Brassica Carinata Research Articles

Effects of preceding crops and nitrogen fertilizer on the productivity and quality of malting barley in tropical environment

The growing demand for malt has generated interest for improving productivity through sustainable means such as cropping sequences with malting barley along with optimum nitrogen (N) fertilization. Cropping sequence has many benefits for optimum yield and quality, but knowledge of rotational effects of preceding crops on malting barley is still limited. Thus, this study was conducted to determine the effects of legume and non-legume preceding crops, and N fertilization on productivity and quality of malting barley grown the following year in two locations in the southeastern highland of Ethiopia. The experiment was split plot design with six preceding crops (fababean, Ethiopian mustard, potato, linseed, wheat and malting barley) as main plots and four levels of N (0, 18, 36 and 54 kg N ha−1) for the succeeding crop as split plot treatments with 3 replications. Malting barley grown after fababean, Ethiopian mustard and potato exhibited 13–16, 14–34 and 14%, respectively grain yield increments compared to growing malting barley after malting barley. Similarly, application of 36–54 kg N ha−1 gave 4–29 and 3–19% grain yield increments compared to the control (no N) and previous recommendation (18 kg N ha−1), respectively with no detrimental effect on kernel protein concentrations. Seeding malting barley at a rate of 54 kg N ha−1 gave 250–915% increase in economic benefit. Use of break crops other than barley and increasing the rate of N application from 18 to 54 kg ha−1 have been recommended to boost malting barley yield without surpassing the acceptable range of kernel protein concentrations, reduce costs of production, increase profitability and improve soil fertility to enhance long-term sustainability of the cropping system.

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Co-expressing Eranthis hyemalis lysophosphatidic acid acyltransferase 2 and elongase improves two very long chain polyunsaturated fatty acid production in Brassica carinata

Docosadienoic acid (DDA, 22:2–13,16) and docosatrienoic acid (DTA, 22:3–13,16,19) are two very long chain polyunsaturated fatty acids (VLCPUFAs) that are recently shown to possess strong anti-inflammatory and antitumor properties. An ELO type elongase (EhELO1) from wild plant Eranthis hyemalis can synthesize the two fatty acids by sequential elongation of linoleic acid and alpha-linolenic acid, respectively. Seed-specific expression of this gene in oilseed crop Brassica carinata produced a considerable amount of DDA and DTA in transgenic seeds. However, these fatty acids were excluded from the sn-2 position of triacylglycerols (TAGs). To improve the production level and nutrition value of the VLCPUFAs in the transgenic oilseed crop, a cytoplasmic lysophosphatidic acid acyltransferase (EhLPAAT2) for the incorporation of the two fatty acids into the sn-2 position of triacylglycerols was identified from E. hyemalis. RT-PCR analysis showed that it was preferentially expressed in developing seeds where EhELO1 was exclusively expressed in E. hyemalis. Seed specific expression of EhLPAAT2 along with EhELO1 in B. carinata resulted in the effective incorporation of DDA and DTA at the sn-2 position of TAGs, thereby increasing the total amount of DDA and DTA in transgenic seeds. To our knowledge, this is the first plant LPAAT that can incorporate VLCPUFAs into TAGs. Improved production of DDA and DTA in the oilseed crop using EhLPAAT2 and EhELO1 provides a real commercial opportunity for high value agriculture products for nutraceutical uses.

Emergence patterns of winter and summer annual weeds in Ethiopian mustard (Brassica carinata) cropping system

Abstract Ethiopian mustard (Brassica carinata A. Braun) is a biofuel crop recently introduced in the southeastern United States. For this crop to be successful, integrated weed management strategies that complement its rotation with summer cash crops must be developed. The objectives of this research were to evaluate the effect of previous season summer crops on winter weed emergence patterns during Ethiopian mustard growing season and to assess the impact of planting Ethiopian mustard on the emergence patterns of summer weed species. Gompertz models were fit to winter and summer weed emergence patterns. All models represented more than 80% of the variation, with root mean-square error values less than 0.20. The emergence pattern for winter weed species was best described using growing degree-day accumulation, and this model can be utilized for implementing weed control strategies at the critical Ethiopian mustard growth stages. The results also showed that summer weeds can emerge during the winter in northern Florida but do not survive frost damage, which might create off-season seedbank reductions before the summer crop growing season.

Effects of Cover Crops on Population Reduction of Soybean Cyst Nematode (Heterodera glycines).

