Genetic Engineering in Sugarcane Improvement: Adaptability, Achievements, Limitations and Prospects
XU Fu, WANG Zhou-Tao, LU Gui-Long, QUE You-Xiong*
Key Laboratory of Sugarcane Biology and Genetic Breeding, Ministry of Agriculture, Fujian Agriculture and Forestry University / Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China
Abstract：Sugarcane (Saccharum spp. complex) is a major species of the gramineous family and an economically important crop, which plays an important role in the development of world agricultural economy and the guarantee of sugar supply. One hand, sugarcane is known as a pioneer crop, as it has good resistance or tolerance to abiotic adversity. However, its production and productivity are constrained by various abiotic and biotic stresses, resulting in a serious loss in cane yield and sugar content. On the other hand, sugarcane flowering and fruiting requires strict light and temperature conditions, and hybridization is generally adopted by selecting suitable sites to induce the parents to flower in all countries, together with a photoperiod chamber. Normally, many commercial cultivated varieties generally do not blossom in the process of cultivation, and there is no seed even though they flower in a certain location in some years. In addition, sugarcane is an industrial raw material crop, and its product sucrose is carbohydrate and does not contain protein. Therefore, the safety risk level of transgenic sugarcane is low, second only to non-food crops, such as cotton. Furthermore, sugarcane is an asexually propagated crop, and once excellent transgenic individual plants are obtained, its population can be rapidly expanded by tissue culture. Genetic engineering has become an important means for sugarcane to make up for the defects of traits derived from traditional crossbreeding and to accelerate the process of genetic improvement. Regarding why sugarcane is a suitable species for transgenic improvement, this paper highlighted the achievements of improvement of insect pest resistance and disease resistance, briefly reviewed the improvement of other traits and the work of sugarcane as a bioreactor. Then, we focus on the factors affecting the efficiency of genetic transformation and the expression level of exogenous target genes in sugarcane. Additionally, the progress of gene-editing in sugarcane was reviewed. Finally, the future of transgenic sugarcane was prospected. The present review aims to promote the application of genetic engineering in sugarcane improvement.
[1] 冯翠莲, 张树珍. 2010. CryIA(c)和gna 融合基因植物表达载体的构建[J]. 热带作物学报, 31(2): 224-228. (Feng C L, Zhang S .2010. Construction of expression vector harboring CryIA(c) and gna fusion gene[J]. Chinese Journal of Tropical Crops, 31(2): 224-228.) [2] 冯翠莲, 万玥, 赵婷婷, 王俊刚, 冯小艳, 张树珍. 2020. 抗虫转基因甘蔗对土壤酶活性的影响[J]. 热带生物学报, 11(1): 1-6. (Feng C L, Wan Y, Zhao T T, Wang J G, Feng X YM, Zhang S Z.2020. Effect of insect-resistant transgenic sugarcane on soil enzyme activities in the rhizosphere[J]. Journal of Tropical Biology, 2020. 11(1): 1-6.) [3] 冯翠莲, 张树珍. 2020. 抗虫转基因甘蔗的培育及其抗性丧失的防控策略. 生物技术通报, 36(7): 209-219. (Feng C L, Zhang S Z.2020. Breeding of transgenic insect-resistant sugarcane and strategies for preventing the its resistance to insects from loss[J]. Biotechnology Bulletin, 36(7): 209-219. [4] 高世武, 阙友雄, 郭晋隆, 许莉萍, 陈如凯. 2010. 