J Plant Biotechnol (2018) 45:190 195 DOI:https://doi.org/10.5010/JPB.2018.45.3.190 ISSN 1229-2818 (Print) ISSN 2384-1397 (Online) Review 세계고구마재배현황및대량생산의선결과제 김호수 이찬주 김소은 지창윤 김성태 김진석 김상용 곽상수 Current status on global sweetpotato cultivation and its prior tasks of mass production Ho Soo Kim Chan-Ju Lee So-Eun Kim Chang Yoon Ji Sung-Tai Kim Jin-Seog Kim Sangyong Kim Sang-Soo Kwak Received: 17 September 2018 / Revised: 17 September 2018 / Accepted: 21 September 2018 c Korean Society for Plant Biotechnology Abstract Sweetpotato [Ipomoea batatas (L.) Lam] represents an attractive starch crop that can be used to facilitate solving global food and environmental problems in the 21 st century. It can be used as industrial bioreactors to produce various high value-added materials, including bio-ethanol, functional feed, antioxidants, as well as food resources. The non-profit Center for Science in the Public Interest (CSPI) announced sweetpotato as one of the ten super foods for better health, since it contains high levels of low molecular weight antioxidants such as vitamin-c, vitamin-e and carotenoids, as well as dietary fiber and potassium. The United States Department of Agriculture (USDA) also reported that sweetpotato is the best bioenergy crop among starch crops on marginal lands, that does not affect food security. The Food H. S. Kim C.-J. Lee S.-E. Kim S.-S. Kwak ( ) 한국생명공학연구원식물시스템공학연구센터 (Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Yuseong, Daejeon 34141, Korea) e-mail: sskwak@kribb.re.kr C. Y. Ji S.-T. Kim ( 주 ) 한국과기산업기업부설연구소 (Research & Development Center, Korea Scientific Technique Industry Co., Ltd., 67, Saneop-ro 92, Gwonseon-gu, Suwon-si 16643, Korea) J.-S. Kim 한국화학연구원친환경신물질연구센터 (Research Center for Eco-Friendly New Materials, Korea Research Institute of Chemical Technology (KRICT), Yuseong, Daejeon 34114, Korea) S. Kim 한국생산기술연구원청정화학응용소재그룹 (Green Chemistry and Materials Group, Korea Institute Technology (KITECH), Cheonan-si, 31056 Chungcheongnamdo, Korea) and Agriculture Organization (FAO) estimated that world population in 2050 will be 9.7 billion, and require approximately 1.7 times more food than today. In this respect, sweetpotato will be a solution to solving problems such as food, energy, health, and environment facing the globe in the 21 st century. In this paper, the current status of resources, and cultivation of sweetpotato in the world was first described. Development of a new northern route of the sweetpotato and its prior tasks of large scale cultivation of sweetpotato, were also described in terms of global food security, and production of high-value added biomaterials. Keywords Sweetpotato, Mass production, Food security, Biomaterials, Marginal land, Genetic resources 서론 산업혁명이후급속한산업화와인구증가는심각한에너지, 환경문제뿐만아니라식량문제, 보건문제를초래하고있다. UN 식량농업기구 (Food and Agriculture Organization, FAO) 는 2050 년세계인구는 97 억명이될것이며지금추세대로에너지와식량을소비하면 2050 년에는에너지는 3.5 ~ 5.5 배, 식량은 1.7 배가필요하다고전망하고있다 (FAO 2015). UN 은지구촌의제반문제를해결하기위하여 3 대환경협약 (1993 년생물다양성협약, 1994 년기후변화협약, 1996 년사막화방지협약 ) 을설립하여노력하여왔다. 