韓國際農誌 (Korean J. Intl. Agri.), 24(1): 70~75(2012) 호밀과헤어리베치의단파및혼파가 신고 배의양분공급량과생육에미치는영향 임경호 최현석 * 나양기 ** 송장훈 조영식 최장전 최진호 정석규 *** 국립원예특작과학원배시험장, * 국립농업과학원유기농업과, ** 전라남도농업기술원, *** 경희대학교한방재료가공학과 Nutrient Contribution and Growth of Niitaka Pear Trees as Affected by Mix-Seeding and Single-Seeding of Rye and Hairy Vetch Kyeong-Ho Lim, Hyun-Sug Choi*, Yang-Gi Na**, Jang-Hoon Song, Young-Sik Cho, Jang-Jeon Choi, Jin-Ho Choi, and Seok-Kyu Jung*** Pear Research Station, National Institute of Horticultural & Herbal Science, Naju, 520-821, Republic of Korea *Organic Agriculture Division, National Academy of Agricultural Science, Suwon, 441-707, Republic of Korea **Jeollanam-do Agricultural Research & Extension Services, Naju, 520-715, Republic of Korea ***Department of Oriental Medicinal Materials & Processing, Kyung Hee University, Yongin 446-701, Republic of Korea ABSTRACT: This study was conducted to evaluate the effects of mix- and single-seeding of green manure crops, such as rye and hairy vetch, on the nutrient contribution and growth of 'Niitaka' (Pyrus pyriforia L.) pear trees, in order to develop utilization of green manure crops as an organic nutrient source in a pear orchard. The experiment was conducted at an organic orchard in Boseong in Chonnam Province, Republic of Korea, and the treatments followed as; 1) sod culture, 2) rye (16 kg/10a), 3) hairy vetch (5 kg/10a), and 4) rye (6.4 kg/10a) + hairy vetch (3 kg/10a), which were sown on the orchard floor on October of 2007. Mix-seeding of rye and hairy vetch resulted in higher number of shoots than singleseeding of rye or hairy vetch. Sod culture produced 362 kg/10a of dry weight, which was lower than those of plots treated with mix-seeding of rye and hairy vetch (856 kg/10a). Mix-seeding treatment produced 13.9 kg/10a of N from raw materials in the green manures, which was 2.1 times greater than those of the sod culture. Mix-seeding increased both P and K productions and satisfied the amounts of N (10kg/10a), P (2kg/10a), K (7kg/10a) for 10-12 year-old pear tree growth. Sod culture treatment increased bulk density but decreased porosity. Concentrations