Microplot experiments were conducted to evaluate the effects of cover crops on population reduction of a major soybean pest, soybean cyst nematode (SCN; Heterodera glycines Ichinohe) in 2016 and 2017. Ten crop species, including annual ryegrass (Lolium multiflorum L.), Austrian winter pea (Pisum sativum L. subsp. arvense), carinata (Brassica carinata A. Braun), faba bean (Vicia faba Roth), foxtail millet (Setaria italica (L.) P. Beauvois), daikon radish (Raphanus sativus L.), red clover (Trifolium pratense L.), sweetclover (Melilotus officinalis L.), turnip (Brassica rapa subsp. rapa L.), and winter rye (Secale cereale L.), were planted along with susceptible soybean (Glycine max (L.) Merr. 'Barnes') in soil naturally infested with each of two SCN populations (SCN103 and SCN2W) from two North Dakota soybean fields. Crops were grown in large plastic pots for 75 days in an outdoor environment (microplot). Soil samples were collected from each pot for nematode extraction and SCN eggs were counted to determine the final SCN egg density. The population reduction was determined for each crop and nonplanted natural soil (fallow). All of the tested crops and nonplanted natural soil had significantly (P < 0.0001) lower final population densities compared with susceptible soybean (Barnes). Also, a significant difference (P < 0.0001) was observed between the SCN population suppressions caused by cover crops versus the fallow treatment. All cover crops except Austrian winter pea, carinata, faba bean, and foxtail millet had consistently lower SCN egg numbers than in fallow in both years of the experiments. The average population reductions of SCN by the cover crops ranged from 44 to 67% in comparison with the initial population density, while the fallow had natural reductions from 4 to 24%. Annual ryegrass and daikon radish reduced SCN egg numbers to a greater extent than the other cover crops, with an average of 65 and 67% reduction of initial population density, respectively, from 2 years. The results suggested that cover crops reduced the SCN populations in external microplot conditions, and their use has great potential for improving SCN management in infested fields.

Plants Specifically Modulate the Microbiome of Root-Lesion Nematodes in the Rhizosphere, Affecting Their Fitness.

Plant-parasitic nematodes are a major constraint on agricultural production. They significantly impede crop yield. To complete their parasitism, they need to locate, disguise, and interact with plant signals exuded in the rhizosphere of the host plant. A specific subset of the soil microbiome can attach to the surface of nematodes in a specific manner. We hypothesized that host plants recruit species of microbes as helpers against attacking nematode species, and that these helpers differ among plant species. We investigated to what extend the attached microbial species are determined by plant species, their root exudates, and how these microbes affect nematodes. We conditioned the soil microbiome in the rhizosphere of different plant species, then employed culture-independent and culture-dependent methods to study microbial attachment to the cuticle of the phytonematode Pratylenchus penetrans. Community fingerprints of nematode-attached fungi and bacteria showed that the plant species govern the microbiome associated with the nematode cuticle. Bacteria isolated from the cuticle belonged to Actinobacteria, Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Sphingobacteria, and Firmicutes. The isolates Microbacterium sp. i.14, Lysobacter capsici i.17, and Alcaligenes sp. i.37 showed the highest attachment rates to the cuticle. The isolates Bacillus cereus i.24 and L. capsici i.17 significantly antagonized P. penetrans after attachment. Significantly more bacteria attached to P. penetrans in microbiome suspensions from bulk soil or oat rhizosphere compared to Ethiopian mustard rhizosphere. However, the latter caused a better suppression of the nematode. Conditioning the cuticle of P. penetrans with root exudates significantly decreased the number of Microbacterium sp. i.14 attaching to the cuticle, suggesting induced changes of the cuticle structure. These findings will lead to a more knowledge-driven exploitation of microbial antagonists of plant-parasitic nematodes for plant protection.

