Menu
  • Publish High Quality Research/Review Articles for just USD $99*+Taxes( *T&C Apply)

    Offer Ends On

Review Article

Sorghum as a Potential Source of Sustainable Bioenergy Crop

Hina Saleem*, Hafeez Ahmad Sadaqat, Humera Razzaq and Javeria Ramazan

Corresponding Author: Hina Saleem, Department of Plant Breeding and Genetics, University of Agriculture, Faisalabad 38040, Pakistan

Received: May 25, 2022 ;    Revised: July 11, 2022 ;    Accepted: July 14, 2022   

Citation: Saleem H, Sadaqat HA, Razzaq H & Ramazan J. (2022) Sorghum as a Potential Source of Sustainable Bioenergy Crop. J Agric For Meterol Stud, 1(1): 1-6.

Copyrights: ©2022 Saleem H, Sadaqat HA, Razzaq H & Ramazan J. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Share Your Publication :

Views & Citations

307


Global Views

  • Abstract
  • Full Text
  • Images
  • Tables
  • References
  • PDF
  • Supplementary Files

Abstract

Sorghum is a promising crop for biofuel creation. It is a C4 crop with low input requirements. Abundance of sugars in its stalks. Considering this, many studies have been done to create genetic and genomic resources for sorghum. In this paper, we examine different characteristics of sweet sorghum that make it an optimal possibility for biofuel feedstock, and give an outline of variety, benefits accessible for designing sorghum crop for improvement. At long last, the advancement made up until this point, in identification of qualities/quantitative attribute loci (QTLs) significant for agronomic characteristics. Here natural attributes like abiotic strain tolerance, various genetic base, viable seed industry, and sound breeding system make sorghum an ideal candidate for setting up an efficient and low-cost biofuel enterprise. Scientists are exploring methods to exploit forage, and biomass sorghums as climate-smart power crops. In this context, traditional breeding has played a vital function in developing excessive-yielding sorghum cultivars. For biomass sorghum, stem compositional analysis allows display screen low lignin and high polysaccharide types as feedstocks for biofuels. Current tools of phenomics, genomics, proteomics, and genome enhancing are key gamers of designing green bioenergy sorghum.

Keywords: Sorghum, Feedstock, Cultivar, Phenomics, Proteomics

INTRODUCTION

Climate change is a challenging factor that has affected the mankind since past few decades and therefore the constant supply of sustainable energy is the dire need of time. Biomass is potentially the largest contributor for fulfilling the energy demand in a sustainable manner. It has great significance for enhancing the production of electricity, heat and fuels for the transport. If biomass is carefully managed it can supply with:

  • Significant reduction in greenhouse gasses emission.
  • Provides developmental benefits in terms of energy.
  • Reducing the issues of waste disposal.
  • Providing scope for using residues and waste.

Biomass, today supplies some 50 EJ1 globally, which represents 10% of global annual primary energy consumption. This is mostly traditional biomass used for cooking and heating (Figure 1).

 

Every year from a number of crops a large volume of lignocellulosic biomass is produced. This has increased the crop use efficiency. Various crops have now entered in the bioenergy and biomass production cycle making many countries self-sufficient in terms of energy. Crops at present provides with as the best source of alternative form of energy.

The utilization of natural waste and farming/forestry deposits, and of lignocellulosic crops that could be developed on a more extensive range of land types, may alleviate land and water interest and lessen competition with food. Energy crops acts as a filter system provides the supplemental yields, controls pollution as they eliminate pesticides and abundance compost from surface water before it dirties groundwater or streams/waterways. They can secure a stream's bank and water from disintegration, siltation, and factories spill.

They likewise require less composts, herbicides and insecticides than traditional crops, this decrease in herbicide and pesticide use. One more ecological advantage from the utilization of energy crops is a diminishing in emanations. In contrast to non-renewable energy sources, plants developed for energy crops absorbs carbon dioxide (CO2) delivered during their combustion/use.

