ammonium extracted from the ammonium-loaded biochar could promote the germination of Daikon radish seeds. It was further observed that the fresh weight of Pak Choi (a typical leafy vegetable) planted in the soils augmented with the ammonium-loaded biochar was 42.5 g per vegetable versus 18.5 g per vegetable in the control, indicating a 130 % of increase in the Pak Choi productivity. In addition, the Pak Choi in grown the ammonium-loaded biochar augmented soils appeared to be much bigger with larger leaves compared to the control. It was also worth to note that the ammonium-loaded biochar could significantly stimulate the root development of Pak Choi, i.e., 20.7 cm over 10.5 cm obtained in the control. More importantly, the amount of carbon emission reduced through returning ammonium-loaded biochar to urban agriculture could offset the treatment process-associated direct and indirect carbon emission.

Can relative sensitivity of cover crop species to chloroacetamide and pyrazole herbicides be exploited to design interseeding mixtures?

AbstractDrill-interseeding cover crops into standing corn (V3 to V5 growth stage) provides opportunities for increasing functional diversity in cropping systems by facilitating use of cover crop mixtures that include grass, legume, and brassica species. Designing herbicide-based weed control programs that negotiate tradeoffs between crop protection and environmental goals when interseeding mixtures remains a major challenge. The objective of this study was to use greenhouse-based dose-response assays to describe the relative sensitivity of 12 cover crop species that differ in traits, including taxonomic group and seed mass, to chloroacetamide (acetochlor, dimethenamid, S-metolachlor; Group 15 herbicides as categorized by the Weed Science Society of America) and pyrazole (pyroxasulfone; Group 15) herbicides. Nonlinear models were fit, and effective doses were estimated (ED50) to compare relative sensitivities of cover crop species to each herbicide. Brassica species (winter canola, Dwarf Essex rape, daikon radish) were less sensitive than small-seeded legumes (medium red clover, crimson clover) and grasses (annual ryegrass) in response to each chloroacetamide, but similar in response to pyroxasulfone. Austrian winter pea, a large-seeded legume, was less sensitive to each herbicide compared to other legumes (crimson clover, medium red clover, hairy vetch). Cereal rye and triticale were less sensitive to dimethenamid, S-metolachlor, and pyroxasulfone compared to annual ryegrass, but similar sensitivities were observed for acetochlor. These results suggest that relative differences in sensitivity to chloroacetamide and pyrazole herbicides could be exploited when designing cover crop mixtures for interseeding. It is imperative, however, to use these findings in conjunction with field-based observations of cover crop injury potential in interseeded systems.

Evaluation of cover crops for reducing Heterodera glycines populations in microplot experiments

Summary Soybean cyst nematode (SCN; Heterodera glycines) is a major yield-reducing pathogen of soybean worldwide. Microplot experiments were conducted to evaluate ten cover crops for their effects on two SCN populations (SCN103 and SCN2W) collected from North Dakota, USA, soybean fields in 2019 and 2020. Experiments were conducted in a randomised complete block design using naturally infested field soil. A susceptible soybean ‘Barnes’ and non-planted natural soil (fallow) were used as controls. Plants were grown in outdoor conditions for 75 days before soil samples were collected. SCN eggs and juveniles were extracted from the soil samples to determine final population, population reduction and suppression. Soybean had significantly greater final population densities than all the cover crops and fallow. All cover crops and fallow reduced the initial densities of both SCN populations. All the cover crops, except chickling vetch ‘Pulse’, had lower final population densities than fallow and suppressed the SCN populations throughout the experiments. Sunnhemp (cultivar not stated; CNS), oilseed radish ‘Concorde’ and ‘Control’, and daikon radish ‘Eco-Till’ significantly reduced the SCN103 population compared to fallow. Sunnhemp, alfalfa ‘Bullseye’, and daikon radish had significant population reductions of SCN2W than fallow. Sunnhemp was found to have the greatest reductions in SCN populations ranging from 55 to 86% compared to the initial densities. This study demonstrated cover crop species/cultivars with the ability to reduce SCN populations in outdoor conditions, and the findings indicate that they could be utilised in infested fields to manage SCN.

Effects of cover crops on soil moisture dynamics of a corn cropping system

Climate change induced rainfall patterns have increased environmental extremities such as severe droughts and floods which can affect volumetric soil moisture content (θ), thus food security. Integrating cover crops (CC) with cropping systems can help mitigate these extreme conditions and improve soil water availability. The objective of this study was to evaluate the CC effects on the θ of a corn (Zea mays L.) cropping system. The study was conducted at the USDA Elsberry Plant Material Center, Missouri, USA, with three treatments: no-till cover crop (NC), conventional till no cover crop (CN), and no-till no cover crop (NN). Cereal rye (Secale cereale L.), crimson clover (Trifolium incarnatum L.), and daikon radish (Raphanus sativus L. var. Longipinnatus) CC mixture was established in the NC treatment in 2019 (first CC establishment). Spectrum Technologies Water Scout SM100 soil moisture sensors installed at 5-, 10-, 20- and 40-cm soil depths monitored θ in 15 min intervals throughout the study period. Numerically and significantly greater θ values were observed in the CN treatment than NC and NN at the first three depths during most of the study period. The NC treatment maintained higher θ than NN at all the studied depths during growing periods and were significantly different during some weeks. Results indicate that long-term use of CC can improve soil moisture dynamics of corn cropping systems through improved soil organic matter and would be a viable solution in soil moisture conservation and improving soil security.

