본 연구는 allelopathic potential을 지닌 벼의 교잡종을 포장에서 재배하여 그 식물체의 잎을 생물검정에 이용하여 allelopathy 효과 유무를 검정하고, 생물검정으로 선발된 교잡종을 대상으로 phenolic compounds를 조사하여 allelochemical로써의 가능성을 확인하고 나아가 phenolic compounds 생합성에 관여하는 효소의 활성 측정과 이 효소의 작용에 의해 유도되는 phenolic compounds를 구명한 결과는 다음과 같다. 1. 포장상태에서 피를 대상으로 생물검정을 실시한 결과 양친으로는 Kouketsumochi, Woo co chin yu에서 공통적으로 90% 이상의 높은 피뿌리 생장 억제율을 보였고, 교잡종에서는 Kouketsumochi/Woo co chin yu, Dongjinbyeo/Kouketsumochi, Dongjinbyeo/Woo co chin yu 조합에서 80% 이상의 높은 억제율을 나타냈다. 2. Kouketsumochi의 PAL 활성은 protein 1kg당 로 타 공시품종보다 높았다. 또한 Kouketsumochi와의 교잡종도 타교잡종보다 높은 것으로 나타났다. 3. Kouketsumochi의 cinnamate 함량은 생체중 1g당 으로서 다른품종이나 교잡종보다 2~5배 높았고, Kouketsumochi와의 교잡종도 타교잡종보다 높았다.
벼멸구에 대한 벼품종의 저항성요인으로 주목되고 있는 선호성, 란 및 약충기간, 부화 및 우화률, 성비, 성충의 수명 및 산란력 등을 조사하였다. 식이 및 산란선호성은 동률벼에서 생태형 모두 높은 선호성을 보였으며, 청청벼와 밀양63호에서는 각각 생태형-2와 3에서 약간 높은 선호성을 보였으나, 동률벼에 비해서는 현저히 낮은 선호성이었다. 난 및 약충기간과 부화율, 우화률 및 생장 지수는 생태형-1의 경 우 타 품종에 比해 密陽 23號에 서 짧고, 높았으며 , 또態型-2와 3 은 各各 좁 팍벼 와 密陽 63號에 서 密陽 23號에서와 같이 짧고, 높게 나타났다. 성충의 수명과 산란수도 생태형-1의 경우 타 품종에 비해 밀양 23호에서 길고, 많았으며, 생태형-2와 3은 각각 청청벼와 밀양 6 63호에서 밀양 23호에서와 같이 수명이 길고 산란수도 많았다.
시험은 흰빛잎마름병의 품종별 감수성과 수량 및 품질에 미치는 영향을 구명코자 시비량을 보비재배와 다비재배로 구분하여 전남지역에서 수행 되었다. 흰빛잎마름병은 발생은 다비조건에서 심했으며 심한 발병은 수도 품종들의 등숙에 영향을 주어 수량 감수를 초래하였고 청미율은 품질을 저하 시켰다. 또한 조생계품종에서는 지엽과 차엽이 발병되었지만 중, 만생계품종에서는 지, 차, 삼엽이 발병되었다. 이러한 차이는 보비조건에서 보다 다비조건에서 더욱 뚜렷하였다. 이 병에 대한 저항성품종은 태백벼, 백운찰벼, 팔공벼, 밀양 42호이었고 밀양 30호, 금강벼, 낙동벼, 진주벼는 감수성이었으며 이러한 경향은 시비 수준간에 같은 경향이었다.
도열병의 특이적저항성에 관여하는 항균성물질인 phytoalexin을 친화적조합 혹은 비친화적조합에서 광범위하게 조사하였고 더 나아가 이의 경시적인 생성량과 생성속도 그리고 질소과용에 의한 생성량의 변화를 조사한 결과는 다음과 같다. 1. 공시수도품종 진흥, 수원 288호, 밀양 23호, Fukei 95, Chikeung, 노풍, 유신, 이리 344호, 9품종과 공시도열병균 race , 및 N-2 3균계의 비친화적조합에서는 친화적조합에서 보다 훨씬 높은 phytoalexin 활성을 나타냈으며 친화적조합에서도 이의 활성이 인정되었다. 2. 균부화액 접종후 phytoalexin 활성의 경시적변화에서는 접종 24시간후에 명백히 그 활성이 인정되었으며 36시간후에는 최고활성을 보였는데 그 이후로 점차 감소하였다. 그러나 진흥과 N-2와의 조합에서는 24시간에 peak에 달하였고 그 이후 감소하였다. 친화적조합과 비친화적조합을 비교해 보면 친화적조합에서 보다 비친화적조합에서 활성이 높았고 증가속도도 약간 빨랐다. 3. 질소시여수준에 따른 phytoalexin 활성의 변화는 전반적으로 친화적조합에서나 비친화적조합에서나 과시비에 의해 그 활성이 떨어졌으며 비친화적조합에서 더욱 심하였다. 4. 생엽착즙액에서 포자발아율은 친화적조합 또는 비친화적조합 모두 일정한 경향을 볼 수 없었으며 조합간의 유의적인 차이도 인정되지 않았다.