그러나 Nature 지는생물다양성협약체결 20 주년이되던 2012 년에그간의노력을분석한결과, 생물다양성은더욱훼손되었고기후변화는더욱심각하고사막화는더욱확산되고있어지속가능한사회발 This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
J Plant Biotechnol (2018) 45:190 195 191 Table 1 Numbers of sweetpotato accessions collected by major organizations Organizations Number of accessions Wild type Cultivars Total CIP, Lima, Peru 1,160 6,360 7,520 ICAR, Kerala, India 84 3,778 3,862 NACRRI, Kampala, Uganda ND 1,808 1,808 NIAS, Tsukuba, Japan ND 1,600 1,600 IABIOGRI, Bogor, Indonesia ND 1.520 1,520 CIP/ESEAP, Bogor, Indonesia ND 1,366 1,366 SRI, Xuzhou, China 40 1,221 1,261 USDA/ARS, Georgia, USA 447 755 1,202 NARI, Kainantu, Papua N. Guinea ND 1,120 1,120 EMBRAPA, Brasilia, Brazil ND 1.024 1,024 Total 1,731 20,552 22,283 전을위해서는특단의노력을하지않으면큰어려움에봉착할것이라경고하였다. 세계 7 대식량작물인고구마 [Ipomoea batatas (L.) Lam] 는전분뿐만아니라바이오에탄올, 항산화물질등각종산업소재를생산하는 21 세기구원투수로등극하고있다 (Kwak et al. 2017a). 미국식품공익단체 (The nonprofit Center for Science in the Public Interest, CSPI) 는비타민 C, 베타카로틴등각종항산화물질, 식이섬유, 칼륨등을고함유하고있는고구마를몸에좋은 10 가지슈퍼식품의첫번째로선정하였다 (CSPI 2007). 미국농업부는 2008 년고구마가밀, 옥수수, 감자, 카사바등전분작물가운데단위면적당가장탄수화물을많이생산하는작물로선정하였고, 식량수급에영향을최소화하는조건불리지역 (marginal land) 에가장적합한바이오에너지작물로발표하였다 (Ziska et al. 2009). 21 세기인류가당면한식량문제를해결하기위해서는행성이아닌지구에서문제해결을모색해야한다. 이러한측면에서사막화가일어나는 ( 반 ) 건조지역, 고염분지역, 오염토양등에비교적잘자라는품종을육성해서활용해야할것이다. 또한고령화에대응하는기능성식품도개발해야한다. 이러한측면에서고구마는글로벌조건불리지역에서고기능성식량자원과바이오소재를생산할수있는구원투수작물로등극이기대된다. 이러한측면에서본논문에서는세계고구마유전자원현황, 고구마재배현황을살펴보고식량, 에너지, 환경, 건강문제를해결하기위한대규모상업적재배가가진문제들에대해살펴보고해결책을제안하고자한다. 세계고구마유전자원현황 고구마는나팔꽃, 메꽃등과 Convolvulaceae 과에속하며재배종은 6 배체 (2n=6x=90) 이다. 4 배체와 2 배체도있지만상업 적인덩이뿌리를형성하지못한다 (Firon et al. 2009). 고구마유전자원은 2009 년현재 29,016 종 ( 야생종 1,948 종, 재배종 27,068 종 ) 이보존되어있는데, 고구마유전자원을가장많이보존하고있는곳은국제감자연구소 (International Potato Center, CIP) 이며약 7,520 종을보유하고있다. 현재는조금증가하였으리라생각되지만큰차이는없을것으로추정된다. 2007 년기준재배종을 1,000 종이상보유하고있는기관들을정리한것이다 (Table 1) (Mok et al. 2009). 이들 10 개기관에서전체의 77% 을보유하고있다. 한국은국립식량과학원고구마연구실에서약 650 계통을보유하고있다. 세계생산의 67% 를차지하는중국은왕성하게고구마신품종을육성하고있으며, 약 2,000 종을보유하고있다고파악되었다 (Personal communications). 세계고구마재배현황 FAO 통계에의하면전세계고구마재배면적은 8,623 천 ha 이며생산량은 105,190 천톤이다 (Table 2) (FAO 2016). 아시아는세계생산의 74.7%(78,595 천톤 ) 을차지하며, 중국은세계생산의 67.3%(70,793 천톤 ) 을생산한다. 인도네시아, 인도, 베트남에서각각 2,270 천톤, 1,472 천톤, 1,269 천톤을생산한다. 아프리카는재배면적은세계의 48.6% 을차지하지만생산량은 20.3% 에지나지않는다. 아프리카의평균생산성 (kg/ha) 은 5,090 kg 으로낮은이유는병충해에의한피해와적정재배기술이도입되지않은것으로추정된다. 아시아국가의생산성은 20,082 kg 이지만, 필리핀, 베트남등은비교적낮다. 한국고구마재배현황 현재국내고구마생산량은약 30 만톤으로식량이부족한 1960 년도약 300 만톤생산에비하면 10% 에지나지않는다.