The Impacts of Micronutrient Fertility on the Mineral Uptake and Growth of Brassica carinata

Many abiotic factors impact the yield and growth of Brassica carinata (commonly referred to as carinata or Ethiopian mustard). Very little is known about carinata and how mineral nutrients impact its growth, and more specifically, the sufficiency values for fertility over the plant’s growth cycle and life stages. This study explored the impacts that plant nutrients, specifically micronutrients, can have on the growth and development of carinata over its distinct life stages (rosette, bolting, flowering, and pod set). Plants were grown under varying micronutrient concentrations (0, 25, 50, 75, 87.5, and 100%) of a modified Hoagland’s solution. Data were collected on plant height, canopy diameter, leaf tissue mineral nutrient concentrations, and biomass. The results demonstrated that micronutrient fertility has profound impacts on the production of Brassica carinata during different life stages. Boron (B) exclusion had the greatest impact on the growth and reproduction of Brassica carinata, with the death of the apical meristem that resulted in a lack of siliques or seeds at the lowest rate. Optimal relative elemental leaf tissue concentrations varied among micronutrient fertility concentrations and life stages. Certain elements exhibited linear increases in nutrient leaf tissue accumulation as solution concentration increased without reaching a maximum concentration during specific life stages. Other life stages and/or elements produced distinct plateau leaf tissue mineral concentrations despite increasing fertility treatment concentrations such as B in the rosette stage (47.2–50.0 mg·kg−1), copper (Cu) (bolting stage at 6.62–7.57 mg·kg−1), zinc (Zn) (bolting stage at 27.47–39.87 and flowering at 33.98–43.50 mg·kg−1), molybdenum (Mo) (flowering stage at 2.42–3.23 mg·kg−1), and manganese (Mn) (bolting stage at 117.03–161.63 mg·kg−1). This work demonstrates that Brassica carinata has different fertility demands and will accumulate differing leaf tissue concentrations during its life stages. This work serves as a baseline for further uptake and portioning work for Brassica carinata.

Steam pressure induced changes in carbohydrate molecular structures, chemical profile and in vitro fermentation characteristics of seeds from new Brassica carinata lines

Recently, new lines of Brassica carinata with high oil and erucic acid contents in their seeds have been developed for bio-fuel industry. The co-product after oil extraction, carinata meal, is high in crude protein (CP) and low in neutral detergent fiber (NDF) content, and can be used as feed ingredient in ruminant rations after processing such as steam pressure heating. However, the effects of steam pressure on the molecular structures, nutritional and metabolic characteristics of carinata meal produced from newly developed Brassica carinata lines has not been investigated. The objectives of this study were to investigate effects of steam pressure heating, autoclaving, at 121 °C for 0, 30, 60 and 90 min on changes in carbohydrate chemical profile, the Cornell Net Carbohydrate and Protein System (CNCPS) carbohydrate subfractions, ruminal fermentation characteristics and gas production (GP; in vitro) in relation to changes in carbohydrate molecular structure, of the newly develop Brassica carinata seeds. Except total carbohydrates, steam pressure heating altered (P < 0.05) all measured carbohydrate chemical components and CNCPS subfractions. The contents of neutral detergent fiber (aNDF), acid detergent fiber (ADF), acid detergent lignin (ADL), cellulose and soluble fiber (subfraction CB2) increased (P < 0.01) with increasing duration of steam pressure heating from 0 to 90 min in linear fashions. Whereas, the contents of sugar (fraction CA4), non-fibrous carbohydrate (NFC) and digestible fiber (fraction CB3) decreased (P < 0.05) linearly. Compared to raw seeds, the indigestible fiber subfraction increased (P = 0.001) with steam pressure heating (30−90 min). On average, the heated seeds had lower (P < 0.05) values of theoretically maximum GP (44 vs. 56.5 mL), dry matter digestibility (644 vs 559 g/ kg), and crude protein digestibility (886 vs 645 g/kg) after 48 h fermentation. The largest decrease in theoretically maximum GP (31 %), dry matter digestibility (57 %) and crude protein digestibility (35 %) after 48 h incubation was recorded for the 60 min steam pressure heating. As compared to raw seeds, the heated seeds produced higher (P = 0.01) content of acetate and lower (P ≤ 0.01) content of ammonia, isobutyrate and valerate after 24 h of fermentation. These heat-induced changes in chemical profile and ruminal fermentation characteristics were strongly correlated with the changes in inherent molecular structures of carbohydrates, particularly, with peak areas of structural carbohydrates and cellulosic compounds.

Stable, fertile lines produced by hybridization between allotetraploids Brassica juncea (AABB) and Brassica carinata (BBCC) have merged the A and C genomes.