甘露糖筛选系统的建立及在甘蔗转基因中的应用[J].热带作物学报, 31(5): 789-796. (Gao S W, Que Y X, Guo JL, Xu L P, Chen R K.2010. Establishment of a novel selection system by mannose and its application in sugarcane transformation[J]. Chinese Journal of Tropical Crops, 31(5): 789-796.) [5] 高世武. 2008. Cry基因遗传转化甘蔗的研究[D]. 硕士学位论文, 福建农林大学,导师: 陈如凯, 许莉萍, pp. 36-70. (Gao S W.2008. Study on genetic transformation of sugarcane with Cry gene [D]. Thesis for M.S., Fujian Agriculture and Forestry University,, Suppervisor: Chen R K, Xu L P, pp.36-70.) [6] 顾丽红, 张树珍, 杨本鹏, 等. 2008. 几丁质酶和β-1,3-葡聚糖酶基因导入甘蔗[J]. 分子植物育种, 6(2): 277-280. (Gu L H, Zhang S Z, Yang B P, et al.2008. Introduction of chitin and β-1,3-glucan into sugarcane[J]. Molecular Plant Breeding, 6(2): 277-280. [7] 李文凤, 单红丽, 王晓燕, 等. 2017. 滇蔗茅杂交F1双抗SCSMV和SrMV 鉴定与评价. 植物遗传资源学报, 18( 5) : 886-890. (Li W F, Shan H L, Wang X Y, et al.2017. Identification and evaluation of elite sugarcane innovation germplasm resistant to SCSMV and SrMV[J]. Journal of Plant Genetic Resources, 18( 5) : 886-890.) [8] 林庆良, 许莉萍, 高世武, 等. 2010. 甘蔗胚性愈伤组织发生与发育的组织细胞学观察[J]. 热带作物学报, 31(8): 1-6. (Lin Q L, Xu L P, Gao S W, et al.2010. Cytohistological examination of embryogenesis in sugarcane[J]. Chinese Journal of Tropical Crops, 31(8): 1-6.) [9] 阙友雄, 林庆良, 许莉萍, 等. 2012. 一种简便的农杆菌介导甘蔗转基因方法[P]. 中国, 102559748B. (Que Y X, Lin Q L, Xu L P, et al.2012. A simple Agrobacterium mediated sugarcane transgenic method [P]. China, 102559748B.) [10] 世农. 2018. 巴西糖厂开始种植全球第一批转基因甘蔗[J]. 中国食品学报, 18(3): 66. (Shi N.2018. Brazilian sugar mills start planting the world's first batch of genetically modified sugarcane[J]. Journal of Chinese Institute of Food Science and Technology, 18(3): 66.) [11] 王天云, 柴玉荣, 袁保梅, 等. 2004. 核基质结合区对转基因表达的影响及其作用机制[J]. 细胞生物学杂志, 26: 587-590. (Wang T Y, Chai Y R, Yuan B M, et al.2004. Effects and the mechanism of nuclear matrix attachment regions on the transgenic expression[J]. Chinese Journal of Cell Biology, 26: 587-590.) [12] 王文治, 胡天娇, 杨本鹏, 等. 2020. 转 Cry2A 基因抗虫甘蔗植株的培育[J]. 分子植物育种, 18(9): 2893-2898. (Wang W Z, Hu T J, Yang B P, et al.2020. Nature of pest resistant sugarcane by genetic transformation of Cry2A gene[J]. Molecular Plant Breeding, 18(9): 2893-2898.) [13] 王露蓉, 黄婵, 顾彩彩, 等. 2018. 转SoSUT5基因甘蔗的生长特性[J]. 南方农业学报, 49(5): 857-862. (Wang R L Huang C, Gu C C, Song Q Q, Yang L T, Xing Y X, Nong Y Y, Li Y R.2018. Growth characteristics of SoSUT5 transgenic sugarcane[J]. Journal of Southern Agriculture, 49(5): 857-862.) [14] 许莉萍, 潘大仁, 陈如凯. 2001. 基因工程甘蔗: 潜能、现状和前景[J]. 生物工程学报, 17(4): 371-374. (Xu L P, Pan D R, Chen R K.2001. Genetic engineering sugarcane: Potential,current status and prospects[J]. Chinese Journal of Biotechnology, 17(4): 371-374.) [15] 吴杨. 2009. 斑茅DREB2B基因遗传转化甘蔗的抗旱性研究 [D].博士学位论文, 福建农林大学, 导师: 张木清, pp. 63-103. (Wu Y.2009. The study on drought resistance of genetic transformation of Erianthus arundinaceus's DREB2B gene into sugarcane [D]. Thesis for Ph.D., Fujian Agriculture and Forestry University, Suppervisor: Zhang M Q, pp. 63-103.) [16] 杨晓杰, 刘传亮, 张朝军, 等. 2011. 不同转化方法获得的转基因棉花外源基因拷贝数分析[J]. 