192 J Plant Biotechnol (2018) 45:190 195 Table 2 Cultivation area and production of sweetpotato in major countries (FAO 2016) Nation Cultivation area (1,000 ha) Productivity (kg/ha) Production (1,000 ton) World 8,23 (100.00) 12,198 (100.00) 105,190 (100.00) Asia 3,913 (45.38) 20,082 (164.64) 78,595 (74.72) China 3,291 (38.17) 21,511 (176.36) 70,793 (67.30) Indonesia 137 (1.59) 16,567 (135.82) 2,270 (2.16) India 130 (1.51) 11,323 (92.83) 1,472 (1.40) Vietnam 120 (1.39) 10,522 (86.26) 1,269 (1.21) Philippines 84 (0.97) 6,247 (51.22) 529 (0.50) Japan 36 (0.42) 23,908 (196.01) 860 (0.82) North Korea 32 (0.37) 13,590 (111.41) 436 (0.41) South Korea 20 (0.23) 14,513 (118.98) 295 (0.28) Africa 4,187 (48.56) 5,090 (41.73) 21,316 (20.26) Tanzania 759 (8.80) 5,033 (41.26) 3,822 (3.36) Uganda 482 (5.59) 4,411 (36.16) 2,126 (2.02) Mozambique 52 (0.60) 13,808 (113.21) 730 (0.69) Table 3 Comparison of sweetpotato and rice in terms of cultivation area, production, retail price and farm income in 1965, 1991 and 2016 (modified from Statistics Korea, www.kostat.go.kr) Year 1965 1991 2016 Crop Cultivation area (1,000 ha) Production (1,000 ton) Retail price (Won/kg) Farm income (1,000 Won/10a) rice 1,240 3,500 60 <16 Sweet potato >127 >2,600 ND ND rice 1,200 5,380 1,400 410 Sweet potato 170 380 127 <100 rice 790 4,200 2,000 430 Sweet potato 230 340 4,400 1,770 과거부자들은쌀을선호하였으나지금은고구마를선호하고있다. 국내고구마와쌀생산량, 가격등을통계청농산물유통정보자료를편집하여정리하면 Table 3 과같다 (KAMIS 2016; Statistics Korea 2016). 고구마의생산량은현저히감소하였지만소매가격은높은수준으로증가하여 2016 년기준 10a 당고구마의농가소득 (177 만원 ) 은쌀 (43 만원 ) 농가소득에비해약 4.1 배높음을알수있다. 고구마의 2016 년기준총생산액 ( 생산량 소매가격 ) 은약 1 조 5 천억원에달하는것을알수있다. 또한고구마를이용한가공식품의가격은매우높아이로부터파생되는시장가치는매우높을것으로예상된다. 국내생고구마는자급되지만, 고구마전분, 당면등은중국등에서수입되고있어수입되는고구마전분, 당면등을고려하면우리나라고구마자급률은 30 ~ 40% 수준으로평가된다. 향후검역에문제가없을정도로깨끗한고구마가중국에서수입될수있어국제적으로경쟁력있는고구마생산기반을시급히확보할필요가있다. 2007 년서울대학교농업생명과학정보원은우리나라농 림수산 R&D 투자실적분석에서 33 개주요농산물가운데고구마는투자금액이 24 위인데비하여생산액에서는작물가운데쌀다음으로약 3,008 억원으로높았다. 고구마는국민이좋아하고농민이선호하는작물인점을고려한다면연구개발에보다많은투자를할필요가있다. 고구마의새로운북방로드개척 농경지가부족한한국이낮은곡물자급률 (2016 년 24%) 을해결하기위해서는국내농지의생산성제고만으로식량자급률을높이기에는한계가있다. 산업화로농지가감소하고있는현실에서자급률유지도쉽지않을것이라는점을고려한다면, 해외농업을적극적으로추진해야한다. 그러나비옥한해외농지를이용하기에는어려움이많기때문에일본등다른국가들과차별화되면서미래지향적인해외농업을고려한다면동북아시아, 중앙아시아, 중동, 북부아프리카등의조건불리지역에도전하는고구마북방로드를적극적으로개척할필요가있다 (Fig. 1).
