Concentration and Chemical Speciation of K, Na,Ca, Mg and Sr in Sediment from a Upstream of the Pearl River, China

The concentration and chemical speciation of metal elements(K,Na,Ca,Mg and Sr) in sediments were investigated from upstream of the Pearl River,China.The result showed that Total concentrations of metal elements in sediments were in wide range,the ranges of K,Na,Ca,Mg and Sr were 3 016-12 742,135-565,6 794-12 968,2 060-6 229 and 4.01-35.4 mg/kg in sediments.K was dominated by the residual fraction,Sr was dominated by weak acid soluble fraction.The bioavailability of Sr in the area is higher than K.The order of bioavailability was Sr>Na>Ca>Mg>K.

Evaluation and Identification of Resistance to Diseases and Pests for Rice Varieties in Hainan

[Objectives]This study was conducted to select multi-resistant rice varieties in Hainan.[Methods]Seven new rice germplasms were identified by naturally induced disease nursery,field spraying and artificial inoculation.[Results]The restorer line Haihui 1558 was resistant to the dominant races ZB and ZC of rice blast and Tryporyza incertulas,and moderately resistant to pathotype IV of bacterial blight.The restorer line Haihui 227 was resistant to pathotype IV of bacterial blight and T.incertulas.Red rice Hainonghong 1 was resistant to pathotype IV of bacterial blight,and moderately resistant to the dominant races ZB and ZC of rice blast.Black glutinous rice Haifengheinuo 2 was moderately resistant to pathotypes IV of bacterial blight and T.incertulas.[Conclusions]The study provides reference for utilization of rice breeding on resistance to diseases and pests.

Sequence Mutation of Exon 7 of Badh2 Gene and Aroma Identification of Fragrant Rice Varieties

In this study,we performed amplificaion and sequence analysis of exon7 of gene Badh2 of 12 fragrant rice materials,and identified the aroma of fragrant rice materials by the method of seed chewing and KOH soaking,so as to analyze the sequence mutation of exon 7 in the Badh2 gene of rice material and its corresponding relation with the flavor character.The results showed that an 8 bp deletion(aaaa--t---ggc)and a mutation of SNP(g→t)in exon 7 of Badh2 gene were found in 10 materials,including Xiangnuo,Lvjinxiang,Meixiangzhan 2,Huaxiang,Yuexiangxuan 1,Hongyuxiang,Meixiangxuan 1,Baxiangxuan 1,Taixiangxuan 1,Taixiangxuan 2.This mutation was consistent with the mutation of EU155083 sequence in GenBank and was reported for the first time in Chinese rice materials.In these 10 fragrant rice materials with mutation,Huaxiang and Meixiangxuan 1 were identified as the heterozygote genotype,and Hongyuxiang was identified as non-fragrant rice,so the sequence mutation in exon 7 of Badh2 gene in fragrant rice materials did not correspond to aroma traits one by one;and 7 materials were identified as fragrant rice,and the brown rice of Meixiangzhan 2 and Yuexiangyuan 1 had sweet taste.The results could provide a reference for the research on the genetic mechanism of rice aroma character and the promotion of fragrant rice varieties.