农业生物技术学报, 19(2): 221-229. (Yang X J, Liu C L, Zhang C J, et al.2001. Comparative analysis of exogenous gene copy numbers in transgenic cotton transformed by different methods[J]. Journal of Agricultural Biotechnology, 19(2): 221-229.) [17] 姚伟, 余爱丽, 徐景升, 等.2004. 转ScMV-CP基因甘蔗的分子生物学分析与鉴定[J]. 分子植物育种, 2004, 2: 13-18. (Yao W, Yu A L, Xu J S, 2004. Analysis and identification for transgenic sugarcane of ScMV-CP gene[J]. Molecular Plant Breeding, 26: 587-590.) [18] 于兰, 秦新民, 黄德青. 2007. 农杆菌介导的BT基因导入甘蔗的研究[J]. 广西农学报, 22(6): 1-4, 67. (Yu L, Qin X M, Huang D Q.2007. Studies on BT gene transformation sugarcane by Agrobacterium[J]. Journal of Guangxi Agriculture, 22(6): 1-4, 67.) [19] 张树珍, 王文治, 冯翠莲, 等. 2010. 一种高效快速的甘蔗转基因方法[P]. 中国, 101768604A. (Zhang S Z, Wang W Z, Feng C L, et al.2010. An efficient and rapid transgenic method for sugarcane [P]. China, 101768604A.) [20] 张雨良, 熊国如, 王健华, 等. 2011. 甘蔗黄叶病毒CP 蛋白基因ihpRNA 表达载体构建及烟草转化[J]. 植物研究, 31(5): 537-542. (Zhang Y L, Xiong G R, Wang J H, et al.2011. Construction of ihpRNA expression vector of sugarcane yellow leaf virus CP protein gene and genetic transformation in tabacco[J]. Bulletin of Botanical Research, 31(5): 537-542.) [21] Anwar M S, Ali H W, Ahmad T, et al.2004. Integrated management of sugarcane insects[J]. Pakistan Sugarcane Journal, 6: 28-31. [22] Arencibia A, Vázquez R I, Prieto D, et al.1997. Transgenic sugarcane plants resistant to stem borer attack[J]. Molecular Breeding, 3: 247-255. [23] Bower R, Birch R G.1992. Transgenic sugarcane plants via microprojectile bombardment[J]. Plant Journal, 2: 409-416. [24] Casu R E, Selivanova A, Perroux J M.2012. High-throughput assessment of transgene copy number in sugarcane using real-time quantitative PCR[J]. Plant Cell Reports, 31:167-177. [25] Cheavegatti-Gianotto A, Gentile A, Oldemburgo D A, et al.2018. Lack of detection of Bt sugarcane Cry1Ab and NptII DNA and proteins in sugarcane processing products including raw sugar[J]. Frontier Bioengineering Biotechnology, 6: 1-14. [26] Cheng X Y, Ravinder S, Harvey K, et al.1998. Agrobacterium-transformed rice plants expressing synthetic cryIA(b) and cryIA(c) genes are highly toxic to striped stem borer and yellow stem borer[J]. Proceedings National Academy Sciences of the USA, 95(6): 2767-277. [27] Chowdhury M K U, Vasil I K.1992. Stably transformed herbicide resistant callus of sugarcane via microprojectile bombardment of cell suspension and electroporation of protoplasts[J]. Plant Cell Reports, 11: 494-498. [28] Cristofoletti P T, Kemper E L, Capella A N, et al.2018. Development of transgenic sugarcane resistant to sugarcane borer[J]. Tropical Plant Biology, 11: 17-30. [29] Dal-Bianco M, Carneiro M S, Hotta C T, et al.2012. Sugarcane improvement: how far can we go?[J] Current Opinion Biotechnology, 23: 265-70. [30] Dong S J, Delucca P, Geijskes R J, et al.2014. Advances in Agrobacterium-mediated sugarcane transformation and stable transgene expression[J]. Sugar Tech, 16(4): 366-371. [31] D'Hont A, Grivet L, Feldmann P, et al.1996. Characterisation of the double genome structure of modern sugarcane cultivars (Saccharum spp.) by molecular cytogenetics[J]. Molecular Genome Genetics, 250: 404-413. [32] de Setta N, Monteiro-Vitorello C B, Metcalfe C J, et al.2014. Building the sugarcane genome for biotechnology and identifying