Teaching a microorganism to use a new substrate necessitates constructing a utilization pathway that connects the substrate to a metabolite in central carbon metabolism. The process is not straightforward and fraught with hiccups such as lack of carbon flux to make a firm connection to central carbon metabolism. Ethylene glycol is one promising alternative substrate given its availability as hydrolysis product from polyethylene terephthalate (PET) plastic waste recycling. But, what is lacking thus far is a utilization pathway that could mediate its transformation into a metabolite that could plug into central carbon metabolism and activate cell growth. This write-up attempts to review prior work on developing ethylene glycol as an alternative feedstock for a bioeconomy as well as origins of ethylene glycol role as a sole carbon source for some microorganisms. While focus is inevitably on developing a “plug-in” pathway for connecting ethylene glycol to central carbon metabolism, preliminary work in this endeavor also needs to focus on understanding any possible metabolic deficiency in the chosen microbial chassis that could make substrate utilization metabolic engineering that much tougher.
{"title":"Possibility of teaching Bacillus subtilis ethylene glycol utilization","authors":"Wenfa Ng","doi":"10.2139/ssrn.3814481","DOIUrl":"https://doi.org/10.2139/ssrn.3814481","url":null,"abstract":"Teaching a microorganism to use a new substrate necessitates constructing a utilization pathway that connects the substrate to a metabolite in central carbon metabolism. The process is not straightforward and fraught with hiccups such as lack of carbon flux to make a firm connection to central carbon metabolism. Ethylene glycol is one promising alternative substrate given its availability as hydrolysis product from polyethylene terephthalate (PET) plastic waste recycling. But, what is lacking thus far is a utilization pathway that could mediate its transformation into a metabolite that could plug into central carbon metabolism and activate cell growth. This write-up attempts to review prior work on developing ethylene glycol as an alternative feedstock for a bioeconomy as well as origins of ethylene glycol role as a sole carbon source for some microorganisms. While focus is inevitably on developing a “plug-in” pathway for connecting ethylene glycol to central carbon metabolism, preliminary work in this endeavor also needs to focus on understanding any possible metabolic deficiency in the chosen microbial chassis that could make substrate utilization metabolic engineering that much tougher.","PeriodicalId":8795,"journal":{"name":"Biochemistry eJournal","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84018240","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-30DOI: 10.15587/2519-4852.2020.221078
А. Kovaleva, T. Ilina, A. Raal, A. Osmachko, O. Goryacha, Y. Rozhkovskyi
The aim. The genus Veronica (Veronica L.), family Plantaginaceae Juss. in the flora of Ukraine is represented by 64 species; Veronica chamaedrys L. and Veronica teucrium L. are widespread in the Kharkiv region. Plants are used in folk medicine as expectorants, anti-inflammatory, diaphoretic, anti-allergic, choleretic, antispasmodic, anticonvulsant, diuretic, sedative, wound healing and antibacterial agents. The aim of this work was to study the carboxylic acids of flowers and leaves of Veronica chamaedrys L. and flowers and leaves of Veronica teucrium L. Materials and methods. The objects of the study were flowers and leaves of Veronica chamaedrys L. and Veronica teucrium L., harvested in the flowering phase in 2018 in Kharkiv region, Ukraine. The study of carboxylic acids was performed by chromatography-mass spectrometry on a 6890N MSD/DS Agilent Technologies chromatograph with a 5973N mass spectrometric detector. Identification of acid methyl esters was performed using data from the mass spectrum library NIST 05 and Willey 2007 in combination with programs for the identification of AMDIS and NIST; also compared the retention time with the retention time of standard compounds. Results. In the flowers and leaves of Veronica teucrium L. 35 carboxylic acids were identified, the total content of which is 5.55 % and 2.93 %, respectively. 31 and 32 carboxylic acids were identified in the flowers and leaves of Veronica chamaedrys L., their total content is 5.39 % and 7.45 %, respectively. Conclusions. It is established that the flowers and leaves of Veronica chamaedrys L. are characterized by a higher content of carboxylic acids compared to the flowers and leaves of Veronica teucrium L. As chemotaxonomic markers of flowers and leaves the following compounds can be used: α-furanic acid for Veronica chamaedrys L.; veratric, 4-hydroxybenzylacetic and syringic acids for Veronica teucrium L. The obtained results will be the basis for further chemotaxonomic studies