To identify rice (Oryza sativa L.) cultivars suitable for Italian ryegrass (Lolium multiflorum Lam.)–rice double cropping systems, we investigated the yield and grain quality of four different midseason maturing rice cultivars (‘Daebo’, ‘Haepum’, ‘Haiami’, and ‘Samdeog’) and four midseason-to-late maturing rice cultivars (‘Hyunpoom’, ‘Saeilmi’, ‘Saenuri’, and ‘Samkwang’) in single rice cropping and Italian ryegrass–rice double cropping systems in paddy fields of Miryang, South Korea. We found that organic matter and available P2O5 content slightly decreased, whereas Na content increased, in the soil where Italian ryegrass was cultivated during winter compared to that in the soil that remained fallow during winter. The pH, electrical conductivity, organic matter, and contents of K+, Ca2+, Mg2+, and Na+ decreased, whereas the available P2O5 content slightly increased, in the soil where rice was harvested in both single and double cropping systems. However, compared to the optimum soil conditions for rice cultivation, available P2O5 and K+ content were high and Mg2+ content was low in both single and double cropping systems. At the heading stage, the culm length and leaf color slightly increased in most of the rice cultivars, whereas the panicle length and number slightly decreased, in the double cropped system. After harvesting, spikelet number and milled rice yield did not show a significant difference between single and double cropping systems. However, the ripened grain rate and weight per thousand grains increased slightly in the ‘Saeilmi’ and ‘Samkwang’ cultivars but remained either stable or slightly low in other cultivars in the double cropping system. The milled rice yield was high (> 500 kg/10a) in ‘Daebo’ and ‘Haepum’ among midseason maturing rice cultivars, and in ‘Saeilmi’ and ‘Saenuri’ among midseason-to-late maturing rice cultivars, in both single and double cropping systems. The head rice rate was high in midseason maturing rice cultivars in the double cropping systems, reaching > 70% in ‘Haepum’ and ‘Haiami’ cultivars, whereas it decreased in most midseason-to-late maturing rice cultivars (excluding ‘Samkwang’ cultivar), in double cropping systems. Particularly, it exceeded > 70% in the ‘Saenuri’ cultivar in both single and double cropping systems. The protein content in milled rice increased, whereas the amylose content either remained stable or slightly increased, in double cropping systems. The Toyo taste value decreased in all midseason-to-late maturing rice cultivars and slightly increased in the ‘Daebo’ and ‘Haiami’ cultivars among midseason maturing rice cultivars in double cropping systems. However, Toyo taste values in the ‘Haepum’, ‘Haiami’, and ‘Saenuri’ cultivars exceeding > 80% in both single and double cropping systems. Therefore, we recommend ‘Haepum’, ‘Haiami’, and ‘Saenuri’ cultivars as candidates for Italian ryegrass–rice double cropping systems due to high yield, head rice rate, and Toyo taste value.
The purpose of this study was to provide basic data on the genetic and environmental effects of stickiness in glutinous rice varieties. In our study, we analyzed the genotype-by-environment (G × E) interactions of the stickiness using six glutinous rice varieties under six environmental conditions. AMMI (Additive Main Effects and Multiplicative Interaction) analysis results showed that genotype (variety, G), environment (cultivation region, E) and G × E interaction were highly significant (P < 0.001). Among all the variations of stickiness for glutinous rice varieties, the environmental effect was 24.5%, the genetic effect was 37.1%, and the G × E interaction effect was 28.9%. From the AMMI analysis, the IPCA1 scores of Aranghangchal (G6, IPCA1: 3.85) and Hwaseonchal (G4, IPCA1: -5.24) was lower than other varieties. On the other hand, the Sangjuchal (G1, IPCA1: -61.23) and Boseogchal (G2, IPCA1: 41.21) were highly affected by environmental effects. In this study, there were large differences in stickiness according to region of cultivation. In the future, it is considered that a precise study should be carried out on the environmental factors that may increase the stickiness of glutinous rice varieties.