J Plant Biotechnol (2018) 45:190 195 193 상업적고구마대량재배의선결과제 단위면적당탄수화물생산, 기능성식품측면에서준완전식품으로인정받고있는고구마가밀, 옥수수, 감자등다른작물보다경쟁력을갖고상업적으로양산하기위해서는다음의문제가해결되어야할것이다 (Kwak et al. 2017; Yamakawa 2017). Fig. 1 New sweetpotato northern road for sustainable development in the future. Each red dot represents 1,000 ha. This figure was obtained from Prof. Qingchang Liu, China Agricultural University 한국생명공학연구원은중국내몽고자치구쿠부치사막인근지역과카자흐스탄여러지역에고구마를시범재배한결과고구마를보다높은수량으로생산할수있음을확인하였다. 특히카자흐스탄은 2014 년부터 3 년간카자흐스탄 4 개지역에 10 품종을시범재배한평균결과에서남부알마티지역에서 ha 당 38 ~ 41 톤의고구마가생산되는것을확인하였다 (Table 4) (Kwak et al. 2017a). 우리나라수확량이약 15 톤인것에비하면매우높은생산량이며적정재배기술을도입하면 40 톤이상생산할수있을것으로기대된다. 동북아시아중앙아시아의척박한지역에적합한품종을생명공학기술로개발해식물조직배양기술로무균묘를생산하여기계화농사법을도입하면비교적낮은가격으로전분을생산할수있을것이며고구마기반기축전분이확립될수있을것으로기대된다. 고구마는서리가내리지않은날 ( 무상일수, frostfree day) 이 4 개월이면어느곳에서도재배될수있으며고위도지역일수록수확량이높다. 이들지역에서고구마수확량이높은이유는은병충해가거의없으며덩이뿌리의비대기인가을철의밤낮온도차이가높아낮에광합성산물이밤에따뜻한지하부로이동하기때문이다. 1) 고구마심는방법을자동화해야한다. 지금의삽식묘 (25cm 전후 ) 는생산하는데공간과비용이많이소요될뿐만아니라심는과정에많은시간과노동력을요구한다. 어떻게심는방법을자동화할것인가 가대량재배에가장중요하다. 아직까지고구마는구황작물이라는인식으로인해기업의관심이보다적고기계화재식의필요성에대한인식이부족하여아직해결되지못한문제라판단된다. 이러한관점에서저자들은 삽식용고구마줄기대용씨고구마대량생산방법 을연구하고있다 (Kwak et al. 2018). 현재농림축산식품부농생명산업기술개발사업에서벼농사대체용고구마품종육성및생력화기술개발사업에서고구마심는방법을더욱개선하는연구를수행중에있다. 2) 관행고구마품종육성방법을포함하여적극적으로해당지역용도에맞는품종을개발해야한다. 특히고구마는척박한토양에서도어느정도수량을보장하기때문에생명공학기술로품종을개량하면척박한토양에서도잘자라고고부가가치바이오소재를양산할수있을것이다 (Kim et al. 2009a, 2009b). 전분등을생산하는산업용고구마인지, 건강을위한식용고구마인지에따라품종육성방법이달리고려돼야할것이다. 전분을생산하기위해서는전분대사공학으로전분의조성을조절할수있다 (Ahn 2009). 저자들은카로티노이드를축적하는고구마 Orange (IbOr) 유전자를분리하여형질전환고구마를개 Table 4 Cultivation of 10 sweetpotato cultivars in four different s of Kazakhstan Cultivars Akmolinskaya Karagandinskaya South Kazakhstan Almatinskaya K2 17.6 18.0 - - K5 29.3 28.9 - - K10 28.7 29.6 - - K12 - - 32.1 33.0 K13 - - 33.3 32.6 K14 - - 38.1 35.6 K20 - - 41.1 38.0 P1 17.9 17.3 - - P2 29.4 26.1 - - F1 - - 35.2 19.7
194 J Plant Biotechnol (2018) 45:190 195 발한결과, 47 고온에서도정상적인생육을하면서베타카로틴등을고생산하는것을확인한바있다 (Kim et al. 2013; Park et al. 2016; Kang et al. 2017a, 2017b; Kim et al. 2018). 현재 IbOr 유전자의변이체를이용한형질전환고구마, 벼등을개발하고있다 (Kwak et al. 2017b). 3) 고구마를양산하여연중이용하기위해서는저온저장성향상을위한방법이개선돼야한다. 고구마는수확후 13 ~ 15 C 저온과 85% 이상의높은습도조건에서저장해야한다. 지하저장고, 터널을만드는기술이발전되어물리적인방법에서고구마저장성문제도해결할수있지만, 생명공학기술을이용하여저온에대한고구마저장성원인을규명하고저온저장성과저온내성증가를위한연구가진행되고있다 (Ji et al. 2017; Jin et al. 2017; Ji 2018) 4) 고구마를조건불리지역에서염가로양산하여고구마전분, 당에서고부가가치바이오소재를생산하고새로운용도를개발에관한연구를수행할필요가있다. 