Designing climate-resilliant energy crop with optimized composition to suit the, consumers the industry and the growers is the backbone of cost-competitive biofuel industry. C4 grasses provide a perfect fit to this definition owing to higher, productivity, photosynthetic rate, and broader genetic base of germplasm. Sorghum is a short duration crop of about 3-4 months and produces higher biomass yield with less inputs. These characteristics make sorghum a popular biofuel feedstock [1]. Sorghum has different end-use types including biomass, forage, sweet, and grain sorghums. Energy sorghum including biomass and sweet type varieties is the most efficient and climate-smart feedstock being able to grow with less inputs on marginal lands under harsh climatic conditions and having ability to utilize more sunlight [2-4]. The growth stages of sesame are illustrated in Figure 2 & Table 1.

SORGHUM BIOMASS POTENTIAL

Sorghum biomass is impacted by genetics and ecological elements [5]. The distinguishing proof of variety in phenotypic, hereditary, underlying, and physiological characters of energy sorghum is fundamental to its improvement. Sorghum biomass improvement model depends on coordinating a few genomic-helped strategies with phenomics approaches. Normal field-based choice of high biomass sorghum relies on describing biomass-related morphological characteristics like days to flowering (days subsequent to planting), plant height, new biomass yield, dry matter, and dry matter yield, plant growth habit, stem width, leaf number, leaf area, leaf length, leaf point and leaf area index, and so on [6]. A few investigations report on morphological variety evaluation of sorghum for biomass characteristics in the field climate [7,8].

Precise and far reaching phenotypic information are the pattern to clarify hereditary components fundamental complex quantitative biomass qualities. Since biomass-related qualities are estimated through dangerous inspecting, recording morphological information during the whole developing time of energy sorghum is conceivable just a single time. Manual, nondestructive examining for these characteristics over complete advancement of sorghum is unthinkable. When contrasted with moderately less expensive innovations of genomic choice, affiliation planning and GWAS, dependable phenotyping is difficult and costly. Around 20 years back while genotyping strategies were quick progressing; improving phenotyping approaches was totally disregarded. As of late, there has been a developing interest in creating successful sorghum phenotyping techniques. The work began with advancing high-throughput phenotyping frameworks for model plants under controlled conditions. Later on, field-based phenotyping stages were contrived for short height crops [9]. Over the most recent 5 years, various methodologies have been excogitated with promising abilities of recording sorghum phenology in field conditions. A portion of these 

incorporate different UAS stages [10,11], field-based automated phenotyping framework [12], automated airborne framework [13], ultrasonic sensors [14], the light identification and running (LiDAR) [15], the hour of flight cameras [16], tomography imaging [17], Kinect v2 camera [18], RGB and NIR imaging [19], and Phenobot 1.0 [20]. The cutting edge phenomics devices produce huge measure of information that is being interpreted by means of AI factual methodologies into quality depictions, pertinent to sorghum growers [21].

Production of biomass from stem of sorghum

The composition of biomass extracted from grain, forage and sweet sorghums has been very much characterized [22]. Exploitation of sorghum as biofuel was started in 1980s, which prompted the improvement of photoperiod-sensitive energy sorghum hybrids [23]. These are high biomass yielders [24]. Being newly introduced, the stem structure information on energy sorghum is still limited and restricted. Up till now, a greater part of research on sorghum biomass feedstock has focused on more on improvement in developing better yield than the quality parts. In this way, there is a need to precisely lead the biochemical analysis, since stem structure is the fundamental component affecting biofuel yield.

Plant cell walls are the fundamental constituents of biomass that give strength and limited plasticity to cell. The cell wall fills in as an intense physical barrier, ensuring inside of the cell and its contents against biotic and abiotic stresses. It is a complex structure made out of polysaccharides and proteins, which are significant benefactors of biofuel quality and energy conversion process. The polysaccharides are cellulose (a polymer of glucose), pectic mixtures (polymers of galacturonic corrosive), and hemicellulose (a polymer of an assortment of sugars including xylose, arabinose, and mannose). Cellulose is the biggest source of glucose for biofuels. Glucuronoarabinoxylan (GAX) hemicellulose complex is connected to lignin. Since lignin part of plant cell wall gives structure, it can't be changed over to carbohydrates and thus is recalcitrant to conversion process. Moreover, ash content likewise reduces biomass to biofuel change response. Certain constituents of cell wall are water solvent like sugars, proteins, amino acids, mixed linkage glucans, and phenolic glycosides, while chlorophyll, lipids, and waxes are water-insoluble fixings that need ethanol extraction.