of foliar N, P, and K in pear trees increased from May to July after vegetation around trees were mowed. There were non-significant differences for fruit quality amongst the plots treated with green manure crops. Key words: fruit quality, green manure crops, organic nutrient, pear, seeding method 배과수원의표준시비량 (10~14년생수령 ) 은질소-인산-칼륨이각각 10-2-7kg/10a 으로그중밑거름은낙엽기부터휴면기중에시용되는비료로질소는연간시비량의 50~70%, 인산은 100%, 칼륨은 50~60% 를시용하고나머지는웃거름으로시용한다 (Environmental-Friendly Agriculture Research Center, 2010). 배재배면적은 17,090 ha이고생산량은 418,368 ton으로과수에서사과와감귤다음으로많은작목이다 (KREI, Corresponding author: (Phone) +82-31-290-0544 (E-mail) dhkdwk7524@daum.net <Received Jan. 4, 2012 / Revised Feb. 23, 2012 / Accepted Mar. 14, 2012> 2009). 전남지역의배친환경인증농가수는 1,211 농가로그수가급격한증가추세에있으나대부분이저농약단계에머물러있다. 이러한이유는아직유기재배에알맞은시비관리체계와화학비료와합성농약대체기술이정립되어있지않기때문으로사료된다. 일반적으로배과수원에서유기질비료는화학비료에비해각종미량원소등이풍부해서양분공급효과 (Ju & Im, 2004) 가크지만, 과다한축분퇴비시용등은토양내로의질산태질소나인산또는중금속의축적등과같은문제를일으킬수있으므로적절한유기질양분시용에대한주의가필요하다 (Chung & Lee, 2008). 독일의유기농법은토양비옥도를유지증진시키기위하여화 70
71 韓國際農誌 (Korean J. Intl. Agri.), 24(1), 2012 학적으로합성된화학비료를사용하지않고녹비작물특히클로버와같은사료작물을작부방식에서 30% 의비중을두어재배하고있다 (Chang & Sohn, 1999). 미국캘리포니아지역과수원의피복작물재배농가중 69% 가동계피복작물을재배하는데이용목적은수체생장을위한질소성분을얻기위함이다 (Song, 2001). 미국남부지역사과과원의초생실험에서일반방임초생도 3년차에적절한무기성분을토양내로환원시켜서건전한수체생장과광합성증가에영향을미쳤음을알수있었다 (Choi et al., 2011a; Choi et al., 2011b). 질소공급이좋은헤어리베치와토양물리성개선에효과적인호밀의혼용은배과수원의토양환경을개선하여수체생장과과실품질향상에효과적일수있다. 이전실험에서가을용녹비작물인호밀과헤어리베치를시기별 (9월중순, 10월중순, 11 월중순, 12월중순 ) 로단용시비하였을때파종시기가빠를수록양분공급량에효과적인것으로확인되었다 (Lim et al., 2011). 따라서가장효과적인파종시기인 10월초에이러한녹비작물을혼용처리하였을때양분공급량과배나무생육에어떠한영향을미치는지에대한연구가요구되고있다. 본연구는 신고 배과수원에화학비료대체를위한녹비작물로서호밀과헤어리베치를파종하였을때토양에무기성분환원량을추정하고이에따른수체생장에미치는영향을구명하고자수행되었다. 재료및방법 1. 시험장소및과원특성본연구는전남보성의독농가에서 2004년에유기농으로인증된과원에서수행하였다. 호밀과헤어리베치의파종시기에따른녹비작물의생육과양분공급량에미치는영향 (Lim et al., 2011) 에관한연구와연계되는시험으로수령은 10~12년생의덕식수형인 67 m 신고 (Pyrus pyriforia L.) 배나무를이용하였고수관하부는자연방임초생으로잡초를관리하였다. 표토의토성은양토이고심토는식양질로자갈함량이적은과원이었다. 녹비작물수확전 (2008년 4월 ) 평균토양 ph는 5.8, 유기물함량은 4.5%, 전질소는 0.26%, 인산은 268 mg/kg, 칼륨은 1.7 cmol + /kg, 칼슘은 6.0 cmol + /kg, 마그네슘은 3.3 cmol + /kg 으로관찰되었다. 실험수행연도인 2008년에강수량은 960 mm 이고평균기온은 14.5 o C로평년평균 ( 강수량, 1,450 mm; 기온, 12.6 o C) 보다다소고온건조하였다. 