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Japonica rice variety Kanto 194 as the donor of resistance gene Stv-bi and low-amylose content gene Wx-mq was used to improve the resistance and eating quality of Wuyujing 3 by the breeding strategy of backcross. In continuous backcross and selfcross generations, the related molecular markers with Stv-bi and Wx-mq genes were utilized for genotypic detection by associated with resistance identification of rice stripe disease and agronomic traits selection. Finally, 10 improved lines with homozygous genotype Stv-biStv-biWx-mqWx-mq were obtained from BC3F4 generation. The results of comparative analysis indicated that most characters of these lines were consistent with those of recipient parent Wuyujing 3, except for the improved resistance, appearance and eating quality. By evaluation of the comprehensive performance of them, two excellent lines K01 and K04 were selected for further experiments.

GW2 is an important gene that regulates grain width and weight. We used cDNA clone to obtain the sequences of GW2 from large- and small-grained rice varieties, TD70 and Kasalath, respectively. Then, we developed a dCAPS (derived cleaved amplified polymorphic sequence) marker on the basis of the sequence difference between functional and nonfunctional GW2 genes to analyze the genotypes and phenotypes of recombinant inbred lines. Results showed that the sequence of GW2TD70 had a single nucleotide deletion at site 316 that generates a termination codon. This codon terminated the GW2 protein in advance. By contrast, the sequence of GW2Kasalath encoded an intact protein. A novel dCAPS marker was designed in accordance with a base A deletion at site 316 of the sequence. After the PCR product was digested by ApoI, TD70 showed 21 and 30 bp fragments, and Kasalath showed a 51 bp fragment. Up to 82 lines contained GW2TD70, and 158 lines contained GW2Kasalath. The lines that contained TD70 alleles displayed substantial increases in width and 1000-grain weight. This result suggested that GW2 played a critical role in rice breeding.

Abstract Background Methyl jasmonate (MeJA) has been successfully used as an effective elicitor to enhance production of taxol and other taxanes in cultured Taxus cells. However the mechanism of MeJA-mediated taxane biosynthesis remains unclear. Genomic information for species in the genus Taxus is currently unavailable. Therefore, information about the transcriptome of Taxus cells and specifically, description of changes in gene expression in response to MeJA, is needed for the better exploration of the biological mechanisms of MeJA-mediated taxane biosynthesis. Results In this research, the transcriptome profiles of T. chinensis cells at 16 hours (T16) after MeJA treatment and of mock-treated cells (T0) were analyzed by “RNA-seq” to investigate the transcriptional alterations of Taxus cell in response to MeJA elicitation. More than 58 million reads (200 bp in length) of cDNA from both samples were generated, and 46,581 unigenes were found. There were 13,469 genes found to be expressed differentially between the two timepoints, including all of the known jasmonate (JA) biosynthesis/JA signaling pathway genes and taxol-related genes. The qRT-PCR results showed that the expression profiles of 12 randomly selected DEGs and 10 taxol biosynthesis genes were found to be consistent with the RNA-Seq data. MeJA appeared to stimulate a large number of genes involved in several relevant functional categories, such as plant hormone biosynthesis and phenylpropanoid biosynthesis. Additionally, many genes encoding transcription factors were shown to respond to MeJA elicitation. Conclusions The results of a transcriptome analysis suggest that exogenous application of MeJA could induce JA biosynthesis/JA signaling pathway/defence responses, activate a series of transcription factors, as well as increase expression of genes in the terpenoid biosynthesis pathway responsible for taxol synthesis. This comprehensive description of gene expression information could greatly facilitate our understanding of the molecular mechanisms of MeJA-mediated taxane biosynthesis in Taxus cells.