{"title":"The Study of Carboxylic Acids in Flowers and Leaves of Veronica Chamaedrys L. and Veronica Teucrium L.","authors":"А. Kovaleva, T. Ilina, A. Raal, A. Osmachko, O. Goryacha, Y. Rozhkovskyi","doi":"10.15587/2519-4852.2020.221078","DOIUrl":"https://doi.org/10.15587/2519-4852.2020.221078","url":null,"abstract":"The aim. The genus Veronica (Veronica L.), family Plantaginaceae Juss. in the flora of Ukraine is represented by 64 species; Veronica chamaedrys L. and Veronica teucrium L. are widespread in the Kharkiv region. Plants are used in folk medicine as expectorants, anti-inflammatory, diaphoretic, anti-allergic, choleretic, antispasmodic, anticonvulsant, diuretic, sedative, wound healing and antibacterial agents. The aim of this work was to study the carboxylic acids of flowers and leaves of Veronica chamaedrys L. and flowers and leaves of Veronica teucrium L. Materials and methods. The objects of the study were flowers and leaves of Veronica chamaedrys L. and Veronica teucrium L., harvested in the flowering phase in 2018 in Kharkiv region, Ukraine. The study of carboxylic acids was performed by chromatography-mass spectrometry on a 6890N MSD/DS Agilent Technologies chromatograph with a 5973N mass spectrometric detector. Identification of acid methyl esters was performed using data from the mass spectrum library NIST 05 and Willey 2007 in combination with programs for the identification of AMDIS and NIST; also compared the retention time with the retention time of standard compounds. Results. In the flowers and leaves of Veronica teucrium L. 35 carboxylic acids were identified, the total content of which is 5.55 % and 2.93 %, respectively. 31 and 32 carboxylic acids were identified in the flowers and leaves of Veronica chamaedrys L., their total content is 5.39 % and 7.45 %, respectively. Conclusions. It is established that the flowers and leaves of Veronica chamaedrys L. are characterized by a higher content of carboxylic acids compared to the flowers and leaves of Veronica teucrium L. As chemotaxonomic markers of flowers and leaves the following compounds can be used: α-furanic acid for Veronica chamaedrys L.; veratric, 4-hydroxybenzylacetic and syringic acids for Veronica teucrium L. The obtained results will be the basis for further chemotaxonomic studies","PeriodicalId":8795,"journal":{"name":"Biochemistry eJournal","volume":"29 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78142006","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
N. Kleimeier, A. Eckhardt, P. Schreiner, R. Kaiser
Summary Pyruvic acid represents a key molecule in prebiotic chemistry to form metabolites and amino acids. Without liquid water on the early Earth, endogenous formation of pyruvic acid is unlikely, and an exogenous delivery constitutes an appealing alternative. However, despite the detection of more than 200 molecules in space, pyruvic acid is elusive. Here, we describe its formation by barrierless recombination of hydroxycarbonyl (HOCO⋅) and acetyl (CH3CO⋅) radicals in ices of acetaldehyde (CH3CHO) and carbon dioxide (CO2) modeling interstellar conditions driven by cosmic rays. Exploiting isotopically labeled ices and photoionization reflectron time-of-flight mass spectrometry, the reaction products were selectively photoionized in the temperature-programmed desorption phase and isomers discriminated based on their ionization energies. This reveals a key reaction pathway for pyruvic acid synthesis through non-equilibrium reactions in interstellar cold molecular clouds and star-forming regions, thus offering a unique entry point to abiotic organic synthesis in deep space.