Many flowering plant taxa contain allopolyploids that share one or more genomes in common. In the Brassica genus, crop species Brassica juncea and Brassica carinata share the B genome, with 2n=AABB and 2n=BBCC genome complements, respectively. Hybridization results in 2n=BBAC hybrids, but the fate of these hybrids over generations of self-pollination has never been reported. We produced and characterized B.juncea×B. carinata (2n=BBAC) interspecific hybrids over six generations of self-pollination under selection for high fertility using a combination of genotyping, fertility phenotyping, and cytogenetics techniques. Meiotic pairing behaviour improved from 68% bivalents in the F1 to 98% in the S5 /S6 generations, and initially low hybrid fertility also increased to parent species levels. The S5 /S6 hybrids contained an intact B genome (16 chromosomes) plus a new, stable A/C genome (18-20 chromosomes) resulting from recombination and restructuring of A and C-genome chromosomes. Our results provide the first experimental evidence that two genomes can come together to form a new, restructured genome in hybridization events between two allotetraploid species that share a common genome. This mechanism should be considered in interpreting phylogenies in taxa with multiple allopolyploid species.

Phytotherapy and food applications from Brassica genus.

Plants of the genus Brassica occupy the top place among vegetables in the world. This genus, which contains a group of six related species of a global economic significance, three of which are diploid: Brassica nigra (L.) K. Koch, Brassica oleracea L., and Brassica rapa L. and three are amphidiploid species: Brassica carinata A. Braun, Brassica juncea (L.) Czern., and Brassica napus L. These varieties are divided into oily, fodder, spice, and vegetable based on their morphological structure, chemical composition, and usefulness of plant organs. The present review provides information about habitat, phytochemical composition, and the bioactive potential of Brassica plants, mainly antioxidant, antimicrobial, anticancer activities, and clinical studies in human. Brassica vegetables are of great economic importance around the world. At present, Brassica plants are grown together with cereals and form the basis of global food supplies. They are distinguished by high nutritional properties from other vegetable plants, such as low fat and protein content and high value of vitamins, fibers along with minerals. In addition, they possess several phenolic compounds and have a unique type of compounds namely glucosinolates that differentiate these crops from other vegetables. These compounds are also responsible for numerous biological activities to the genus Brassica as described in this review.

A candidate gene-based association study of introgressed pod shatter resistance in Brassica napus

Yield losses at maturity due to unsynchronized pod shattering remain a major rapeseed breeding challenge. Variation for shatter resistance in the germplasm collections is inadequate for breeding manipulations. We have recently transferred resistance to pod shattering from Brassica carinata to Brassica napus . Introgression lines (ILs) were phenotyped for shatter resistance using the pendulum machine. Introgressive breeding was successful in enhancing rupture energy in the ILs, which varied from 1.8 to 7.2 mJ for E1 and 2.7 to 6.5 mJ for E2 while the corresponding values for natural B. napus ranged from 2.2 - 3.5 mJ (E1) and 2.2 - 4.3 mJ (E2) respectively. B. carinata had an average rupture energy of 6.3 mJ (pooled over environments). On the basis of data averaged over two environments, I2 (6.3 mJ), I3 (5.2 mJ), I8 (5.6 mJ), I22 (5.1 mJ), I32 (5.2 mJ) and I41 (5.2 mJ) appeared very promising as germplasm resources for future breeding. Significant marker trait association between candidate gene NAC and rupture energy explained 19% of variation for the trait. NDEH 3 also appeared to be associated with rupture energy under E1. These polymorphisms represent promising candidates for the development of molecular markers for marker-assisted deployment of introgressed shatter resistance.

Nitrogen and sulfur fertilizers effects on growth and yield of Brassica carinata in South Dakota

AbstractCarinata (Brassica carinata A. Braun), a non‐food oilseed and an alternative biofuel feedstock, has received attention for its potential as a low‐input option for production in the semi‐arid regions of the Northern Great Plains (NGP). This study was conducted to (a) determine the economic optimum N and S fertilization rates and (b) determine the interactive effects of N and S fertilization on seed yield and agronomic traits in carinata. The field experiment conducted in 2017 and 2018 at Brookings, SD, had four N rates (56, 84, 112, and 140 kg N ha−1) and three S rates (0, 22, and 45 kg S ha−1). Increasing N rate increased seed and oil yield each peaking at 112 kg N ha−1 in both years. Applying S fertilizer increased seed and oil yield and oil concentration over the control but with the two S rates performing similar in both years. In the absence of S application, seed yield was reduced irrespective of N rate indicating that S is critical to obtain a positive response to N fertilizer. Economically optimal N rate ranged from 47 to 93 kg N ha−1 whereas economic optimum S rate ranged from 20 to 26 kg S ha−1. The economic optimum yield ranged from 1.0 Mg ha−1 to 1.5 Mg ha−1. These findings suggest that carinata seed yield and agronomic trait response to N fertilization can vary depending on S availability in the soil.