evolutionary trends[J]. BMC Genomics, 15: 540. [33] Eid A, Mohan C, Sanchez S, Wang D, et al.2021. Multiallelic, targeted mutagenesis of magnesium chelatase with CRISPR/Cas9 provides a rapidly scorable phenotype in highly polyploid sugarcane[J]. Frontier in Genome Editing, 3: 654996. [34] Estruch J J, Carozzi N B, Desai N, et al.1997. Transgenic plants: An emerging approach to pest control[J]. Nature Biotechnology, 15: 137-141. [35] Frederic R, Olivier L G, Thierry C, el a1.1999. New advances in understanding the molecular biology of plant potyvirus interaction[J]. Molecular Plant Microbe Interaction, 12(5): 367-376. [36] Fu X, Due L T, Fontana S, et al.2000. Linear transgenic constructs lacking vector backbone sequences generate low-copy-number transgenic plants with simple integration patterns[J]. Transgenic Research, 9:11-19. [37] Gao S, Yang Y, Wang C, et al.2016. Transgenic sugarcane with a cry1Ac gene exhibited better phenotypic traits and enhanced resistance against sugarcane borer[J]. PLOS ONE, 11(4): e0153929. [38] Gao S W, Yang Y Y, Xu L P, et al.2018. Particle bombardment of the cry2A gene cassette induces stem borer resistance in sugarcane[J]. International Journal of Molecular Sciences, 19: 1692. [39] Garsmeur O, Droc G, Antonise Ret al.2018. A mosaic monoploid reference sequence for the highly complex genome of sugarcane[J]. Nature Communications, 9: 2638. [40] Gianotti A, Rios W M, Soares-Costa A, et al.2006. Recombinant expression, purification, and functional analysis of two novel cystatins from sugarcane (Saccharum officinarum)[J]. Protein Expression and Purification, 47: 483-489. [41] Guo J L, Gao S W, Lin Q L, et al.2015. Transgenic sugarcane resistant to Sorghum mosaic virus based on coat protein gene silencing by RNA interference[J]. BioMed Research International, Article ID 861907. [42] Gupta P K.2006. RNA interference-gene silencing by double-stranded RNA: The 2006 Nobel Prize for Physiology or Medicine[J]. Current Science, 91(11): 10. [43] Hall G Jr, Allen G C, Loer D S, et al.1991. Nuclear scaffolds and scaffold-attachment regions in higher plants[J]. Proceedings National Academy Sciences of the USA, 88:9320-9324. [44] Handley J A, Smith G R, Dale J L, et al.1996. Sequence diversity in the Nib coding region of eight sugarcane mosaic potyvirus isolates infecting sugarcane in Australia[J]. Archives of Virology, 141: 2289-2300 [45] Harrison M D, Geijskes J, Coleman H D, et al.2011. Accumulation of recombinant cellobiohydrolase and endoglucanase in the leaves of mature transgenic sugar cane[J]. Plant Biotechnology Journal, 9: 884-896. [46] Hong Y L, Hunt A G.1996. RNA polymerase activity catalyzed by a potyvirus-encoded RNA-dependent RNA polymerase[J]. Virology, 226: 146-15l. [47] Islam M S, Yang X P, Sood S, et al.2018. Molecular characterization of genetic basis of Sugarcane yellow leaf virus (SCYLV) resistance in Saccharum spp. hybrid[J]. Plant Breeding, 137: 598-604. [48] Jackson M A, Sternes P R, Mudge S R, et al.2014. Design rules for efficient transgene expression in plants[J]. Plant Biotechnology Journal, 12: 925-933. [49] Joyce P A, McQualter R B, Handley J A, et al. 1998. Transgenic sugarcane resistant to Sugarcane mosaic virus[C]. In: Proceedings