{"title":"Interstellar Formation of Biorelevant Pyruvic Acid (CH 3COCOOH)","authors":"N. Kleimeier, A. Eckhardt, P. Schreiner, R. Kaiser","doi":"10.2139/ssrn.3652328","DOIUrl":"https://doi.org/10.2139/ssrn.3652328","url":null,"abstract":"Summary Pyruvic acid represents a key molecule in prebiotic chemistry to form metabolites and amino acids. Without liquid water on the early Earth, endogenous formation of pyruvic acid is unlikely, and an exogenous delivery constitutes an appealing alternative. However, despite the detection of more than 200 molecules in space, pyruvic acid is elusive. Here, we describe its formation by barrierless recombination of hydroxycarbonyl (HOCO⋅) and acetyl (CH3CO⋅) radicals in ices of acetaldehyde (CH3CHO) and carbon dioxide (CO2) modeling interstellar conditions driven by cosmic rays. Exploiting isotopically labeled ices and photoionization reflectron time-of-flight mass spectrometry, the reaction products were selectively photoionized in the temperature-programmed desorption phase and isomers discriminated based on their ionization energies. This reveals a key reaction pathway for pyruvic acid synthesis through non-equilibrium reactions in interstellar cold molecular clouds and star-forming regions, thus offering a unique entry point to abiotic organic synthesis in deep space.","PeriodicalId":8795,"journal":{"name":"Biochemistry eJournal","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79455317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kristýna Gunár, L. Kotrchová, M. Filipová, Tereza Krunclová, R. Pola, E. Randárová, T. Etrych, O. Janoušková
Exosomes are endosomally-derived vesicles. Their composition is significantly affected by physiological state of the donor cells and can reflect changes in the cell microenvironment as well as of the whole body. Exosomes can manipulate local and systemic environment to influence cancer progression and dissemination and also modulate immune response. Moreover, exosomes have been investigated as possible transmission nanocarriers for therapeutics. In this study, exosome loading was achieved by incubation of free doxorubicin (DOX) and DOX bound to N -(2-hydroxypropyl) methacrylamide (HPMA)-based copolymers (pHPMA) with an adherent human breast adenocarcinoma cell line and its derived spheroids. Both free and p(HPMA)-bound DOX were successfully loaded into exosomes with different loading efficiencies. Spheroids secreted significantly more exosomes than adherent cells. These exosomes differed in abundance of their exosomal markers. The adherent cell line showed a decreased viability after treatment with free DOX or pHPMA bound-DOX-loaded exosomes, confirming the successful transmission of both, free cancerostatics and polymer bound cancerostatics by exosomes. To our knowledge, this is the first proof of pHPMA-drug conjugates secretion by extracellular vesicles, providing a new perspective on the transmission of drug/polymeric drugs in tumor tissue via exosomes. Interestingly, results obtained within the manuscript contribute to the explanation of high therapeutic activity of pH-sensitive polymer-DOX conjugates, which we suppose, is based on the exosome-based cell-to-cell delivery within the tumor tissue after the passive accumulation of the polymer-drug system.