Brassica carinata: Biology and agronomy as a biofuel crop

AbstractThe environmental consequences of using nonrenewable fossil fuels have motivated a global quest for sustainable alternatives from renewable sources. Carinata has been developed as a low carbon intensity, non‐food oilseed biomolecular platform to produce advanced drop‐in renewable fuels, meal, and co‐products. The crop is widely adaptable to grow in the humid subtropical and humid continental climatic regions of Asia, Africa, North America, South America, Europe, and Australia as a spring or winter crop. Carinata is heat tolerant, resistant to diseases and seed shattering with lower water‐use requirements than other oilseed brassicas. Adopting carinata in double‐cropping systems would require continuing research to integrate crop biology with agronomy, to understand growth and development and its interaction with agricultural inputs and management. Site‐specific best management agronomic practices and crop improvement research to develop frost‐tolerant, early‐maturing, nutrient use‐efficient, and high yielding varieties with desirable oil content and fatty acid profile will enhance the crop's adaptability and economic viability. The exploitation of intra‐ and interspecific and intra‐ and intergeneric diversity will further enhance carinata productivity and resistance to biotic and abiotic stresses. This review attempts to present a comprehensive description of carinata's biology, beginning with its origin and current state of distribution, availability of genetic and genomic resources, and a discussion of its morphology, phenology, and reproduction. A detailed analysis of the agronomy of the crop, including planting and germination and management practices, is presented in the context of crop growth and development. This will facilitate global adoption, sustainable production, and commercialization of carinata as a dedicated biofuel oilseed crop in diverse cropping systems and growing regions of the world, including the Southeast United States.

Effect of Previous Crop Roots on Soil Compaction in 2 Yr Rotations under a No-Tillage System

Compacted soils affect global crop productivity and environmental quality. A field study was conducted from 2014 to 2020 in the northern Great Plains, USA, to evaluate the effect of various rooting systems on soil compaction in 2 yr rotations of camelina (Camelina sativa L.), carinata (Brassica carinata A.) and a cover crop mix planted in place of fallow with durum (Triticum durum D.). The study was designed as a randomized complete block with three replications in a no-tillage system. The soil was classified as Dooley sandy loam (fine-loamy, mixed, superactive, frigid Typic Argiustolls) derived from glacial till parent material. Three measurements of soil penetration resistance (PR) were taken with a penetrometer to a depth of 0–30 cm within each plot. Soil moisture contents were determined using a TDR sensor at the time of PR measurements. Both measurements were monitored prior to planting in spring and after harvest. Initial PR results from spring 2014 showed that all plots had an average of 2.244 MPa between the 8–20 cm depth, due to a history of tillage and wheel traffic caused by various field activities. Covariance analysis indicated that soil PR was not significantly affected by crop type and moisture content. After one cycle of the 2 yr rotation, the 2016 measurements indicated that the compacted layer existed at the same initial depths. However, after two and three cycles, soil PR values were reduced to 1.480, 1.812, 1.775, 1.645 MPa in spring 2018 and 1.568, 1.581, 1.476, 1.458 MPa in 2020 under camelina, carinata, cover crop mix, and durum treatments, respectively. These findings indicate that previous cover crop roots could effectively improve soil compaction by penetrating the compacted layer, decompose over time and form voids and root channels. Although these results are novel and significant, further research is needed on different soils and under cover crops with different root systems to support our findings prior to making any conclusion.

Biochemical conversion of Brassicacarinata biomass to organic acids

AbstractThe economics of the inedible oilseed crop Brassica carinata as a source of renewable fuels can be enhanced by converting its cellulosic biomass to value‐added chemicals, such as organic acids. We investigated the biochemical conversion of carinata biomass to propionic acid by first pretreating the carinata meal (CM), which is obtained after extraction of the oil from carinata seeds, with concentrated phosphoric acid to remove hemicellulose and gain access to the cellulose constituent of the meal. We then subjected the pretreated meal to enzymatic hydrolysis with cellulase enzyme to depolymerize cellulose to glucose. The overall conversion of carinata cellulose to glucose was 85%, which is promising. Finally, the recovered glucose was successfully fermented primarily to propionic acid using the bacterium Propionibacterium freudenreichii with a yield of 0.57 g of produced propionic acid per gram of consumed cellulosic glucose. The biobased propionic acid and other co‐produced organic acids can serve as renewable building blocks for manufacturing industrial chemicals and food preservatives replacing fossil‐derived organic acids. Hence, CM constitutes a renewable source of fermentable carbohydrates potentially improving the economics and sustainability of the carinata value chain.

