| The mankind caused by an irrational diet is dramatic increase in the chronic diseases. The dietary prevention of disease is the key to human health. In 2008, there are approximately 250 million people of diabetes, more than one billion for hyperlipidemia and hypertension as well as overweight people in the world. Ca, Fe and Zn deficiency affect more than 3 billion of the global population. Rice is more than 50% of the staple food, minerals and a source of functional food for the world's population. Evaluation of phenotype and molecule as well as establishment of technology system on Oryza were relatively more, but elemental elements and functional components in brown rice has not been reported so far. Yunnan is the largest center of genetic diversity as well as rich region of functional and nutrition of rice germplasm resources in China. In this study, their zonal characteristics and evolution of ecotype for the content of mineral elements as well as evaluation of functional components in brown rice of the primary core collection in Yunnan rice, corelation between milled or brown rice and soil elements of improved varieties, the phenotypic variation and mineral elements as well as their inter-relationship between the SSR marker of core collection, which has great theoretical significance and high practical value. The results are as following progress:1.There was fist clear zone characteristics of mineral element contents in brown rice of 863 accessions of primary core collection in Yunnan rice, which revealed that systemic relations including indica-japonica subspecies and ecotype differentiation of mineral elements in classification traits. Average P contents in brown rice of 863 accessions of core collection in Yunnan rice are 7.17 times than that of the total phosphorus in soil, and total potassium content of soil are 7.56 times of average K contents in brown rice. The contents (mg·kg-1) of 8 elements in brown rice of 789 accessions core collection for rice landrace from 16 prefectures of five rice regions in Yunnan Province were in turn P(3834.83±486.49) > K(2567.72±336.74) > Mg(2567.72±336.74) > Ca(153.67±55.90) > Zn(33.35±13.65) > Fe(32.08±25.51) > Cu(14.22±11.85) > Mn (13.58±3.22). P content in brown rice was the highest from the northwest Yunnan, the highest Ca, Mg, Fe and Zn concentrations in brown rice from the middle Yunnan, and the highest Cu and Mn contents in brown rice from the southwest Yunnan. The distributing zones with the highest (P, K), middle (Ca, Mg and Mn) and lowest(Fe and Zn) in Yunnan are the enrichment zone of minal resources and most the largest biodiversity. In general, the results show that the mean levels of K, Ca, Mg, Fe and Cu in brown rice for 789 accessions of rice landraces was distinctly lower than that of 94 improved cultivars. They further demonstrate that Ca plays an important role in the differentiation of subspecies indica-japonica, especially to enhance adaptation of cold stress, and that five mineral elements in brown rice enhance the eurytopicity from landrace to improved cultivar. Based on eight mineral elements in brown rice, hierarchical cluster analysis, showed that Yunnan rice could be grouped into rice landrace and improved cultivar, with the rice landrace being further clustered into five subgroups, including group A (purple rice), group B (upland and nuda), group C (glutinous), group D (red rice), group E divided into two subgroup: I (indica, late, white rice, and landrace) and II (japonica, lowland, non-nuda, early–mid, and non-glutinous). 2. The contents of 18 mineral elements in brown rice of improve cultivers in Yunnan rice are clear higher than that of milled rice, 16 elements except P and S are clear lower that of corresponding soils. The correlation of microelements in rice are closer than that of macroelements. The first discovered that 8 elements-related health of human being in brown rice is over 2 times than that of milled rice. The contents of 18 mineral elements in milled and brown rice of 55 accessions elite cultivers as well as corresponding soils, were determined by ICP-AES technique. The analytical results showed that 18 mineral elements (S, Mo, Ba, Ni, Fe, Cr, Na, Al, Cu, P, Sn, Zn, B, Mn, Mg, Ca, Sr and K) are the important active compositions of functional rice,their mean content in milled rice are in turn P > K > S > Mg > Ca > Zn > Na > Al > Mn > Fe > Cu > B > Mo > Ni > Sn > Cr > Ba > Sr, brown rice for P > K > Mg > S > Ca > Zn > Mn > Al > Na > Fe > Cu > B > Mo > Sn > Ni > Cr > Ba > Sr, but soil for Fe > Al > Ca > K > Mg > P > S > Mn > B > Na > Ba > Zn > Cr > Cu > Ni > Sn > Mo > Sr; 16 Mineral elements in milled and brown rice (exception S and P) are clear lower than that of soils. The correlation of 8 microelements (Mo, Ni, Cr, Sr, Mn, Zn, Cu and Na) in milled and brown rice are closer than that of 6 macroelements (P, K, Mg, Ca, S, and Al). There are rich in Fe and Al and Ca in Yunnan soils,but 4 elements (P, K, Mg, and S) give priority to milled and brown rice; The milled rice used for the staple is easier to bring on health problem of human being than that of brown rice.3. The first discovered that there was significantly difference of three functional components in brown rice among different types of primary core collection in Yunnan rice, which showed a clear zone