{"title":"The Transmission and Toxicity of Phpma Copolymer-Bound Doxorubicin Containing Exosomes Derived from Adherent Two-Dimensional Human Breast Adenocarcinoma Cell Line and Three-Dimensional Spheroids","authors":"Kristýna Gunár, L. Kotrchová, M. Filipová, Tereza Krunclová, R. Pola, E. Randárová, T. Etrych, O. Janoušková","doi":"10.2139/ssrn.3692012","DOIUrl":"https://doi.org/10.2139/ssrn.3692012","url":null,"abstract":"Exosomes are endosomally-derived vesicles. Their composition is significantly affected by physiological state of the donor cells and can reflect changes in the cell microenvironment as well as of the whole body. Exosomes can manipulate local and systemic environment to influence cancer progression and dissemination and also modulate immune response. Moreover, exosomes have been investigated as possible transmission nanocarriers for therapeutics. In this study, exosome loading was achieved by incubation of free doxorubicin (DOX) and DOX bound to N -(2-hydroxypropyl) methacrylamide (HPMA)-based copolymers (pHPMA) with an adherent human breast adenocarcinoma cell line and its derived spheroids. Both free and p(HPMA)-bound DOX were successfully loaded into exosomes with different loading efficiencies. Spheroids secreted significantly more exosomes than adherent cells. These exosomes differed in abundance of their exosomal markers. The adherent cell line showed a decreased viability after treatment with free DOX or pHPMA bound-DOX-loaded exosomes, confirming the successful transmission of both, free cancerostatics and polymer bound cancerostatics by exosomes. To our knowledge, this is the first proof of pHPMA-drug conjugates secretion by extracellular vesicles, providing a new perspective on the transmission of drug/polymeric drugs in tumor tissue via exosomes. Interestingly, results obtained within the manuscript contribute to the explanation of high therapeutic activity of pH-sensitive polymer-DOX conjugates, which we suppose, is based on the exosome-based cell-to-cell delivery within the tumor tissue after the passive accumulation of the polymer-drug system.","PeriodicalId":8795,"journal":{"name":"Biochemistry eJournal","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83790103","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yan Ai, Yuxiou You, Facai Wei, Xiaolin Jiang, Zhuolei Han, Jing Cui, Hao Luo, Yucen Li, Zhixin Xu, Jun Yang, Q. Bao, C. Jing, Jianwei Fu, Jiangong Cheng, Shaohua Liu
Bio-inspired hierarchical self-assembly provides elegant and powerful bottom-up strategies for the creation of complex materials. However, the current self-assembly approaches for natural bio-compounds often result in materials with limited diversity and complexity in architecture as well as microstructure. Here, we develop a novel coordination polymerization-driven hierarchical assembly of micelle strategy, using phytic acid-based natural compounds as an example, for the spatially controlled fabrication of metal coordination bio-polymers. The aliphatic surfactant pentadecafluorooctanoic acid and block co-polymer of polystyrene-b-poly (ethylene oxide) are assembled into two kinds of the discrete amphiphilic micelles. They evolve into hollow vesicles surrounding with spherical micelles, driven by the strong interaction triggered by coordination polymerization of ferric phytate precursors, which in turn facilitate the growth of precursors in a confined space. Consequently, the synchronous control on morphology and mesoscale structure for bio-compounds was successfully achieved for the first time. The resultant ferric phytate bio-polymer nanospheres feature hollow architecture, ordered meso-channels of ~12 nm, high surface area of 401 m2g-1, and large pore volume of 0.53 cm3g-1. As an advanced anode material, this bio-derivative metal coordination polymer delivers a remarkable reversible capacity of 540 mAh g-1 at 50 mA g-1, good rate capability and cycling stability for the use in sodium ion batteries. This study holds great potential of the design of new complex bio-materials with supramolecular chemistry.