According to geographic origin and amylose content, 87 investigated japonica rice cultivars were divided into three types: Jiangsu common japonica rice, Northeast japonica rice and Jiangsu semi-waxy japonica rice. In order to explore the eating quality characteristics of the three types of japonica rice and their molecular basis, the physicochemical properties and the sequence of major genes Wx and OsSSIIa for starch synthesis were analyzed. Compared with Northeast japonica rice, Jiangsu common japonica rice had lower amylose content, higher protein content and gelatinization temperature, and similar gel consistency and RVA profiles. Compared with Northeast japonica rice and Jiangsu common japonica rice, Jiangsu semi-waxy japonica rice contained the lowest amylose content, the highest gel consistency and unique RVA profile. Variation coefficients of all characters except for setback value were small in three types of rice varieties, indicating that there was a great range of retrogradation within all the cultivars. The correlation coefficients among traits were different among three types of japonica rice, which indicated that the correlations were affected by the ecological conditions of different regions and properties of varieties. By cluster analysis, 87 japonica rice varieties (lines) were divided into four groups. Jiangsu common and Northeast japonica rice varieties (lines) were intersected in group I and group II. Group III was composed of two lines of Jiangsu common japonica rice and one semi-waxy variety (Xudao 9), and the most of their character values were ranged between those common japonica rice and semi-waxy japonica rice. The Jiangsu semi-waxy rice varieties (lines) with unique physicochemical characteristics were clustered into group IV. By sequence analysis, there was no difference in Wxb gene between Jiangsu common japonica rice and Northeast japonica rice, but in Jiangsu semi-waxy japonica rice G/A substitution occurred in Exon 4 of Wxb, which is the Wxmp allele. The higher gelatinization temperature in some of Jiangsu japonica rice varieties (lines) was controlled by the allele of OsSSIIa (G-GC). [ABSTRACT FROM AUTHOR]

Proanthocyanidins (PCs) with poor bioavailability were argued for their health benefits. In this study, water-soluble polymeric polyphenolic PCs fractions from Pyracantha fortuneana fruit were used to investigate whether the presence of PCs is correlated with the increased cell antioxidant activities (CAA) of quercetin (Q). The results indicated that the most decrement in the values of EC 50 , which Q inhibited peroxyl radical-induced DCFH oxidation effective in the HepG 2 cells, was observed to be 2.91 (vs. control 5.97) in the present of the fraction with 15.8 of the average degree of polymerisation of PCs (ADP). Also, the order of efficacy was the same with the ADP of PCs. Further, this effect is associated with the improvement of the solubility and stability of Q after the addition of the PCs. Our current study suggests that the additive effects of PCs on small molecular polyphenols may be responsible for their antioxidant benefits in vivo . [ABSTRACT FROM AUTHOR]

Nitrogen (N) deficiency is a major yield-limiting factor in rice production. The objective of this study was to identify putative QTLs for low-N stress tolerance of rice, using an advanced backcross population derived from crosses between an indica cultivar '93-11' and a japonica cultivar 'Nipponbare' and genotyped at 250 marker loci. Plant height, maximum root length, root dry weight, shoot dry weight and plant dry weight under two N conditions and their relative traits were used to evaluate low-N tolerance at the seedling stage. A total of 44 QTLs were identified on chromosomes 1, 2, 3, 4, 5, 6, 8 and 9. Eight intervals on five chromosomes were identified to harbour multiple QTLs, suggesting pleiotropism or multigenic effects according to the contributor of alleles. Some QTL clusters were found in the nearby regions of genes associated with N recycling in rice, indicating that the key N metabolism genes might have effects on the expression of QTLs. Several unique QTLs for relative traits were detected, which suggested the specific genetic basis of relative performance. [ABSTRACT FROM AUTHOR]

Highlights: [•] Lycopene accounted for approximately 96% of the total carotenoids. [•] Cis-lycopene accounted for approximately 35% of the total lycopene. [•] The content and nutritional quality of lycopene from B. trispora were high. [•] B. trispora is an ideal source of natural lycopene. [•] 2-isopropylimidazole can be completely biodegraded. [Copyright &y& Elsevier]

Two new dammarane-type compounds were isolated from the leaves and stems of Panax quinquefolium L. The new compounds were named as pseudo-ginsenoside RT6 (1) and pseudoginsengenin R1 (2). The structures of the new compounds were elucidated by the combined analysis of NMR and HR-ESI-MS as (20S,24R)-6-O-β-d-glucopyranosyl-dammar-3-one-20,24-epoxy-6α,12β,25-triol (1) and (20S,24R)-dammar-3-one-20,24-epoxy-6α,12β,25-triol (2). [ABSTRACT FROM AUTHOR]