2. 실험처리처리내용은녹비작물파종방법에따라서네가지로나누었으며, 1) 방임초생 ( 대조구 ), 2) 호밀 (16kg/10a) 단파, 3) 헤어리베치 (5 kg/10 a) 단파, 4) 호밀 (6.4 kg/10 a) + 헤어리베치 (3.0 kg/ 10 a) 혼파로나누어서 2007년 10월 15일에처리하였다. 처리는 1주 1반복으로완전임의배치법 5반복으로처리하였다. 2008년 4월 21일에녹비작물을단위면적당 (m 2 ) 수확해서신선중과건물중을측정하였다. 녹비작물수확시로타리로경운하여잔사를환원하지않고그대로지표면위에두어서자연고사시켰다. 녹비작물양분급원으로모든처리구에유기질쌀겨 (250kg/10a) 를매년봄철에시용하였고쌀겨의전질소농도는 2.1%, 인산은 3.8%, 칼륨은 1.4% 로조사되었다. 3. 분석방법채취한녹비작물을비이온성세제로세척한후무기성분을분석하였다. 세척된녹비작물을 70 o C의온풍건조기에서 3일간건조시킨후마쇄하여토양및식물체분석법 (RDA, 2000) 에준하여식물체내무기성분을조사하였다. 전질소는황산으로분해후 Kieldahl법으로, 인산은 ammonium metavandate 비색법에의해서정량하였다. 칼륨은 ternary 용액 (HNO 3 : H 2 SO 4 :HClO 4, 10 : 1 : 4, v/v/v) 을이용하여열판에서가열분해한후 Inductively Coupled Plasma Atomic Emission Spectrometer(ICP-AES, PU 9000, Pye-Unicam Ltd., Cambridge, England) 로측정하였다. 토양물리성은수관하부주간으로부터 1.5m 떨어진곳 (10cm 깊이 ) 에서 soil core( 용량 100mL) 로채취한토양을이용하였다. 배나무잎은 Westwood(1993) 방법에따라 5월27일과 7월1 일에당해연도에자란신초들에서중간정도의위치에있는잎을주당 50매정도를임의로채취하였다. 수확한잎은실험실내온풍건조기 (70 o C) 에서 3일간건조시켰다. 건조후무기성분은앞에서언급한식물체분석법에따라분석하였다. 수확한과실은전자저울 (AR-2130, USA) 로신선중을측정하고, 가용성고형물함량은굴절당도계 (Refractrometer, Atago, Japan) 로과실에서착즙한과즙을측정하였다. 과실경도는과실중간부위면에서과피를제거한후과실경도계 (TA- XT2, Texture technologies Corp., Scarsdale, NY, USA) 로측정하였다. 과피색은과실색차계 (Minolta CR-300, Japan) 로측정하여 Hunter value L *, a *, b * 값으로표시하였다 (L *, 과실의밝기 ; a * 와 b *, 각각과실의적색과황색의정도 ). 결과및고찰 호밀의생육은호밀단파또는혼파처리에따라초장과엽수는별다른차이는없었지만줄기수는호밀단파처리 (844개 /m 2 ) 가혼파처리 (519개 /m 2 ) 보다더많았다 (Table 1). 헤어리베치의경우는헤어리베치단파로처리하였을때초장과엽수는혼파처리보다는적었지만줄기수는오히려증가하였다. 이러한생육의차이는건물중의차이로이어졌는데, 호밀단파처리는 811 kg/10 a의건물중을, 헤어리베치단파는 239 kg/ 10 a의건물중을나타내었고, 이들은각각의혼파처리 (856 kg/ 10 a) 보다모두낮았다 (Table 2). 이러한이유는헤어리베치생육형태로유추해볼수있는데, 지표면위에서의생장에그치
호밀과헤어리베치의단파및혼파가 신고 배의양분공급량과생육에미치는영향 72 Table 1. Growth characteristics by mix- and single-seeding of rye and hairy vetch. Rye Vetch Height (cm) Leaf (No/plant) Stem (No/m 2 ) Height (cm) Leaf (No/plant) Stem (No/m 2 ) Rye 134 ± 1.9 y 4.9 ± 0.3 844 ± 170 - - - Vetch - - - 54.3 ± 1.3 9.1 ± 0.4 408 ± 52 Rye+vetch 143 ± 5.8 4.8 ± 0.2 519 ± 92 83.7 ± 9.2 10.5 ± 0.4 197 ± 80 Table 2. Dry weight as affected by mix- and single-seeding of rye and hairy vetch. Dry weight (kg/10a) Rye Vetch Vegetation Total Sod culture - - 362 ± 40 y 362 ± 40 Rye 818 ± 136 - - 811 ± 136 Vetch - 239 ± 16-239 ± 16 Rye + vetch 687 ± 166 169 ± 53-856 ± 304 는헤어리베치단파와는달리헤어리베치혼파처리는헤어리베치가호밀의줄기위까지성장함으로써건물중을증가시킨것으로판단되었다. 