of the 20th Conference of the Australian Society of Sugar Cane Technologists, Ballina, Australia. [50] Kannan B, Jung J H, Moxley G W, et al.2018. TALEN-mediated targeted mutagenesis of more than 100 COMT copies/alleles in highly polyploid sugarcane improves saccharification efficiency without compromising biomass yield[J]. Plant Biotechnology Journal, 16: 856-866. [51] Kennedy R D, Cheavegatti-Gianotto A, de Oliveira W S, et al.2018. A general safety assessment for purified food ingredients derived from biotechnology crops: Case study of Brazilian sugar and beverages produced from insect-protected sugarcane[J]. Frontiers in Bioengineering and Biotechnology, 6: 45. [52] Kumar S, Fladung M.2002. Transgene integration in aspen: Structure of integration site and mechanism of T-DNA integration[J]. Plant Journal, 31: 543-551. [53] Kusaba M.2004. RNA interference in crop plants[J]. Current Opinion in Biotechnology, 15:139-143. [54] Le Cunff L, Garsmeur O, Raboin L M, et al.2008. Diploid/polyploid syntenic shuttle mapping and haplotype-specific chromosome walking toward a rust resistance gene (Bru1) in highly polyploid sugarcane (2n approximately 12x approximately 115)[J]. Genetics, 180: 649-660. [55] Legaspi J C, Legaspi B C, Irvine J E, et al.1999. Stalk-borer damage on yield and quality of sugarcane in lower Riogrande valley of Texas[J]. Journal of Economic Entomology, 92: 228-244. [56] Li Q W, Fan L, Luo Q, et al.2014. Co-overexpression of AtCBL9, AtCIPK23, and AtAKT1 enhances K+ uptake of sugarcane under low K+ stress[J]. Plant Omics Journal, 7(3):188-194 [57] Li Y R, Song X P, Wu J M, et al.2016. Sugar industry and improved sugarcane farming technologies in china[J]. Sugar Tech, 18: 603-611. [58] Li Z J T, Subramamnian J, Gray D J.2004. Bi-directional duplex promoters with duplicated enhancers significantly increase transgene expression in grape and tobacco[J]. Transgenic Research, 13: 143-154. [59] Lowe B A, Prakash N S, Way M, et al.2009. Enhanced single copy integration events in corn via particle bombardment using low quantities of DNA[J]. Transgenic Research, 18: 831-840. [60] Mehmet T Oz, Altpeter A, Karan R, et al.2021. CRISPR/Cas9 mediated multi-allelic gene targeting in sugarcane confers herbicide tolerance[J]. Frontiers in Genome Editing, 2021: 673566. [61] Mesnage R, Clair E, Gress E, et al.2013. Cytotoxicity on human cells of cry1Ab and cry1Ac Bt insecticidal toxins alone or with a glyphosate-based herbicide[J]. Journal of Applied Toxicology, 33(7): 695-699. [62] Milligan S B, Balzarini M, White W H.2003. Broad-sense heritabilities, genetic correlations, and selection indices for sugarcane borer resistance and their relation to yield loss[J]. Crop Science, 43: 1729-1735. [63] Moffat A S.2001. Finding new ways to fight plant diseases[J]. Science, 292: 2270-2273. [64] Mohsin A Z, Mojtaba M, Sandra P, et al.2005. The Bt gene cry2Aa2 driven by a tissue specific ST-LS1 promoter from potato effectively controls Heliothis virescens[J]. Transgenic Research, 14: 289-298. [65] Novina C D, Sharp P A.2004. The RNAi revolution[J]. Nature, 430: 161-164. [66] Olivares-Villegas J J, Pierre J, Perroux J, et al.2020. Determination of in-field gene flow between sugarcane