characteristics. The difference of contents and cultivated types of resistant starch andγ-amino butyric acid (GABA) as well as total flavone in brown rice of 996 accessions for primary core collection for Yunnan rice are as follows: Flavonoids contents in brown rice of landraces are the most significantly higher than that of improved cultivars, but GABA content of improved cultivars was significantly higher than that of landraces; resistant starch content of improved cultivars is the most significantly higher than that of landraces. The analytical results showed that the average content (%) for resistant starch in brown rice of 905 accessions from 16 prefectures among five rice regions is 0.75±0.29, it was the most significant highest (p < 0.01) for contents of resistant starch from the middle and South Yunnan province (I, II, III) than that of northern rice regions(V, IV), and the most significant lowest for contents of resistant starch of Lijiang prefecture of northwestern and Zaotong of northeastern in this province than that of 13 prefectures except Diqing prefectures; Indica is significant higher than japonica, glutinous is the most significant higher than non-glutinous, late is the most significant higher than early–mid, red rice and purple rice is the most significant higher than white rice. The average content (mg?kg-1) for GABA in brown rice is 74.3±25.3, and the content of GABA from South Yunnan single/double cropping rice region is clear higher than that of Northwest Yunnan cold highland japonica rice region; It is significant difference of GABA content in brown rice for that Simao prefecture South Yunnan and Yuxi as well as Baoshan prefecture,at least than that of 5 prefectures; Lowland is the most significant higher than that of upland, non-glutinous is the most significant higher than glutinous, late is the most significant higher than early–mid, white rice is the most significant higher than red rice and purple rice. The average content (mg·kg-1) for total flavone in brown rice is 3069.8±1927.5, it was the most significant highest (p < 0.01) for contents of total flavone from South Yunnan (II, III) than that of middle Yunnan; It is the most significant highest from Simao prefecture than that of 8 prefectures, but the most significant lowest from Baoshan prefecture than that of 7 prefectures; Upland is the most significant higher than that of lowland, glutinous is significant higher than non-glutinous, early–mid is most significant higher than late, red rice and purple rice are most significant higher than white rice, and nuda was significant higher than non-nuda. These results revealed that most significant difference between lowland versus upland, glutinous versus nonglutinous, early/mid rice versus, and red/purple versus white rice based on the contents of total flavone and resistant starch as well asγ-amino butyric acid (GABA) in brown rice (p < 0.01), but no significant difference between indica and japonica, awn versus no-awn, common rice and aromatic/soft rice.4. There are some relation between SSR markers and phenotypic traits as well as 8 mineral elements in brown rice of rice landrace in Yunnan Province, which first revealed that mineral elements in brown rice was liable to environmental affect, and grain traits major be controled for genes. It was investigated that allele size of microsatellites associated with phenotypic traits of rice landraces in Yunnan,based on 20 SSR markers and 23 phenotypic traits as well as 8 mineral elements in brown rice within the core collection of 628 accessions; and there was a significant correlation for 182 of 620 pairs among these markers and traits as well as elements. Surprisingly, there was significant correlation for 94 of 180 pairs between allele size of microsatellites and grain traits, and 48 of 160 pairs between allele size of microsatellites and panicle traits. There was a significant correlation between the allele size of 20 SSR markers and some phenotypic traits, such as the significant correlation of 17 pairs between allele size of RM224 and 23 phenotypic traits as well as 8 elements. The allele size of microsatellites was more associated with grain or panicle traits than that of plant traits or element contents in brown rice. Grain length/width ratio and 1―2 internode length, as indica-japonica classification traits, in which two traits were closely associated with the allele size of 14 SSR markers.The 8 elemental concentrations in brown rice among some grades based on number and distance coefficients of alleles for SSR twenty markers for landraces are significantly different (P<0.05), and further understanding the relationship of mineral elements associated with gene diversity. A large variation in elemental concentrations of brown rice, it was ranged from 2160 to 5500 mg P kg-1, from 1130 to 3830 mg K kg-1, from 61.8 to 488 mg Ca kg-1, from 864 to 2020 mg Mg kg-1, from 0.40 to 147 mg Fe kg-1, from 15.1 to 124 mg Zn kg-1, from 0.10 to 59.1 mg Cu kg-1, and from 6.7 to 26.6 mg Mn kg-1. Therefore, genotypic differences of germplasm evaluations for Ca, Fe, and Zn concentrations in rice grain had be detected up to over seven times, which suggesting that selection for high Ca, Fe and Zn cultivars was a effective approach. |
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