生物启发的分层自组装为复杂材料的创建提供了优雅而强大的自下而上策略。然而，目前天然生物化合物的自组装方法往往导致材料在结构和微观结构上的多样性和复杂性有限。本文以植酸为基础的天然化合物为例，开发了一种新型的配位聚合驱动的胶束分层组装策略，用于空间控制金属配位生物聚合物的制造。将脂肪族表面活性剂五氟辛酸和聚苯乙烯-聚环氧乙烷嵌段共聚物组装成两种离散的两亲性胶束。在植酸铁前体配位聚合引发的强相互作用的驱动下，它们演变成被球形胶束包围的中空囊泡，这反过来又促进了前体在有限空间中的生长。因此，首次成功地实现了对生物化合物形态和中尺度结构的同步控制。所制得的植酸铁生物聚合物纳米球具有中空结构、~12 nm有序介孔、401 m2g-1的高表面积和0.53 cm3g-1的大孔体积等特点。作为一种先进的阳极材料，这种生物衍生物金属配位聚合物在50ma g-1时具有540 mAh g-1的可逆容量，具有良好的倍率能力和循环稳定性，适用于钠离子电池。该研究在设计具有超分子化学的新型复杂生物材料方面具有很大的潜力。
{"title":"Polymerization-Driven Hierarchical Co-Assembly of Micelles for Access to Mesoporous Hollow Metal Coordination Bio-Polymers","authors":"Yan Ai, Yuxiou You, Facai Wei, Xiaolin Jiang, Zhuolei Han, Jing Cui, Hao Luo, Yucen Li, Zhixin Xu, Jun Yang, Q. Bao, C. Jing, Jianwei Fu, Jiangong Cheng, Shaohua Liu","doi":"10.2139/ssrn.3448140","DOIUrl":"https://doi.org/10.2139/ssrn.3448140","url":null,"abstract":"Bio-inspired hierarchical self-assembly provides elegant and powerful bottom-up strategies for the creation of complex materials. However, the current self-assembly approaches for natural bio-compounds often result in materials with limited diversity and complexity in architecture as well as microstructure. Here, we develop a novel coordination polymerization-driven hierarchical assembly of micelle strategy, using phytic acid-based natural compounds as an example, for the spatially controlled fabrication of metal coordination bio-polymers. The aliphatic surfactant pentadecafluorooctanoic acid and block co-polymer of polystyrene-<i>b</i>-poly (ethylene oxide) are assembled into two kinds of the discrete amphiphilic micelles. They evolve into hollow vesicles surrounding with spherical micelles, driven by the strong interaction triggered by coordination polymerization of ferric phytate precursors, which in turn facilitate the growth of precursors in a confined space. Consequently, the synchronous control on morphology and mesoscale structure for bio-compounds was successfully achieved for the first time. The resultant ferric phytate bio-polymer nanospheres feature hollow architecture, ordered meso-channels of ~12 nm, high surface area of 401 m<sup>2</sup>g<sup>-1</sup>, and large pore volume of 0.53 cm<sup>3</sup>g<sup>-1</sup>. As an advanced anode material, this bio-derivative metal coordination polymer delivers a remarkable reversible capacity of 540 mAh g<sup>-1</sup> at 50 mA g<sup>-1</sup>, good rate capability and cycling stability for the use in sodium ion batteries. This study holds great potential of the design of new complex bio-materials with supramolecular chemistry.","PeriodicalId":8795,"journal":{"name":"Biochemistry eJournal","volume":"45 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84644608","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Michio Suzuki, K. Kubota, R. Nishimura, L. Negishi, K. Komatsu, H. Kagi, Katya Rehav, S. Cohen, I. Pinkas
The bivalve hinge ligament holds the two shells together. The ligament functions as a spring to open the shells after they were closed by the adductor muscle. The ligament is a mineralized tissue that bears no resemblance to any other known tissue. About half the ligament is composed of a protein-rich matrix, and half of long and extremely thin segmented aragonite crystals. Here we study the hinge ligament of the pearl oyster Pinctada fucata. FIB SEM shows that the 3D organization is remarkably ordered. The full sequence of the major protein component contains a continuous segment of 30 repeats of MMMLPD. There is no known homologous protein. Knockdown of this protein prevents crystal formation, demonstrating that the integrity of the matrix is necessary for crystals to form. X-ray diffraction shows that the aragonite crystals are more aligned in the compressed ligament, indicating that the crystals may be actively contributing to the elastic properties. The fusion interphase that joins the ligament to the shell nacre is composed of a prismatic mineralized tissue with a thin organic-rich layer at its center. Nanoindentation of the dry interphase shows that the elastic modulus of the nacre adjacent to the interphase gradually decreases until it approximates that of the interphase. The interphase modulus slightly increases until it matches the ligament. All these observations demonstrate that the ligament shell complex is a remarkable biological tissue that has evolved unique properties that enable bivalves to open their shell effectively innumerable times during the lifetime of the animal.
