벼 이앙기별 인산에 의한 논조류 발생과 제초제에 의한 방제 효과는 다음과 같다.
1. 단작 및 이모작 벼 재배지에서 총출현 종수는 61종으로 녹조류 34종, 규조류 16종, 유글레나 7종, 그리고 남조류 4종이 발생하였고, 녹조류, 규조류는 이모작지가 많았고, 유글레나는 같았으며 남조류는 단작이 많았다.
2. 인산을 이앙전에 50%처리하고 분얼기에 50% 시비하였을 때 총인이 0.06 mg L-1로 가장 높았고, 조류 발생량도 무인산 대비 6월 6일 이앙한 구에서 14.8 mg 20 ml-1으로 3배 이상, 6월 20일에 이앙한 구에서 9.8 mg 20 ml-1 2배 이상 증가하였다.
3. 벼 생육단계별 분얼기, 유수형성기, 그리고 수잉기의 토양 인산의 함량은 관행 및 인산분시별로 유수형성기가 인산의 함량이 116.5~191.8 mg kg-1으로 가장 높은 경향이었으며 무 처리구에서는 15.5~29.1 mg kg-1로 낮았다. 이앙시기별로는 이앙이 빠를수록 높은 경향이었으며, 인산분시별로는 관행에 비해 분시하였을 때 높은 경향을 보였다.
4. 클로로필-a 함량은 6월 6일 이앙한 구에서는 제초제 처리 후 7일에 가장 낮은 6.3 mg m-3 이고, 7월 상순에 무처리구에서 75.8 mg m-3 로 가장 높았다. 6월 20일 이앙한 구에서는 제초제 처리후 7일에 가장 높은 경향이었으며 제초제 처리 후 14일과 21일은 감소하는 경향이었다
5. 논조류 억제율은 quinoclamine이 단작에서 59.2%, 이모 작에는 44.4%로 가장 높았으며, 다음으로 bromobutide + imazosulfuron + pyraclonil > benzobicyclon + mefenacet + peno xsulam >무처리 순이었다.
To select the forage millet variety suitable for cultivation in the reclaimed tideland, forage and feed value compared for 16 millet cultivars grown at the Saemangyem reclaimed tideland, Korea, from April to August in 2014-2015. In order to select barnyard millet for forage that substitute rice, a total of 16 germplasm were collected, including germplasm in retained by the Rudal Development Administration’s Agricultural Genetic Resources Center, and domestic and foreign germplasm which other researches were retaining in Korea. Out of the 16 germplasm, including Jeju barnyard grass (JBG), were initially selected which are late-heading, long plant height, wide leaves, seed shatter-resistant, and with high dry forage yield in Saemangyem reclaimed tideland. The highest fresh weight and dry weight of barnyard millet were 78.4 ton ha-1, and 21.1ton ha-1 in transplanting May 10. The content of proline was the highest in JBG and IT153610 variety. Total phenol contents were the highest in JBG and the lowest in PI183332 variety, but very high in yield ability were selected; JBG was selected.
To determine the effect of soil salinity and crop response according to drainage methods, a field experiment was conducted in reclaimed tidal flat land adjacent to Yeongsangang located at Sanyimyon Haenamgun Jeonnam province for three years from 2012 to 2014. Three drainage methods, subsurface drainage (SD), 30 cm open ditch drainage (OD30) and 60cm open ditch drainage (OD60) tested on silt loam soil. In SD and ND, soil salinity were lower than OD30 and OD60 but there was no significant soil EC to the depth of open ditch. SD had a little effect in lowering ground water table. Waterlogging intensity in SEW30 values during the growing season was the lowest in SD 297 compared with the OD30 855, ND 1,420 and OD60 1,553 cm-day. From the above results, subsurface drainage system control soil salinity and waterlogging. Also, the open ditch drainage had an effect on drainage improvement but there was no significant effect on desalinization. So drainage and soil reclamation were essentially needed to stable upland crop cultivation at the reclaimed tidal flat land.