Various experiments have reported different methodologies for compositional analysis of energy sorghum leaves and stem. In some sorghum genotypes, extent of cellulose can fluctuate somewhere in the range of 27 and 52%, while the content of hemicellulose content is 17-23% and lignin content is 6.2-8.1% [25,26]. Alongside the biomass yield, low lignin, high cellulose, and hemicellulose substance are likewise the helpful determination credits for energy sorghum genotypes [27]. Such sorghums display wide varieties in biomass structure [28]. Presently, near infrared spectroscopic (NIR) analysis is regularly utilized for high-throughput calculation of biomass structure [29].

Cellulosic bioethanol creation requires three fundamental stages: pretreatment, hydrolysis and maturation [30] (Figure 3). Pretreatment is performed to fractionate lignocellulose into various parts through physical (bubbling, steaming, and ultrasonication), compound (corrosive, antacid, salts, and so on), physiochemical (ammonium fiber blast or AFEX), and natural techniques (microbes and parasites). It expands porosity and surface space of the substrate. During hydrolysis, nonstructural carbs are corrupted in to sugars. Chemical based hydrolysis is liked over corrosive hydrolysis being a gentle and savvy measure. 

Sweet sorghum as a multipurpose crop. The various uses of sweet sorghum juice, grains, and other byproducts have been illustrated below (Figure 4).

GENES AND QTLs GOVERNING BIOFUEL-RELATED TRAITS

Associating hereditary units like QTLs to the entirety genome can give data about putative applicants administering explicit qualities. Mace and colleagues [31] incorporated the entire genome grouping data with sorghum QTLs by projecting 771 QTLsonto sorghum agreement map, consequently giving a valuable asset for planning productive procedures for marker-helped rearing. Afterward, a chart book of QTLs for biofuel-related attributes in sorghum regarding their chromosomal areas was assembled. It incorporates 858 biofuel-related QTLs that can be straightforwardly utilized in sweet sorghum reproducing to accomplish better returns, more biomass, higher stem solvent sugars on the minimal lands, etc. [32]. A relative genomic data set named TeComparative Saccharinae Genome Resource (CSGR)- QTL has been intended for cross-usage of the data among individuals from Saccharinae clade and different clades of grasses [33]. Te data set contains QTL data for Sorghum, Saccharum, Miscanthus, also, rice. Te term "Biofuel Syndrome" is utilized to allude to the gathering of characteristics in sweet sorghum (flowering time, plant design, and biomass change efficiency) that are significant for biofuel creation [34]. Underneath, we sum up the investigations that have been completed to comprehend the hereditary premise of these characteristics in sweet sorghum.

CONCLUSION

Sorghum, with its variety of versatile components and low info prerequisites, is one of the main crop for biofuel feedstock. It can possibly address two significant issues. Initially, it can assume a critical part in addressing the developing requirement for sustainable power to uproot petroleum derivative based energy assets. Besides, rather than rivaling food crops for arable land, it will rather help in protection of negligible grounds by changing them over to horticultural land. In any case, Sorghum shows tremendous hereditary variety and assets towards area explicit climatic conditions or changing climatic conditions, and measure of fermentable sugars and grain yields fluctuate impressively in various sweet sorghum cultivars. Subsequently, screening and choice of suitable assortments for every area is basic for ideal outcomes.

DATA AVAILABILITY

The data that support the findings of this study are available on request from the corresponding author.