이러한관점에서국가과학기술연구회다학제융합클러스터에서저자들은 고구마기반글로벌식량자원및바이오소재생산기술 에필요한기획과제를준비하고있다 (SBFC 2017). 글로벌조건불리지역에서고구마를양산하면식량, 사료, 고부가가치바이오소재뿐만아니라탄소배출권도확보할수있어블루오션을개척할수있을것이다. 적요 고구마는 21 세기인류가당면한식량, 에너지, 환경, 보건문제등을해결하는 21 세기구원투수로등장하고있다. 고구마는식량자원뿐만아니라바이오에탄올, 기능성사료, 항산화물질등고부가가치소재를생산하는생체반응기로평가된다. 미국공익과학단체 (The nonprofit Center for Science in the Public Interest, CSPI) 는고구마가저분자항산화물질, 식이섬유, 칼륨등을고함유하고있는고구마를몸에좋은 10 대슈퍼식품가운데하나로선정하였다. 미국농무부는고구마를전분작물가운데식량수급에영향을최소화하는척박한토양에가장적합한바이오에너지작물로평가하였다. UN 식량농업기구는 2050 년에세계인구가 97 억명이될것이며지금추세로식량을사용하면 2050 년에는지금의 1.7 배의식량이필요하다고전망했다. 어떻게미래식량위기를극복할것인가? 이러한측면에서척박한토양에서도어느정도수량을보장하는고구마가지구가당면한제반문제를해결할수있을것으로기대된다. 본논문에서는세계고구마유전자원과생산현황을살펴보고, 글로벌식량자원및고부가가치바이오소재측면에서새로운고구마의북방로드개척및상업적대량재배를위한선결과제를기술하고자한다. 사사 본연구는농림축산식품부농림식품기술기획평가원의농생명산업기술개발과제 벼농사대체용고구마품종육성및생력화기술개발 (118038-3), 국가과학기술연구회 (NST) 다학제융합클러스터 고구마기반글로벌식량자원및바이오소재생산기술 (CCL-17-01-KRIBB), 농촌진흥청차세대바이오그린 21 사업 (PJ01318401) 에서지원되었다. References Ahn YO, Yang KS, Kwak SS, Lee HS (2009) Current status on metabolic engineering of starch in sweetpotato. J Plant Biotechnol 36:207-213 CSPI (The Center for Science in the Public Interest) (2007) 10 Best Foods. https://cspinet.org/eating-healthy/what-eat/10-best-foods Firon N, Labonte D, Villordon C, McGregor C, Kfir Y, Pressman E (2009) Botany and physiology: storage root formation and development. In, The Sweetpotato (edited by Loebenstein and Thottappilly G). Springer. pp 13-26 FAO (Food and Agriculture Organization of the United Nations) (2015) The state of food insecurity in the world, 8-18 http:// www.fao.org/home/en/ Ji CY (2018) Molecular and physiological studies on tuberous roots of sweetpotato under low temperature storage. Ph.D thesis. University of Science and Technology (UST). February 2018. pp. 124 Ji CY, Chung WH, Kim HS, Jung WY, Kang L, Jeong JC, Kwak SS (2017) Transcriptome profiling of sweetpotato tuberous roots during low temperature storage. Plant Physiol Biochem 112: 97-108 Jin R, Kim BH, Ji CY, Kim HS, Li HM, Ma Daifu, Kwak SS (2017) Overexpressing IbCBF3 increases low temperature and drought stress tolerance in transgenic sweetpotato. Plant Physiol Biochem 118:45-54 KAMIS (2016) https://www.kamis.or.kr/customer/main/main.do Kang L, Kim HS, Kwon YS, Ke Q, Ji CY, Park SC, Lee HS, Deng X, Kwak SS (2017a) IbOr regulates photosynthesis under heat stress by stabilizing IbPsbP in sweetpotato. Front Plant Sci 8, 989 Kang L, Park SC, Ji CY, Kim HS, Lee HS, Kwak