Rice quality should be considered as a primary consumer requirement. Regarding marketing, characteristics such as appearance, physicochemical properties, and palatability of brand rice are of high economic importance. Therefore, this study was conducted to select the optimal rice cultivars representing the commercial rice brands of Gyeongsangbuk-do province in Korea. Various rice grain quality components, grain appearance, several physicochemical properties of rice grain, and texture or palatability of cooked rice grains of ten cultivars (namely ‘top quality rice’) cultivated at three different locations, such as inland mountainous and southern plain areas of Gyeongsangbuk-do province in 2013~2014, were evaluated, and the obtained data was analyzed. ‘Hiami’ showed slightly higher protein contents and lower palatability of cooked rice than the other rice cultivars. Rice production and head rice yield produced at Gumi were the highest. The protein content of milled rice produced at Andong, an inland mountainous region, was approximately 0.3% point lower than that from other locations, whereas the amylose content of milled rice was approximately 1% point higher than those from the other plain regions, Daegu and Gumi. We evaluated the texture, Glossiness value determined using a Toyo teste meter and palatability of cooked rice of ten cultivars. The hardness of cooked rice produced in Andong was slightly lower than that produced in Daegu and Gumi, and additionally, the palatability of cooked rice produced in Andong was the best, followed by that producted in Gumi and Daegu. Considering rice yield and grain quality in the major rice cultivation areas of Gyeongsangbuk-do province, the rice cultivars that may be suitable for each region could be recommended mid-late maturation: ‘Younghojinmi’ and ‘Mipum’ in Daegu, ‘Daebo’, ‘Samgwang’, Chilbo’ and ‘Younghojinmi’ in Gumi, ‘Samgwang’, ‘Jinsumi’ and ‘Sukwang’ in Andong. These results obtained in this study imply that the selected cultivars with high yield and quality could be recommended with high priority to rice farmers in the regions.
Rice flours from five rice (Oryza sativa L.) varieties with different amylose content were prepared by both wet and dry milling processes. The moisture content of wet-milled rice flours (WMR) was approximately three-times higher than that of dry-milled rice flours (DMR). Water absorption index (WAI), water solubility index (WSI), and swelling power (SP) increased in proportion to temperature. The WAI, WSI and SP values of DMR were higher than those of WMR. Baeokchal (BOC), which is a waxy rice cultivar, had a significantly high WSI value. Pasting properties of DMR, except for the BOC cultivar, resulted in an increase in peak, trough, final, and setback viscosities. The levels of resistant starch in four cultivars, except for Dodamssal (DDS), were under 1%, irrespective of the milling process, whereas the resistant starch contents of DMR and WMR in DDS were 9.18% and 6.27%, respectively. In vitro digestibility of WMR was higher than that of DMR, and the estimated glycemic index of the rice flour varieties ranged from 57.6 to 81.3. Damaged starch content of WMR was less than that of DMR; in addition, a negative correlation was observed between the amylose and damaged starch contents of WMR. These results suggest that the properties of rice flour vary depending on the milling method and flour variety, and could be a reference for selecting the appropriate processing method.
The purpose of this study was to evaluate the effects of rice cultivars (Hangaru, Seolgaeng, Dasan-1 and Anda) on the quality characteristics of rice beer. Hangaru and Seolgaeng which are soft rice varieties, had moisture contents that were 14.48% and 14.62% higher than those of Dasan-1 and Anda, respectively. Dasan-1 and Anda showed higher protein contents than those of the other two varieties. The amylose content of Hangaru was found to be 17.71% lower than that of the other varieties, whereas the reducing sugar content of Hangaru and Seolgaeng was higher than that of Dasan-1 and Anda. Hardness measurements for Hangaru and Seolgaeng were lower than those for Dasan-1 and Anda. Measurements of the alcohol content, pH and color of beers brewed using these rice cultivars revealed no significant difference among the cultivars. However, measurement results for bitterness showed that beers brewed with Hangaru and Seolgaeng had lower bitterness than did the beers brewed with Dasan-1 and Anda. The results of this study indicate that Hangaru and Seolgaeng can be considered as cultivars with brewing qualities suitable for rice beer.