Assessing Direct and Residual Effects of Cover Crops on the Soybean Cyst Nematode, Heterodera glycines.

Greenhouse experiments were conducted to determine if cover crops directly decrease population densities of the soybean cyst nematode (SCN), Heterodera glycines, and/or have residual effects on reproduction of the nematode on soybean (Glycine max). Population densities of SCN were not significantly decreased by nine cover crop plants or three cover crop mixes compared with a non-planted soil control in a repeated 60-day-long greenhouse experiment. When susceptible soybeans were grown in the soils after cover crop growth, fewer SCN females formed after three annual ryegrass (Lolium multiflorum) cultivars (Bounty, King, and RootMax), the Daikon radish (Raphanus sativus var. longipinnatus) cultivar CCS779, Kodiak mustard (Brassica juncea), and a mix containing cereal rye, crimson clover (Trifolium incarnatum), plus Daikon radish (cultivars not stated) compared with following the non-planted control. In another repeated experiment, cover crops were grown for 56 days in SCN-infested soil in the greenhouse then exposed to Iowa winter conditions for 28 days to simulate winter termination of the plants. One treatment, a cover crop mix containing 'Bounty' annual ryegrass plus 'Enricher' Daikon radish, had a decrease in SCN population density greater than the non-planted control at the end of the experiment. Significantly fewer SCN females formed on soybeans grown after several cover crops, including the three annual ryegrass cultivars that had the suppressive residual effects in the first experiment. In summary, there were no cover crop treatments that consistently decreased SCN population densities across experiments, and only one cover crop treatment in one experiment significantly reduced SCN population densities more than a non-planted soil control. However, there was a somewhat consistent, adverse, residual effect of cover crops on reproduction of SCN on susceptible soybeans after growth of multiple cover crops.

Phytotoxic effect of sub-3-nm crystalline ceria nanoparticles on the hydroponic growth of Daikon radish microgreens.

Cerium oxide nanoparticles (ceria NPs) have been widely used in many industrial applications. They have been proposed as a potential remedy for reducing oxidative stress in biological systems. General concerns over the toxicity of engineered ceria NPs have led to studies of their phytotoxicity in plants. Most of these plant growth studies were conducted in soil using grain crops and commercial ceria NPs of sizes from 6 nm to 100's nm. In this paper, we report our evaluation of the phytotoxicity and uptake of sub-3-nm crystalline ceria NPs by exposing Daikon radish (Raphanus sativus var. longipinnatus) microgreens to these NPs with environmentally relevant concentrations under hydroponic growth conditions. Aqueous suspensions of different concentrations of these ceria NPs (0.1 ppm, 1 ppm, and 10 ppm) were applied to these microgreens for the last 7 days of the 12-day growth period. Our results revealed the uptake of cerium by plant roots and the translocation of cerium to the stems and the cotyledons (seed leaves). The accumulation of cerium was found to be maximum at the roots, followed by the cotyledons and the stems of the plants. Even at the lowest concentration (0.1 ppm) of the sub-3-nm ceria NPs, the accumulation of cerium at the roots significantly stunted the root growth. However, these NP treatments did not show significant changes to the distributions of macro-minerals (Mg, K, and Ca) and micro-minerals (Zn and Cu) in the microgreens at the end of the 12-day growth period. The phytotoxic effect of sub-3-nm crystalline ceria nanoparticles on the hydroponic growth of Daikon radish microgreens was studied. The cerium uptake by the plant and its effect on the bioavailability of major macro-minerals and micro-minerals within the plant were examined.

The biological sink of atmospheric H2 is more sensitive to spatial variation of microbial diversity than N2O and CO2 emissions in a winter cover crop field trial

The integration of winter cover crop (WCC) in culture rotations promotes multiple ecosystem services, but concomitant microbial diversity and functioning responses in soil have received less attention. A field trial was established to test the hypothesis that enhanced crop diversity with the integration of WCC in a conventional maize-soy rotation promotes microbial diversity and the biological sink of H2 in soil, while reducing N2O emissions to the atmosphere. Vicia villosa (hairy vetch), Avena sativa (oat), and Raphanus sativus (Daikon radish) were cultivated alone or in combinations and flux measurements were performed throughout two subsequent growing seasons. Soil acted as a net sink for H2 and as a net source for CO2 and N2O. CO2 flux was the most sensitive to WCC whereas a significant spatial variation was observed for H2 flux with soil uptake rates observed in the most productive area two-fold greater than the baseline level. Sequencing and quantification of taxonomic and functional genes were integrated to explain variation in trace gas fluxes with compositional changes in soil microbial communities. Fungal communities were the most sensitive to WCC, but neither community abundance nor beta diversity were found to be indicative of fluxes. The alpha diversity of taxonomic and functional genes, expressed as the number of effective species, was integrated into composite variables extracted from multivariate analyses. Only the composite variable computed with the inverse Simpson's index displayed a reproducible pattern throughout both growing seasons, with functional genes and bacterial 16S rRNA gene defining the two most contrasting gradients. The composite variable was decoupled from WCC treatment and explained 19–20% spatial variation of H2 fluxes. The coupling of composite alpha diversity metrics derived from multiple genes with soil processes warrants further investigations to implement novel indicators of soil health in response to changing management practices at the local scale.