SS (2017b) Metabolic engineering of carotenoids in transgenic sweetpotato. Breeding Sci 67:27-34 Kim MD, Ahn YO, Kim YH, Kim CY, Lee JJ, Jeong JC, Lee HS, Mok IG, Kwak SS (2009a) Strategies of development of environmentally friendly industrial sweetpotato on marginal lands by molecular breeding. J Plant Biotechnol 36:197-201 Kim HS, Ji CY, Lee CJ, Kim SE, Park SC, Kwak SS (2018) Orange: a target gene for regulating carotenoid homeostasis and increasing plant tolerance to environmental stress in marginal lands. J Exp Bot 69:3393-3400
J Plant Biotechnol (2018) 45:190 195 195 Kim SH, Ahn YO, Ahn MJ, Jeong JC, Lee HS, Kwak SS (2013) Cloning and characterization of an Orange gene that increases carotenoid accumulation and salt stress tolerance in transgenic sweetpotato cultures. Plant Physiol Biochem 70:445-454 Kim YH, Park SC, Yang GS, Zhou Z, Zhao D, Ma D, Jeong JC, Lee HS, Kwak SS (2009b) Selection of oxidative stress-tolerant sweetpotato cultivars for cultivation on marginal lands. J Plant Biotechnol 36:219-223 Kwak SS, Park SC, Mok IG (2017a) Sweetpotato as a reliever in 21 st century. KFSRF (in Korean). pp. 155 Kwak SS, Kim JW, Min JK, Kim HS (2018) Method for producing seedling and seed of sweetpotato from sterile sweetpotato stem by tissue culture. Patent application No 10-2018-0030059 (March 15, 2018) Kwak SS, Kim HS, Kim SE. Lee CJ, Ji CY (2017b) IbOr-R96H mutant from Ipomoea batatas and uses thereof. Patent application No 10-2017-0175023 (December 19, 2017) Mok IG, Zhao DR, Kwak SS (2009) Genetic resources of sweetpotato for industrial use. J Plant Biotechnol 36: 202-206 Park S, Kim HS, Jung YJ, Kim SH, Ji CY, Wang Z, Jeong JC, Lee HS, Lee SY, Kwak SS (2016) Orange protein has a role in phytoene synthase stabilization in sweetpotato. Sci Reports 6: 33563 SBFC (Sweetpotato Biomaterials Fusion Cluster) (2017) Sweetpotato based global food resource and biomaterial production technology. Newsletter Vol. 1 (July 76, 2017), pp 4 Statistics Korea (2016) http://kostat.go.kr/portal/korea/index.action Yamakawa O (2017) The world of sweetpotato, the sweetpotato of world. Gendaishokan (in Japanese). pp 243 Ziska LH, Runion GB, Tomecek M, Prior SA, Torbet HA, Sicher R (2009) An evaluation of cassava, sweetpotato and field corn as potential carbohydrate sources for bioethanol production in Alabama and Maryland. Biomass Bioenergy 33:1503-1508