현재까지 우리나라 벼 재배에서 sulfonylurea계 제초제들에대한 저항성 잡초로 보고된 잡초들은 간척지 벼 재배지에서물옥잠이 처음으로 확인된 다음 일년생 잡초 10초종, 다년생잡초 4초종이 발생하여 모두 14종이다. 그리고 2009년Acetolactate Synthase 및 Acetyl-CoA Carboxylase 억제제들에 대한 강피가 저항성으로 처음 보고되었다. 저항성 잡초 발생 초창기에는 sulfonylurea계 제초제들에 대한 저항성초종들인 광엽 및 방동사니과 잡초들 중에서 하나의 저항성 잡초 초종이 논에 주로 우점하였으나 현재에는 한 논에 여러 가지 잡초 초종들이 함께 복합적으로 우점하고 있다. 저항성 잡초 생체중 50%를 억제하는 약제 농도(GR50)는 저항성 잡초가 감수성 잡초 보다 훨씬 높았다. Acetyl-CoA Carboxylase 및 AcetolactateSynthase 억제제들에 대한 저항성 강피도 GR50은 감수성 강피 보다 훨씬 높게 나타났다. 우리나라 벼 재배지에서제초제 저항성 잡초들의 우점 원인은 잡초 생태적 및 제초제작용기작 측면으로 구분할 수 있다. 잡초 생태적 측면에서는종자생산량과 생육이 빠른 잡초들이 저항성으로 변이한다. 제초제 작용기작 측면에서 저항성잡초 발생의 주원인은 약효가길고 선택성이 매우 좋은 sulfonylurea계 제초제들의 높은 선호 때문이다. 국내 논에서 sulfonylurea계 제초제들의 사용 비율은 약 96%이다. 벼 직파재배지에서 Acetolactate Synthase 및Acetyl-CoA Carboxylase 억제제들의 계속적 사용은 저항성강피 발생을 가능하게 하였다. Sulfonylurea계 제초제들에 대한 저항성 물옥잠의 acetolactate synthase 활성을 50% 억제하는 제초제 농도인 I50은 감수성 물옥잠에 비해 훨씬 높았는데이것은 흡수 및 이행에 의한 차이보다는 Acetolactate Synthasegene의 돌연변이(mutation) 때문인 것으로 나타났다. 즉Acetolactate Synthase gene amino acid 197번째 proline이serine로 치환되었기 때문이다. 저항성 잡초 관리를 위하여 벤조비싸이크론(benzobicyclon) 등은 물달개비 및 올챙이고랭이를 함께 관리하는 것이 가능하다. 또한 Acetolactate Synthase및 Acetyl-CoA Carboxylase 억제제들에 대한 저항성 강피의관리는 메페나세트(mefenacet) 등이 2.5엽기까지 가능하다. 그리고 우리나라 벼 재배지에서 제초제 저항성잡초들을 방제하는데 적지 않은 난관들이 있다. 첫째, 지금까지 저항성 발생제초제들인 Acetolactate Synthase 및 Acetyl-CoA Carboxylase억제제들의 판매량이 늘고 있기 때문에 저항성 잡초들은 꾸준히 발생하고 번질 것이다. 둘째, 미국 등의 선진국들과 같은연구인력 및 기관이 많이 부족하다.
This study was carried out to identify the optimum seeding dates for selecting a double-cropping system and to assess the effect of polyethylene film mulching on the yield of Proso millet. Seeds of the varieties Hwanggeumgijang and Ibaegchal were sown in Miryang on five different dates: 1st (May 25), 2nd (June 15), 3rd (June 25), 4th (July 5), and 5th (July 15), with and without polyvinyl mulching. The varieties have different characteristics, for example, Hwanggeumgijang is an early-maturing type and more sensitive to temperature, whereas Ibaegchal is a medium-maturing type and more sensitive to the duration for which it is exposed to sunlight. Late-sown Hwanggeumgijang had a short heading date from seeding and required a low accumulated temperature. It also had a shorter period of heading, a shorter culm length and a shorter diameter of stem. In contrast, it had had a higher number of ears per m2 although similar ear length and similar 1000-grain weight. The yield potential of Hwanggeumgijang was found to decrease at a late seeding date. In particular, it significantly decreased at the seeding date of July 15. In the case of cultivation with polyvinyl mulching, the period of heading was shorter by 2–4 days and the yield potential was increased by approximately 12–32%. The length and diameter of culm in Ibaegchal were slowly decreased, but the length of ear, the 1000-grain weight and the yield potential were similar for all seeding dates (except July 15) and cultivation with and without mulching. When sown late, the length and diameter of the culm of Ibaegchal very rapidly decreased by the July 15 seeding date. The protein content of Ibaegchal was higher but the amlyose content of Ibaechal was lower compared to Hwanggeumgijang. At late seeding dates, the protein contents of the two varieties increased but the amylose contents were similar.
Wheat is one of the most important food crops in the world and provides 20% of nutritional requirement to the consumers in developing countries. The consumption per capita of wheat is persistent but the self-sufficiency has decreased owing to the less competitive world market and double cropping system with rice in Korea. This study was conducted to obtain baseline data on the selection lines with early maturity and good agronomic traits. Geumgangmil, a leading Korean variety, was crossed with CIMMYT’s line, and a DH (double haploid) line was released using pollens of Maize in Mexico. The 71 inbred lines were grown in fields at NICS, Miryang. The culm length of inbred lines were normally distributed from 37cm to 106cm, though that of the P1 (Geumgangmil) was 71 and P2 (CIMMYT’s Line) was 77cm. Especially, some lines were very short and measured below 50cm. The spike lengths of most of the lines were longer than that of P1 (7.5cm), but were normally distributed. The number of spikelet was less than that in P2 (19ea.), but was more than P1(10ea.). The heading day of most of the lines was between P1 (11th April) and P2 (25th April) and the maturity day of the lines was similar to P1 (1st June) but 5 lines showed 2~6 days shorter maturity period than that of P1. However, 20 lines were found to have 2~10 days longer maturity period than that of P2.