cultivars[J]. Tropical Plant Biology, 13: 127-135. [67] Padilla C S, Damaj M B, Yang Z-N, et al.2020. High-level production of recombinant snowdrop lectin in sugarcane and energy cane[J]. Frontiers in Bioengineering Biotechnology, 8: 977. [68] Pawlowski W P, Somers D A.1996. Transgene in heritance in plants genetically engineered by microprojectile bombardment[J]. Molecular Biotechnology, 6(1): 17-30. [69] Piperidis G, Piperidis N, D'Hont A.2010. Molecular cytogenetic investigation of chromosome composition and transmission in sugarcane[J]. Molecular Genetics and Genomics, 284: 65-73. [70] Poovaiah C R, Bewg W P, Lan W, et al.2016. Sugarcane transgenics expressing MYB transcription factors show improved glucose release[J]. Biotechnology and Biofuels, 9: 143. [71] Rathus C, Birch R G.1993. Effects of promoter, intron and enhancer elements on transient gene expression in sugarcane and carrot protoplasts[J]. Plant Molecular Biology, 23: 613-618. [72] Riaño-Pachón D M, Mattiello L.2017. Draft genome sequencing of the sugarcane hybrid SP80-3280[J]. Research, 6: 861. [73] Riaz S, Nasir I A, Bhatti M U, et al.2020. Resistance to Chilo infuscatellus (Lepidoptera: Pyraloidea) in transgenic lines of sugarcane expressing Bacillus thuringiensis derived Vip3A protein[J]. Molecular Biology Reports, 47: 2649-2658. [74] Rossato J A, Costa G H, Madaleno L L, et al.2013. Characterization and impact of the sugarcane borer on sugarcane yield and quality[J]. Agronomy Journal, 105(3): 643-648. [75] Smith N A, Singh S P, Wang N B, et al.2000. Total silencing by intron-spliced hairpin RNAs[J]. Nature, 407: 3 19-320. [76] Spiker S, Thompson W F.1996. Nuclear matrix attachment regions and transgene expression in plants[J]. Plant Physiology, 110: 15-21. [77] Srikanth J, Subramonian N, Premachandran M N.2011. Advances in transgenic research for insect resistance in sugarcane[J]. Tropical Plant Biology, 4: 52-61. [78] Sun Y, Joyce P A.2017. Application of droplet digital PCR to determine copy number of endogenous genes and transgenes in sugarcane[J]. Plant Cell Reports, 36: 1775-1783. [79] Tariq M, Khan A, Tabassum Bet al.2018. Antifungal activity of chitinase II against Colletotrichum falcatum went. causing red rot disease in transgenic sugarcane[J]. Turkish Journal of Biology, 42(1): 45-53. [80] Trujillo L E, Menéndez C, Ochogavía M E, et al.2009. Engineering drought and salt tolerance in plants using SodERF3, a novel sugarcane ethylene responsive factor[J]. Biotecnología Aplicada, 26(2): 168-171. [81] Vain P, James V, Worland B, et al.2002. Transgene behaviour across two generations in a large random population of transgenic rice plants produced by particle bombardment[J]. Theoretical and Applied Genetics, 105(6): 878-889. [82] Van der Geest A H, Welter M E, Woosley A T, et al.2004. A short synthetic MAR positively affects transgene expression in rice and Arabidopsis[J]. Plant Biotechnology Journal, 2: 13-26. [83] Wang M-L, Goldstein C, Su W, et al.2005. Production of biologically active GM-CSF in sugarcane: a secure biofactory[J]. Transgenic Research, 14: 167-178. [84] Wang W Z, Yang B P, Feng X Y, et al.2017. Development and characterization of transgenic sugarcane with insect resistance and herbicide