REFERENCES

  1. Ratnavathi C, Suresh K, Kumar BV, Pallavi M, Komala V, et al. (2010) Study on genotypic variation for ethanol production from sweet sorghum juice. Biomass Bioenergy 34: 947-952.
  2. Xie GH (2012) Progress and direction of non-food biomass feedstock supply research and development in China. J China Agric Univ 17: 1-19.
  3. Olson SN, Ritter K, Rooney W, Kemanian A, McCarl BA, et al. (2012) High biomass yield energy sorghum: Developing a genetic model for C4 grass bioenergy crops. Biofuel Bioprod Biorefin 6: 640-655.
  4. Paterson A, Bowers JE, Bruggmann R, Dubchak I, Grimwood J, et al. (2009) The Sorghum bicolor genome and the diversification of grasses. Nature 457: 551-556.
  5. Boyles RE, Brenton ZW, Kresovich S (2019) Genetic and genomic resources of sorghum to connect genotype with phenotype in contrasting environments. Plant J 97(1): 19-39.
  6. da Silva MJ, Carneiro PCS, Carneiro JES, Damasceno CMB, Parrella NNLD, et al. (2018) Evaluation of the potential of lines and hybrids of biomass sorghum. Ind Crops Prod 125: 379-385.
  7. Betts NS, Fox GP, Kelly AM, Cruickshank AW, Lahnstein J, et al. (2015) Non-cellulosic cell wall polysaccharides are subject to genotype ×environment effects in sorghum (Sorghum bicolor) grain. J Cereal Sci 63: 64-71.
  8. Arshad SF, Sadia B, Awan FS, Jaskani MJ (2017) Estimation of genetic divergence among sorghum germplasm of Pakistan through multivariate tools. Int J Agric Biol 19: 1099-1106.
  9. Dossou-Aminon I, Loko YL, Adjatin A, Dansi A, Elangovan M, et al. (2014) Diversity, genetic erosion and farmer’s preference of sorghum varieties [Sorghum bicolor (L.) Moench] growing in North-Eastern Benin. Int J Curr Microbiol Appl Sci 3: 531-552.
  10. Safdar H (2018) Application of microsatellites in genetic diversity analysis of USDA sorghum germplasm [MPhil dissertation]. Pakistan: University of Agriculture, Faisalabad.
  11. Shoemaker CE, Bransby DI (2010) The role of sorghum as a bioenergy feedstock. In: Braun R, Karlen D, Johnson D, editors. Sustainable alternative fuel feedstock opportunities, challenges and roadmaps for six US regions. Atlanta: Soil and Water Conservation Society. pp: 149-159.
  12. Codesido V, Vacas R, Macarulla B, Gracia MP, Igartua E (2013) Agronomic and digital phenotyping evaluation of sweet sorghum public varieties and F1 hybrids with potential for ethanol production in Spain. Maydica 58: 42-53.
  13. Whitfeld MB, Chinn MS, Veal MW (2012) Processing of materials derived from sweet sorghum for biobased products. Ind Crops Prod 37(1): 362-375.
  14. Qazi HA, Paranjpe S, Bhargava S (2012) Stem sugar accumulation in sweet sorghum-activity and expression of sucrose metabolizing enzymes and sucrose transporters. J Plant Physiol 169(6): 605-613.
  15. Almodares A, Sepahi A (1996) Comparison among sweet sorghum cultivars, lines and hybrids for sugar production. Ann Plant Physiol 10: 50-55.
  16. Vinutha KS, Rayaprolu L, Yadagiri K, Umakanth AV, Patil JV, et al. (2014) Sweet sorghum research and development in India: Status and prospects. Sugar Tech 16(2): 133-143.
  17. Kawahigashi H, Kasuga S, Okuizumi H, Hiradate S, Yonemaru JI (2013) Evaluation of brix and sugar content in stem juice from sorghum varieties. Grassl Sci 59(1): 11-19.
  18. Regassa TH, Wortmann CS (2014) Sweet sorghum as a bioenergy crop: Literature review. Biomass Bioenergy 64: 348-355.