Responses of soil surface greenhouse gas emissions to nitrogen and sulfur fertilizer rates to Brassica carinata grown as a bio‐jet fuel

AbstractCarinata (Brassica carinata A. Braun), a non‐food oilseed crop and an alternative bio‐jet fuel feedstock, has received attention for its potential as a low‐input option for production in the semi‐arid region of the Northern Great Plains of the United States. Research addressing the impacts of nitrogen (N) and sulfur (S) fertilizers on soils and greenhouse gas (GHG; CO2, N2O, and CH4) emissions from carinata production are limited. Thus, objective of this study was to evaluate the impact of different rates of N and S fertilizers applied to carinata on soil properties and GHG emissions. Field experiments were conducted in 2017 and 2018 to assess the response of carinata to four N (56, 84, 112, and 140 kg N ha−1) and three S (0, 22, and 45 kg S ha−1) rates. Soil samples were collected at crop harvest to measure soil properties; however, soil surface GHG fluxes were measured during 2017 and 2018 growing seasons using static chamber method. Data showed that application of N fertilizer increased soil EC, soil organic carbon (SOC), stable C, and labile N. However, sulfur fertilizer decreased SOC, labile N, and soil inorganic N contents. Results from GHG fluxes showed that higher rates of N fertilizer application increased the soil CO2 and N2O emissions, whereas the S fertilizer did not impact these fluxes. This study concludes that S and N fertilizers application to carinata crop affected soil properties, and higher rates of N fertilizer increased the GHG emissions. Therefore, N fertilizer application rate needs to be optimized to mitigate GHG emission for carinata production.

Occurrence of arthropod pests associated with Brassica carinata and impact of defoliation on yield

AbstractBrassica carinata has the potential to become an economical biofuel winter crop in the Southeast U.S. An IPM program is needed to provide management recommendations for B. carinata in the region. This study serves as the first steps in the developing IPM tactics documenting pest occurrence, pest position within the canopy, and the impact of defoliation on B. carinata yield. The study was performed in Jay, FL, during the 2017–2018 and 2018–2019 winter/spring crop seasons. Pest species in B. carinata were documented by plant inspection within 16 genotypes of B. carinata, and the presence of insect pests in three canopy zones (upper, medium, and lower canopy) was documented. The defoliation impact on B. carinata was evaluated by artificial defoliation. Five levels of defoliation (2017–2018 crop season: 0%, 5%, 25%, 50%, and 100%; 2018–2019 crop season: 0%, 50%, 75%, 90%, and 100%) were artificially applied during vegetative, flowering, and pod formation stages of the commercial cultivar “Avanza64.” During the 2018–2019 crop season, two experiments were performed, a one‐time defoliation event and continuous defoliation. The plants were hand harvested and the average number of pods per plants, seeds per pod, thousand seed weight, and yield were estimated and correlated with defoliation levels. Results indicated the following species of pests associated with B. carinata: Microtheca ochroloma Stål (Coleoptera: Chrysomelidae), Plutela xylostella larvae, Pieris rapae L. (Lepidoptera: Pieridae), Diabrotica undecimpunctata Barber (Coleoptera: Chrysomelidae), Lipaphis pseudobrassicae Davis (Hemiptera: Aphididae), Leptoglossus phyllopus L. (Hemiptera: Coreidae), and Chloridea virescens F. (Lepidoptera: Noctuidae). The insect distribution within the plant canopy was not uniform. Different levels of artificial B. carinata defoliation did not affect seed weight, the number of seeds per pod, or the oil content of the seeds. The number of pods per plants and estimated yield were negatively impacted by defoliation during the vegetative and flowering stages.