{"title":"A Unique Methionine-Rich Protein - Aragonite Crystal Complex: Structure and Mechanical Functions of the Pinctada Fucata Bivalve Hinge Ligament","authors":"Michio Suzuki, K. Kubota, R. Nishimura, L. Negishi, K. Komatsu, H. Kagi, Katya Rehav, S. Cohen, I. Pinkas","doi":"10.2139/ssrn.3424545","DOIUrl":"https://doi.org/10.2139/ssrn.3424545","url":null,"abstract":"The bivalve hinge ligament holds the two shells together. The ligament functions as a spring to open the shells after they were closed by the adductor muscle. The ligament is a mineralized tissue that bears no resemblance to any other known tissue. About half the ligament is composed of a protein-rich matrix, and half of long and extremely thin segmented aragonite crystals. Here we study the hinge ligament of the pearl oyster Pinctada fucata. FIB SEM shows that the 3D organization is remarkably ordered. The full sequence of the major protein component contains a continuous segment of 30 repeats of MMMLPD. There is no known homologous protein. Knockdown of this protein prevents crystal formation, demonstrating that the integrity of the matrix is necessary for crystals to form. X-ray diffraction shows that the aragonite crystals are more aligned in the compressed ligament, indicating that the crystals may be actively contributing to the elastic properties. The fusion interphase that joins the ligament to the shell nacre is composed of a prismatic mineralized tissue with a thin organic-rich layer at its center. Nanoindentation of the dry interphase shows that the elastic modulus of the nacre adjacent to the interphase gradually decreases until it approximates that of the interphase. The interphase modulus slightly increases until it matches the ligament. All these observations demonstrate that the ligament shell complex is a remarkable biological tissue that has evolved unique properties that enable bivalves to open their shell effectively innumerable times during the lifetime of the animal.","PeriodicalId":8795,"journal":{"name":"Biochemistry eJournal","volume":"14 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77608993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study evaluated the feasibility of reintroducing mechanical weed control as an alter-native for herbicide- resistance weed infestations. The production practice tested included row cultivation with a separate banded spray application using high- accuracy automated guidance systems. A range of ground speeds were tested for the row cultivation opera-tion, each with a different per acre cost and timeliness penalty. A typical eastern Corn Belt farm with a rotation of corn and soybean served as the base for the linear pro-gramming model. It was found that if the farmer was willing to reintroduce tillage, row cultivation conducted at higher operating speeds in conjunction with separate banded application could be justified under a range of relatively inexpensive herbicide costs as low as $7 per acre. When effective herbicides were relatively expensive at $30 per acre, the optimal decision would be to use row cultivation and reduce herbicides via banding. At faster ground speeds, the majority of hours devoted to row cultivation shifted to ear-lier time periods so that yield penalties were avoided.
{"title":"Impact of Automated Guidance for Mechanical Control of Herbicide Resistant Weeds in Corn","authors":"T. Griffin, J. Lowenberg-Deboer","doi":"10.2139/ssrn.2992647","DOIUrl":"https://doi.org/10.2139/ssrn.2992647","url":null,"abstract":"This study evaluated the feasibility of reintroducing mechanical weed control as an alter-native for herbicide- resistance weed infestations. The production practice tested included row cultivation with a separate banded spray application using high- accuracy automated guidance systems. A range of ground speeds were tested for the row cultivation opera-tion, each with a different per acre cost and timeliness penalty. A typical eastern Corn Belt farm with a rotation of corn and soybean served as the base for the linear pro-gramming model. It was found that if the farmer was willing to reintroduce tillage, row cultivation conducted at higher operating speeds in conjunction with separate banded application could be justified under a range of relatively inexpensive herbicide costs as low as $7 per acre. When effective herbicides were relatively expensive at $30 per acre, the optimal decision would be to use row cultivation and reduce herbicides via banding. At faster ground speeds, the majority of hours devoted to row cultivation shifted to ear-lier time periods so that yield penalties were avoided.","PeriodicalId":8795,"journal":{"name":"Biochemistry eJournal","volume":"59 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82443150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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