또다른이유로는혼파처리의파종량 ( 호밀 (6.4 kg/10 a) + 헤어리베치 (3.0 kg/10 a)) 이헤어리베치 (5 kg/10 a) 단파처리보다는높았기때문으로사료된다. 한편관행방임초생은 362 kg/10 a의건물중으로헤어리베치단파처리보다는높았는데, 이는헤어리베치의예초시기가다소빨라나타난결 과로사료된다. 하지만방임초생은두초종의혼파처리보다는 2.4배낮은건물중을보였다. 초종별전질소 (T-N) 농도는녹비파종방법 ( 단파 / 혼파 ) 에따라서별다른차이가없었는데, 호밀의전질소농도는호밀단파처리에서 0.9% 로혼파처리 (1.1%) 보다는낮았고헤어리베치는헤어리베치단파처리 (3.9%) 가혼파 (3.6%) 보다는다소높은경향을나타내었다 (Table 3). 헤어리베치는질소고정초종으로서질소농도가일반적으로높고 (Seo & Lee, 2005; Lim et al., 2011), 호밀은단위면적당건물중을증가시켜서질소농도가다소낮게나타난것으로추정되기도 (Faust, 1989) 하나, 호밀의식물특성 ( 화본과작물로낮은무기성분농도 ) 자체에기인한것으로판단된다. 질소환원량은녹비파종처리가방임초생보다모두높았으며, 두녹비작물의혼파가 13.9kg/10a를토양에환원시킴으로서관행대비 2.1배높게나타났다. 파종방법에따른초종별인산 (P) 농도는별다른차이가없었으며호밀이헤어리베치보다낮은인산농도를나타내었다 (Table 4). 인산환원량은호밀단파또는혼파처리에서각각 Table 3. N concentration and estimated N production as affected by mix- and single-seeding of rye and hairy vetch. T-N (%, dry wt.) T-N (kg/10a) Rye Vetch Vegetation Rye Vetch Vegetation Total Sod culture - - 1.8-6.5 ± 0.7 y 6.5 ± 0.7 Rye 0.9 - - 8.2 ± 1.3 - - 8.2 ± 1.3 Vetch - 3.9 - - 9.2 ± 0.6-9.2 ± 0.6 Rye+vetch 1.1 3.6-7.8 ± 1.9 6.11 ± 1.9-13.9 ± 1.9 Table 4. P concentration and estimated P production as affected by mix- and single-seeding of rye and hairy vetch. P (%, dry wt.) P (kg/10a) Rye Vetch Vegetation Rye Vetch Vegetation Total Sod culture - - 1.1 - - 3.9 ± 1.6 y 3.9 ± 1.6 Rye 0.7 - - 5.9 ± 0.9 - - 5.9 ± 0.9 Vetch - 1.2-2.9 ± 0.2-2.9 ± 0.2 Rye + vetch 0.6 1.2-4.1 ± 1.0 2.0 ± 0.6-6.1 ± 1.1
73 韓國際農誌 (Korean J. Intl. Agri.), 24(1), 2012 Table 5. K concentration and estimated K production as affected by mix- and single-seeding of rye and hairy vetch. K (%, dry wt.) K (kg/10a) Rye Vetch Vegetation Rye Vetch Vegetation Total Sod culture - - 3.1 - - 11.2 ± 1.2 y 11.2 ± 1.2 Rye 1.8 - - 15.8 ± 2.4 - - 15.8 ± 2.4 Vetch - 4.0 - - 9.5 ± 0.6-9.5 ± 0.6 Rye + Vetch 2.3 4.1-15.8 ± 3.8 6.9 ± 2.2-22.8 ± 3.1 Table 6. Soil physical properties as affected by mix- and single-seeding of rye and hairy vetch. Bulk density (Mg/m 3 ) Particle size (%) Solid phase Liquid phase Air phase Porosity (%) Sod culture 1.34 a y 51 a 26 a 23 c 49 c Rye 1.02 c 39 c 21 b 40 a 61 a Vetch 1.05 c 40 c 23 b 38 a 60 a Rye+vetch 1.21 b 46 b 24 ab 31 b 54 b P value < 0.01 < 0.01 < 0.05 < 0.001 < 0.01 y Means separation within columns by Duncan's multiple range test at p0.05, n=5. 5.9와 6.1 kg/10a로높게나타났다. 헤어리베치단파처리 (2.9 kg/10a) 는방임초생재배 (3.9 kg/10a) 보다오히려낮은인산환원량을나타내었는데이는일반자연초종과비교하여낮은건물중과비슷한인산농도를나타내었기때문이다. 녹비작물의칼륨 (K) 농도는전질소와인산과마찬가지로파종방법에상관없이헤어리베치가호밀보다높았다 (Table 5). 칼륨환원량은혼파처리에서 22.8 kg/10a으로가장높았고, 인산환원량이가장낮았던헤어리베치단파가 9.5 kg/10a로역시낮게나타났다. 방임초생재배구는토양용적밀도 (1.34 Mg/m 3 ) 와고상 (51%) 이높아서공극율 (49%) 이낮은것으로관찰되었다 (Table 6). 호밀은주당 600 km에이르는근모를가지고있어서토양물리성개선에효과적인것으로알려져있는데 (Faust, 1989), 본시험에서는헤어리베치와비슷한물리성개선효과가관찰되었다. 두초종의단파처리는혼파처리보다낮은용적밀도와높은공극률을나타내었다. Faust(1989) 는시비량이증가하면지상부생장을증가시켜뿌리생장을억제한다고하였는데, 지상부생육을증가시킨혼파처리가뿌리생장을상대적으로감소시켜토양물리성을크게증진시키지못하였던것으로추정된다. 본실험에서는녹비작물의지하부생육을확인하지못하였는데, 앞으로이에대한검증이필요할것으로판단된다. 또한두초종간의뿌리의타감작용 (allelopathy) 은지하부생육을감소시켜 (Faust, 1989) 토양물리성에영향을미쳤을것으로추정되지만이에대한과학적검증또한요구된다. 5월의배나무잎의질소농도는방임초생재배와헤어리베 Table 7. Foliar N, P, and K concentrations in pear trees as affected by mix- and single-seeding of rye and hairy vetch. Nutrient concentration (%, dry wt.) T-N P K 27 May Sod culture 1.91 a y 0.41 0.98 b Rye 1.71 b 0.42 1.05 b Vetch 1.89 a 0.39 1.08 b Rye + vetch 1.76 ab 0.40 1.39 a P value < 0.05 0.632 < 0.05 1 July Sod culture 3.27 0.34 b 1.12 Rye 3.27 0.37 a 0.98 Vetch 3.41 0.37 a 1.11 Rye + vetch 3.28 0.38 a 1.19 P value 0.229 < 0.01 0.652 y Means separation within columns by Duncan's multiple range test at p0.05, n=5. 치구에서높았으며인산은처리간에별다른차이가없었다 (Table 7). 봄철에호밀과혼파처리는토양내물과양분흡수를증가시켜높은건물중을생산함으로써 (Table 2) 상대적으로토양내적은양의양분이용도에따른배나무잎의농도감소로
호밀과헤어리베치의단파및혼파가 신고 배의양분공급량과생육에미치는영향 74 Table 8. Fruit quality of pear trees as affected by mix- and single-seeding of rye and hairy vetch. Weight (g) Soluble solids content ( o Bx) Firmness (N) Hunter value L * a * b * Sod culture 499 y 11.7 23.1 58.1 4.44 35.1 Rye 486 11.3 23.0 57.2 2.95 34.2 Vetch 499 11.5 20.9 57.3 3.91 34.7 Rye+vetch 532 11.2 24.1 57.7 2.71 34.5 P value 0.466 0.321 0.934 0.607 0.189 0.252 y Means separation within columns by Duncan's multiple range test at p0.05, n=5. L *, a *, and b * refer to lightness, red color, and blue color, respectively. 