Tillage system and seeding rate effects on the performance of Brassica carinata

AbstractBrassica carinata, a nonfood oilseed crop, is used to produce renewable fuels because of its high oil content and favorable fatty acid profile. Production in the southeastern United States is relatively new, and information on agronomic management practices to optimize growth and yield is limited. Since optimal seeding rate may depend on the land preparation method for this small‐seeded crop, a study was conducted to evaluate the effect of tillage system (conventional, no‐till, broadcast‐disc, and ripper‐roller) and seeding rate (1.12, 5.60, 10.09, and 14.57 kg seed ha−1) on the performance of B. carinata. A randomized complete block design with a strip‐plot restriction on randomization and four replications was implemented in Headland, AL, Jay, FL, and Quincy, FL, over five site‐years during the 2017–2018 and 2018–2019 growing seasons. Data were collected on soil residue cover; plant population; soil penetrometer resistance and moisture; biomass (including carbon and nitrogen); stalk diameter; yield and yield components; seed oil, protein, and glucosinolates concentration; and oil composition. Soil penetrometer resistance was significantly affected by tillage system, with the ripper‐roller consistently having the lowest penetration resistance values across all site‐years. Ripper‐roller tillage had the highest oil content and lowest protein and glucosinolate contents. Yield response to tillage system was variable. Among seeding rate treatments, yield was lowest at 1.12 kg seed ha−1 and similar among 5.60, 10.09, and 14.57 kg seed ha−1 at all site‐years. There was no tillage by seeding rate interaction for yield. Results indicate that among seeding rate treatments used, 5.6 kg seed ha−1 rate was optimal at all site‐years regardless of land preparation method and is thus the recommended seeding rate for commercial carinata production in the Southeastern United States.

Production of green transportation fuels from Brassica carinata oil: A comparative study of noble and transition metal catalysts

Herein, we present the production of jet and diesel range hydrocarbons from non-edible hexane-extracted Brassica carinata oil. The influence of four heterogeneous catalysts (two noble metal catalysts: Pd/C and Ru/C, and two transition metal catalysts: Ni/C and Ni/SiO2-Al2O3) was investigated at 400 °C. The catalysts were characterized using XRD, Raman spectroscopy, TEM, SEM, TGA, TG-TPR, and BET specific surface area and pore size analyzer. The upgrading experiments consisted of three different approaches: 1) single-step cracking (1-C), 2) single-step simultaneous cracking, and hydrotreatment (1-C·H), and 3) a two-step process of cracking followed by hydrotreatment (2-C·H). Reaction products were characterized using different instruments and metrics: GC-FID, GC–MS, simulated distillation, CHNS-O elemental analyzer, viscometer, higher heating value (HHV), and total acid number (TAN). The 2-C·H process produced the highest amounts of desired hydrocarbons. The highest liquid yield of 81% with HHV of 47 MJ/kg was obtained with the use of Ni/SiO2-Al2O3 catalyst. All catalysts appeared to be regenerable after partial deactivation. Model compound studies were performed using erucic acid that accounted for about 40% of carinata oil FFA (free fatty acid) profile. Reaction pathways were proposed according to the chemical analysis of the products.

Brassica carinata genome characterization clarifies U's triangle model of evolution and polyploidy in Brassica.

Ethiopian mustard (Brassica carinata) in the Brassicaceae family possesses many excellent agronomic traits. Here, the high-quality genome sequence of B. carinata is reported. Characterization revealed a genome anchored to 17 chromosomes with a total length of 1.087 Gb and an N50 scaffold length of 60 Mb. Repetitive sequences account for approximately 634 Mb or 58.34% of the B. carinata genome. Notably, 51.91% of 97,149 genes are confined to the terminal 20% of chromosomes as a result of the expansion of repeats in pericentromeric regions. Brassica carinata shares one whole-genome triplication event with the five other species in U's triangle, a classic model of evolution and polyploidy in Brassica. Brassica carinata was deduced to have formed ∼0.047 Mya, which is slightly earlier than B. napus but later than B. juncea. Our analysis indicated that the relationship between the two subgenomes (BcaB and BcaC) is greater than that between other two tetraploid subgenomes (BjuB and BnaC) and their respective diploid parents. RNA-seq datasets and comparative genomic analysis were used to identify several key genes in pathways regulating disease resistance and glucosinolate metabolism. Further analyses revealed that genome triplication and tandem duplication played important roles in the expansion of those genes in Brassica species. With the genome sequencing of B. carinata completed, the genomes of all six Brassica species in U's triangle are now resolved. The data obtained from genome sequencing, transcriptome analysis, and comparative genomic efforts in this study provide valuable insights into the genome evolution of the six Brassica species in U's triangle.