2016년 중국으로 우리나라의 6개 RPC에서 쌀 수출을 개시 하면서 얻어진 우리쌀의 품질대비 가격경쟁력의 우수성과 수출 초기에 발생하였던 문제점 등의 해결 사례는 다음과 같다. 중국내 수입하여 유통중인 중단립종의 가격경쟁력은 일본산과 대만산이 우리 수출쌀에 비해서 2~3배 가격이 높게 유통 되고 있어 우리쌀의 품질관리 여부에 따라 수출가능성은 매우 높다고 할 수 있다.
쌀의 백도는 우리나라 수출쌀이 35내외로 낮은 편이나, 중국의 흑룡강성 최고급쌀인 우창쌀의 백도는 40이상으로 높은 편이다. 배아잔존율은 우리나라 수출쌀이 24% 정도이고 중국의 흑룡강성 최고급쌀인 우창쌀은 5%내외이다. 백도는 40이 상으로, 배아잔존율은 하계 3%이하, 동계 5%이하로 가공하였을 때 중국의 소비자 선호도가 증가 할것으로 사료된다.
진공포장이 풀리는 것을 방지하기 위해서는 쌀 사이에 충진재를 넣거나, 포장시 2중접착을 하거나, 열 접착시에 시간을 1~1.5초, 온도를 130~150oC, 진공압력을 270~300 mmHg로 하고, 이동시 편리성을 도모하기 위해 포장지 상부에 손잡이를 만드는 것도 중요하다.
훈증소독은 메틸브로마이드 보다는 인화수소를 이용하는 것과 중국 남방지역으로의 하계 수출시에는 고온 다습한 것을 감안하여 수분함량을 13%내외로 조절하는 것을 추천한다.
In January 2016, Korea began rice exporting to China from six domestic Rice Processing Complexes (RPC). The appearance characteristics and quality of medium-short grain milled rice between the exported Korean rice was compared with Wuchang rice, which is known as high quality in Heilongjiang province in China, and the imported rice from Japan and Taiwan in Chinese circulating marketing. The 1000-grain weight of exported rice is 22.4g, which is similar to that of Chinese Wuchang rice, but it tended to be heavier than that of Japanese and Taiwanese. The rice type is round in exporting Korean, Japanese, and Taiwanese rice while Chinese Wuchang rice is thin and long with 2.5. The head rice rate of export rice was 93.3 ~ 98.4%, which was 95.8% on average, which was higher than that of Chinese Wuchang rice, and similar to that of Japanese, and Taiwanese. The protein content of the export rice was 5.2 ~ 6.2%, which was 5.8% on average, similar to that of Chinese Wuchang rice, Japanese and Taiwanese. Amylose content was 18.5% of the exported rice, which was lower than that of Chinese Wuchang rice and slightly higher than that of Japanese and Taiwanese. The whiteness of the exported Korean rice was 35.6 on the average, lower than 41.8 of Chinese Wuchang rice, and lower than that of Japanese and Taiwanese. The purity of rice variety being exported ranged from 87.5 to 100.0%, which was 96.5% on average. This was much higher than that of Chinese Wuchang rice, while the Japanese and Taiwan rices were similar. The sensory test of rice by the experts, cooked rice of the exported was evaluated to be good for all items such as taste, sticky glutinous, and texture compared to Chinese Wuchang rice.
This study was conducted to develop the early maturing rice lines with genes conferring resistance to bacterial blight and rice stripe virus to enhance the adaptability in plain area. Unkwang carrying Xa3 was used as a recurrent parent and SR30075 carrying Xa4+xa5+Xa21+Stvb-i was used as a donor parent. RL1(Resistant Line, BC1F7), RL2, RL3, RL4, and RL5(BC2F6) were bred through bio-assay of K3a race inoculation and phenotypic selection of agronomic traits. The presence of introduced genes was confirmed by testing the resistance levels against bacterial blight and rice stripe virus and then double-checked by using DNA marker. RL1 has all target genes, Xa3+xa5+Xa21+Stvb-i. RL2, RL3, and RL5 have Xa3+Xa21+Stvb-i whereas RL4 has only Xa21. Rice lines carrying Stvb-i showed resistance reaction to rice stripe virus. The combinations of bacterial blight resistant genes(Xa3+xa5+Xa21 and Xa3+Xa21) were found to be promising, as the rice lines carrying these genes enhanced a strong resistant reaction against 16 bacterial blight isolates. Also, the inoculation of K3a race did not alter the brown rice yield, ripened grain ratio and kernel quality of brown rice compared to control. Although RL1 containing all the target resistance genes showed excellent resistance performance, it is not suitable to cultivate in plain area due to instability to lodging, 80% yield level than Unkwang, and low grain quality. RL5 backcrossed twice with Unkwang was found to be a promising line due to its effective resistance gene combination, Xa3+Xa21+Stvb-i and good agronomic traits such as stability to lodging, higher yield and quality compared to Unkwang.