추정된다. 칼륨은녹비작물혼파처리 (1.39%) 에서높게나타났다, 7월의엽분석에서는질소와칼륨농도는처리간에별다른차이가없었고인산은방임초생재배구에서가장높았다. 기존에보고된관행재배된배나무잎의시기별무기성분이동에서재배초기 (4~5월 ) 에질소와인산그리고칼륨농도는재배후기 (7~8월) 보다높았는데 (Buwalda & Meekings, 1990), 이는질소, 인산, 칼륨이식물체내에서이동성이매우빠르게대사작용이왕성한곳 ( 어린잎이나생장분열조직 ) 으로이동하는원소이기때문이다 (Faust, 1989). 따라서재배후기에는그러한무기성분농도가감소한것으로알려졌다. 이러한다량원소의식물체내이동성은유기재배된사과과수원에서도비슷한경향이나타났다 (Choi et al., 2011a; Choi et al., 2011c). 하지만본실험에서는 5월 27일에채취한잎의질소농도가 7월 1일에채취한잎보다낮게관찰되었다. 그러한이유는명확하지않지만, 다만 4월하순에예초된초생이토양환원후에부숙이진행되고나서무기태질소가서서히배나무로흡수되어 7월에배나무잎의질소농도증가에기여했을것으로추정된다. 과실품질은초생처리간에별다른차이가관찰되지않았다 (Table 8). 이러한차이가녹비작물처리에따른것인지, 환경요인이작용하였는지를판단하기위해서는보다더장기간 (multiple year) 시험이요구된다. 과실무게와당도및경도는기존에알려진 신고 배와유사하였다. 하지만과실특성은앞에서언급한바와같이전년도의관리상태에따라영향이크게달라짐으로당년에판단하는것은다소무리가있으므로최소한 3년이상의연구가필요할것으로판단되었다. 뉴질랜드사과과원에서보고된자료에의하면식물체잔사를토양표토내부에묻고 3개월후잔사의건물중과질소농도를측정하였을때대부분의무기태질소는토양내부로공급되고 20% 이하만잔사로남아있었다 (Tutua et al., 2002). 이와는반대로토양위에잔존해있는식물체잔사에는건물중과질소농도는약 50% 정도가분해되지않고남아있었다 (Tutua et al., 2002; Tagliavini et al., 2007). 본실험에이용된녹비작물은수확후에경운을하지않았기때문에 10~12년생 신고 배나무가필요로하는질소와인산과칼륨 ( 각각 10, 2, 7 kg/10a, Environmental-Friendly Agriculture Research Center, 2010) 은각각 15, 3, 10kg/10a를대략필요로하므로혼파처리가무기성분요구도에가장근접한것으로관찰되었다. 또한 wet + dry deposition에의한추가적인질소공급을고려하면혼파처리는배나무질소요구도를충족시켰던것으로판단되었다. 따라서녹비작물을수확후에경운처리를해주면호밀과헤어리베치단파처리도배나무가흡수하기에적당한질소를토양에환원해주는효과가있을것으로사료된다. 하지만본실험에서관찰된환원가능량을예측한결과는유기농을위하여필요한연구이지만수목에미치는양분시험은장기간의시험및조사로결정되어야하는데 1년의결과로결론을내리는것은한계가있으므로이에따른장기연용의연구가필요할것으로판단된다. 적요본연구는유기재배배과수원시비에있어서화학비료대체를위한녹비작물재배이용기술개발을확립하고자파종방법에따라토양에무기성분환원량과이에따른배나무생장에미치는영향을구명하기위해서수행되었다. 파종방법은전남보성의배과수원독농가에방임초생, 호밀 (16 kg/10 a) 단파, 헤어리베치 (5 kg/10 a) 단파, 호밀 (6.4 kg/10 a) + 헤어리베치 (3 kg/ 10 a) 혼파로나누어서 2007년에 10월에처리하였다. 녹비작물의줄기수는단파처리가혼파처리보다월등히많았다. 처리별건물중은관행방임초생은 362kg/10a로두초종의혼파처리 (856 kg/10 a) 보다낮았다. 전질소환원량은두녹비작물의혼파처리가 13.9 kg/10 a으로관행대비 2.1배높았다. 혼파처리는인산과칼륨환원량을증가시켰고, 10-12년생배나무생장을위해필요로하는질소 (10 kg/10 a), 인산 (2 kg/10 a), 칼륨 (7 kg/10 a) 을충족시켰다. 방임초생재배는가장높은토양용적밀도와가장낮은공극율을나타내었다. 배나무잎은예초후에질소, 인산, 칼륨농도가증가되었고과실품질은처리간에별다른차이가관찰되지않았다.
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