tolerance[J]. Frontiers in Plant Science, 2017, 8: 1535. [85] Wang W Z, Yang B P, Wang J G, et al.2020. Molecular and toxicity analyses of white granulated sugar and other processing products derived from transgenic sugarcane[J]. Frontiers in Plant Science, 11: 596918. [86] Wang Z, Zhang K, Sun X, et al.2005. Enhancement of resistance to aphids by introducing the snowdrop lectin gene gna into maize plants[J]. Journal of Biosciences, 30(5), 627-638. [87] Weng L X, Deng H H, Xu J L, et al.2006. Regeneration of sugarcane elite breeding lines and engineering of stem borer resistance[J]. Pest Management Science, 62:178-187. [88] White W H, Miller J D, Milligan S B, et al.2001. Inheritance of sugarcane borer resistance in sugarcane derived from two measures of insect damage[J]. Crop Science, 41(6): 1706-1710. [89] Xue B, Guo J L, Que Y X, et al.2014. Selection of suitable endogenous reference genes for relative copy number detection in sugarcane[J]. International Journal of Molecular Sciences, 15: 8846-8862. [90] Yao W, Ruan M H, Qin L F, et al.2017. Field performance of transgenic sugarcane lines resistant to sugarcane mosaic virus[J]. Frontiers in Plant Science, 8: 104. [91] Yang Z N, Mirkov T E.1997. Sequence and relationships of sugarcane mosaic and sorghum mosaic virus strains and development of RT-PCR-based RFLPs for strain discrimination[J]. Phytopathology, 87: 932-939. [92] Ye J, Yang Y Y, Xu L P, et al.2016. Economic impact of stem borer-resistant genetically modified sugarcane in Guangxi and Yunnan provinces of China[J]. Sugar Tech, 18(5): 537-545. [93] Yu X H, Wang X H, Yang Q H, et al.2019. Genetic diversity and phylogenetic relationship of Saccharum spontaneum L. with different ploidy levels based on SRAP markers[J]. Sugar Tech, 21(5): 802-814. [94] Zhang J, Cai L, Cheng J Q, et al.2008. Transgene integration and organization in cotton (Gossypium hitsutum) genome[J]. Trangenic Research, 17(2): 293-306 [95] Zhang J S, Nagai C, Yu Q Y, et al.2012. Genome size variation in three Saccharum species[J]. Euphytica, 185(3): 511-519. [96] Zhang J S, Zhang X T, Tang H B, et al.2018a. Allele-defined genome of the autopolyploid sugarcane Saccharum spontaneum L.[J]. Nature Genetics, 50(1): 1565-1573. [97] Zhang Y, Massel K, Godwin I D, et al.2018b. Applications and potential of genome editing in crop improvement[J]. Genome Biology. 19(1): 337-342. [98] Zhou D, Guo J, Xu L, et al.2014. Establishment and application of a loop-mediated isothermal amplification (LAMP) system for detection of cry1Ac transgenic sugarcane[J]. Scientific Reports, 4: 4912. [99] Zhou D G, Wang C F, Li Z, et al.2016a. Detection of bar transgenic sugarcane with a rapid and visual loop-mediated isothermal amplification assay[J]. Frontiers in Plant Science, 7: 279. [100] Zhou D, Xu L, Gao S, et al.2016b. Cry1Ac transgenic sugarcane does not affect the diversity of microbial communities and has no significant effect on enzyme activities in rhizosphere soil within one crop season[J]. Frontier in Plant Sciences, 7: 265. [101] Zhou D G, Liu X L, Gao S W, et al.2018. Foreign cry1Ac gene integration and endogenous borer stress-related genes synergistically improve insect resistance in sugarcane[J]. BMC Plant Biology, 18:342.