Soil bacterial community composition following cover crops and corn nitrogen management

AbstractUtilizing cover crops (CC) prior to corn (Zea mays L.) creates opportunities to increase plant diversity and influence soil bacterial communities, but data are scarce when CC are combined with corn N fertilizer management. Field studies were conducted in 2014–2015 and 2015–2016 to evaluate corn N strategies following daikon radish [Raphanus sativus (L.)], forage oat [Avena sativa (L.)], or no CC on soil bacterial community composition. Nitrogen strategies consisted of 179 kg N ha–1 applied pre‐plant incorporated as urea, slowly‐available poultry litter (61 kg N ha–1) plus sidedress (SID) N at V11, starter N (45 kg N ha–1) applied 5 cm beside and 5 cm below the furrow (5 × 5) plus SID at V4, V11, or 50:50 (split) V4 and V11, and a zero N control. Each year, soil bacterial community composition was variably influenced by CC and N management. With excessive May–June rainfall, radish and oat CC residues shaped community structure and membership differently regardless of soil sampling zone (between‐row or in‐row), but these residues influenced operational taxonomic units (OTUs) less under deficit May–June rainfall. Soil disturbance associated with coulter‐injection of V4 SID placement influenced bulk soil community structure between‐rows, whereas in 1 of 2 yr, the 5 × 5 N placement appeared to induce an in‐row corn rhizosphere response resulting in OTU membership differences from other N strategies. Including slowly‐available organic N as part of a well‐balanced fertility program may stabilize the impact of inorganic N fertilizer to soil bacterial communities.

Physicochemical Properties and Antioxidant Potential of Tateishi Kazu Vegetable Soup

Many industrialized areas of the world demand for the nutraceuticals due to rapidly growing health risks linked with higher consumption of processed foods. Tateishi Kazu vegetable soup or miracle soup is widely consumed around the world because of its nutraceutical properties. In the current research, the Tateishi Kazu vegetable soup was made from both organic and nonorganic sources, such as carrot, burdock root, shiitake mushroom, daikon radish, and radish leaves. We analyzed colour, antioxidant properties, cell viability, and mineral and free amino acid contents of both soups. The L∗a∗b and pH values revealed no drastic changes in the colour of the organic soup stored for 96 hours. The essential amino acids were present in higher amounts in an organic soup compared to the nonorganic soup. Similarly, the total mineral contents of the organic soup were higher than the nonorganic soup; however, potassium was the major mineral in both soups. Higher phenolic contents with elevated 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and superoxide dismutase (SOD) activity were noticed in organic soup. Moreover, both soups showed considerable reduction in cell viability of HepG2 cells tested through the MTT assay. From the present study, we concluded that the organic Tateishi Kazu vegetable soup can be of great importance to food industry due to the presence of viable nutrients and pharmacological properties.

Forage Characteristics and Grazing Preference of Cover Crops in Equine Pasture Systems

Cover crops are commonly used to provide environmental benefits and can extend the grazing season, but have not been explored in horse pastures. The objectives of this research were to evaluate forage mass, forage nutrient composition, and preference of annual ryegrass, winter rye, berseem clover, purple top turnip, and daikon radish under horse grazing. Cover crops were seeded in monoculture and mixtures in August 2018 and 2019 as a randomized complete block with four replicates and grazed by four adult horses. Prior to grazing, forages were sampled to determine herbage and root mass and nutrient composition. After grazing, forages were visually assessed for the percentage of removal on a scale of 0 to 100% to estimate preference. Data was analyzed using an analysis of variance and linear regression; significance was set at P ≤ .05. Berseem clover was the lowest producing forage (590 to 1,869 kg ha−1 dry matter; P ≤.001), while minimal differences in herbage mass were observed among the other cover crops. All forages met digestible energy (>2.17 Mcal kg−1) and crude protein (>19%) requirements for idle, adult horses. Berseem clover was most preferred (>73% removal) while turnip and radish were the least preferred (<19% removal; P ≤.001). Winter rye and annual ryegrass in monoculture and when seeded with berseem clover were moderately preferred (20%–68% removal). Placing a priority on preference, berseem clover, annual ryegrass, and winter rye appear to be suitable cover crops to extend the grazing season in horse pastures.