Rice grain number and grain dimensions including grain length-width ratio are critical components in determining the rice yield and quality. Manual or visual inspection for breeding lines and germplasm over these traits are time-consuming jobs. We developed and tested two algorithms for analysing grain number and dimensions (grain length, grain width) through image analysis system, Metamorph offline 7.0 (Molecular devices™). The algorithm for determining number of grain and shape constitutes a series of fragmentation processes including Shading, Color separate, Threshold, Euclidean, Dialate, Watershed Line, Arithmetic. When the six rice cultivars with different grain shapes were tested, there was no difference in the averaged values and distribution for the grain number and grain length between mannual and image analysis methods. However, image analysis resulted in the slightly increased values for grain width and more wider distribution whereas length/width ratio was slightly reduced by about 0.1, indicating that image analysis can be utilized more effectively and accuately in investigating the grain number and dimensions for sizable breeding lines.
Breeding the whole crop siliage rice cultivar basically requires priority in high biomass and grain yield and tolerance biotic and abiotic stresses. In this context, AA genome wild rices are potential resources to broaden genetic variability for whole crop silage cultivar. We have developed several introgression populations from crosses with three AA genome wild rices, O.glaberrima, O.rufipogon, and O.longistamina. Among these populations, the three BC4F8 near isogenic lines (NILs) derived from a cross of Milyang 23 and O.glaberrima(acc. 101154) could produce the high-yielding lines surpassing Milyang 23 by 20% in grain yield. Introgression lines from crosses with 4 accessions of O.rufipogon with japonica rices, Hwaseongbyeo and Ilpumbyeo had huge agronomic variability and very tall and vigorous lines possessing culm length of 125 ∼ 187cm were selected as promising potential parents to improve biomass of existing cultivars. These selections with high yield potential and biomass will be crossed to create another gene pool to combine high yield and biomass and anther culture breeding could be useful to develop genetically fixed F2 lines with both traits.
The Brown planthopper (BPH) is one of the most serious pests of rice affecting rice yield and quality throughout the country. AA genome wild rice, O.rufipogon is a useful source of insect resistance to BPH. To broaden the BPH resistance in the existing quality japonica cultivars, crossess were made between a highly susceptible quality rice cultivar, Ilpumbyeo, and five accessions (acc.106109, 106286, 106424,105908,80671) of O.rufipogon. Among 126 F8 RIL lines evaluated for Bph resistance at NICS, the highly resistant 22 introgression lines were identified and Ilpumbyeo*2/O.rufipogon (acc.105908) showed different genotype at the marker loci of Bph1, Bph18 and the resistance reaction to BPH in the BC1F2 population fitted to 3:1 segregation mode, indicating the possible new dominant resistance gene might be involved. Polymorphism between Ilpumbyeo and resistant line was low with 36 (27%) SSR markers among 130 markers detected. Currently mapping population of BC2F2 is established and SSR marker analysis will be carried out to find out the resistance loci.
To develop the STS (Sequence Tagged Site) marker for discrimination between oat cultivars used the EEG (Euchromatin Enriched Genomic) DNA library in oat. The EEG DNA library was constructed the Mcr A and Mcr BC system in DH5 alpha bacterial cell line. About 3,500 EEG colonies had been constructed by using junk DNA exclusion. About 800 colonies were selected that included insert DNA more than 500 bp. It was analyzed the genetic information by using blast searches of NCBI web site. More than three hundred STS primer sets were developed using sequencing data of selected colonies and about 90 primer sets which showed single band were selected in Olgwiri. It was applied to twelve oat cultivars including Olgwiri and has been shown polymorphism at 15%. PCR product which amplified with selected STS primer was treated with six endonucleases and was showed polymorphic bands. These primers could be useful for specific allele tagging in mapping populations and germplasm and for the study of functional genomics of oat.