  19. Almodares A, Hadi MR, Kholdebarin B, Samedani B, Kharazian ZA (2014) The response of sweet sorghum cultivars to salt stress and accumulation of Na+, Cl− and K+ ions in relation to salinity. J Environ Biol 35(4): 733-739.
  20. Sayyad-Amin P, Jahansooz MR, Borzouei A, Ajili F (2016) Changes in photosynthetic pigments and chlorophyll-a fluorescence attributes of sweet-forage and grain sorghum cultivars under salt stress. J Biol Phys 42(4): 601-620.
  21. Wang WF, Zong YZ, Zhang SQ (2014) Water and nitrogen use efficiencies of sweet sorghum seedlings are improved under water stress. Int J Agric Biol 16(2): 285-292.
  22. Edwards EJ, Osborne CP, Stromberg CA, Smith SA, Bond WJ, et al. (2010) The origins of C4 grasslands: Integrating evolutionary and ecosystem science. Science 328(5978): 587-391.
  23. Billings M (2015) Biomass sorghum and sweet sorghum data gathering report In: W&A Crop Insurance. USDA-RMA, CTOR: Jaime Padget, Missouri Watts and Associates, Inc.
  24. Reddy BVS, Kumar AA, Ramesh S (2006) Sweet sorghum: A water saving bioenergy crop. In: ICRISAT, Patancheru, Andhra Pradesh, India. pp: 1-12. Accessed on: April 13, 2017. Available online at: http://www.iwmi.cgiar.org/EWMA/fles/papers/PaperforBioenergyandwater-BelumReddy.pdf
  25. Rutto LK, Xu Y, Brandt M, Ren S, Kering MK (2013) Juice, ethanol and grain yield potential of five sweet sorghum (Sorghum bicolor [L.] Moench) cultivars. J Sustain Bioenergy Syst 3(2): 113-118.
  26. Reddy BVS, Ramesh S, Reddy PS, Kumar AA, Sharma KK, et al. (2006) Sweet sorghum food, feed, fodder and fuel crop. In: International Crops Research Institute for the Semi-Arid Tropics, http:// oar.icrisat.org/2598/, Patancheru, India: ICRISAT; pp: 1-24.
  27. Rao PS, Kumar CG, Reddy BVS (2012) Sweet sorghum: from theory to practice. In: Rao PS, Kumar CG, editors. Characterization of improved sweet sorghum cultivars. Berlin: Springer; pp: 1-15.
  28. Sweet Sorghum Bagasse: excellent nonwood source for handmade papermaking. Agribusiness. Available online at: http://www.pinoybisnes.com/agribusiness/sweet-sorghum-bagasse-excellent-nonwood-source-forhandmade-papermaking/
  29. Disasa T, Feyissa T, Admassu B (2016) Characterization of Ethiopian sweet sorghum accessions for brix, morphological and grain yield traits. Sugar Tech 19: 1-11.
  30. Vermerris W, Erickson J, Wright D, Newman Y, Rainbolt C (2008) Production of biofuel crops in Florida: Sweet sorghum. In: Publication of Agronomy Department, No. SS-AGR-293. Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida, Florida, USA.
  31. Mace ES, Jordan DR (2011) Integrating sorghum whole genome sequence information with a compendium of sorghum QTL studies reveals uneven distribution of QTL and of gene-rich regions with significant implications for crop improvement. Theor Appl Genet 123(1): 1691.
  32. Anami SE, Zhang LM, Xia Y, Zhang YM, Liu ZQ, et al. (2015) Sweet sorghum ideotypes: Genetic improvement of the biofuel syndrome. Food Energy Secur 4(3): 159-177.
  33. Zhang D, Guo H, Kim C, Lee TH, Li J, et al. (2013) CSGRqtl, a comparative quantitative trait locus database for saccharine grasses. Plant Physiol 161(2): 594-599.
  34. Anami SE, Zhang LM, Xia Y, Zhang YM, Liu ZQ, et al. (2015) Sweet sorghum ideotypes: Genetic improvement of stress tolerance. Food Energy Secur 4(1): 3-24.

    No Files Found